WO2024187294A1 - 隔离膜、电池和用电装置 - Google Patents

隔离膜、电池和用电装置 Download PDF

Info

Publication number
WO2024187294A1
WO2024187294A1 PCT/CN2023/080663 CN2023080663W WO2024187294A1 WO 2024187294 A1 WO2024187294 A1 WO 2024187294A1 CN 2023080663 W CN2023080663 W CN 2023080663W WO 2024187294 A1 WO2024187294 A1 WO 2024187294A1
Authority
WO
WIPO (PCT)
Prior art keywords
lithium
coating
particles
optionally
battery
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2023/080663
Other languages
English (en)
French (fr)
Inventor
令月霞
范玉磊
刘锋
关文浩
钟韡
葛销明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Contemporary Amperex Technology Co Ltd
Original Assignee
Contemporary Amperex Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Contemporary Amperex Technology Co Ltd filed Critical Contemporary Amperex Technology Co Ltd
Priority to PCT/CN2023/080663 priority Critical patent/WO2024187294A1/zh
Priority to EP23926655.4A priority patent/EP4672475A4/en
Priority to CN202380049983.5A priority patent/CN119422280A/zh
Publication of WO2024187294A1 publication Critical patent/WO2024187294A1/zh
Priority to US19/281,782 priority patent/US20250379265A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
    • H01M50/457—Separators, membranes or diaphragms characterised by the material having a layered structure comprising three or more layers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/4235—Safety or regulating additives or arrangements in electrodes, separators or electrolyte
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/403—Manufacturing processes of separators, membranes or diaphragms
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/411—Organic material
    • H01M50/414—Synthetic resins, e.g. thermoplastics or thermosetting resins
    • H01M50/417—Polyolefins
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/431—Inorganic material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/431—Inorganic material
    • H01M50/434—Ceramics
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/443—Particulate material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/446—Composite material consisting of a mixture of organic and inorganic materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/409—Separators, membranes or diaphragms characterised by the material
    • H01M50/449—Separators, membranes or diaphragms characterised by the material having a layered structure
    • H01M50/451—Separators, membranes or diaphragms characterised by the material having a layered structure comprising layers of only organic material and layers containing inorganic material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • H01M50/491—Porosity
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/40—Separators; Membranes; Diaphragms; Spacing elements inside cells
    • H01M50/489—Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
    • H01M50/494—Tensile strength
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L50/00—Electric propulsion with power supplied within the vehicle
    • B60L50/50—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells
    • B60L50/60—Electric propulsion with power supplied within the vehicle using propulsion power supplied by batteries or fuel cells using power supplied by batteries
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M2220/00—Batteries for particular applications
    • H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • the present application relates to an isolation film, a battery and an electrical device.
  • the present application provides an isolation membrane, a battery and an electrical device, which can enable the battery to have good cycle performance and kinetic performance.
  • the present application provides an isolation membrane, wherein the isolation membrane comprises a porous substrate and a first coating and a second coating respectively located on two surfaces of the porous substrate, and when used in a battery, the first coating faces the negative electrode and the second coating faces the positive electrode; the first coating comprises first particles, the first particles comprise a solid electrolyte, and the content of the first particles in the first coating is greater than 50 weight %; the second coating comprises second particles, the second particles comprise inorganic particles capable of reacting with lithium dendrites, and the content of the second particles in the second coating is greater than 50 weight %.
  • the isolation membrane provided in the embodiments of the present application can have good heat resistance, mechanical strength, electrolyte wetting characteristics and ion conductivity, and can effectively reduce the probability of internal short circuit of the battery, while also enabling the battery to have good cycle performance and kinetic performance.
  • the content of the first particles in the first coating is greater than or equal to 60% by weight, and can be greater than or equal to 65% by weight, and can be more preferably 65-85% by weight. This enables the first coating to better promote lithium ion transmission and uniform lithium ion flow, thereby helping to reduce the local generation of sharp lithium dendrites, thereby further reducing the probability of internal short circuits in the battery and improving the cycle performance and kinetic performance of the battery.
  • the content of the second particles in the second coating is greater than or equal to 60% by weight, and can be greater than or equal to 65% by weight, and can be more preferably 65-85% by weight. This allows the second coating to better counteract lithium dendrites, consume lithium dendrites in time, slow down or even prevent further growth of lithium dendrites, and further reduce the probability of internal short circuits in the battery and extend the cycle life of the battery.
  • the first coating layer further includes third particles.
  • the third particles include inorganic particles that can react with lithium dendrites.
  • the layer contains a small amount of inorganic particles that can react with lithium dendrites, it can help the first coating layer to react with lithium dendrites, consume lithium dendrites, and slow down the growth of lithium dendrites without affecting the effect of the first coating layer in promoting lithium ion transmission and uniform lithium ion flow, thereby further reducing the probability of internal short circuit in the battery and making the battery have a longer cycle life.
  • the content of the third particles in the first coating layer is greater than 0 and less than or equal to 10 weight %, and may be greater than 0 and less than or equal to 5 weight %.
  • the volume distribution particle size Dv50 of the third particles is 0.05-3 ⁇ m, and can be optionally 0.1-1 ⁇ m.
  • the solid electrolyte includes an inorganic solid electrolyte.
  • the conductivity of the inorganic solid electrolyte is greater than or equal to 10 -7 S/cm, and more optionally greater than or equal to 10 -4 S/cm.
  • the inorganic solid electrolyte includes one or more of an oxide-type inorganic solid electrolyte, a sulfide-type inorganic solid electrolyte, and a halide-type inorganic solid electrolyte.
  • the oxide-type inorganic solid electrolyte includes one or more of a NASICON-type solid electrolyte, a garnet-type solid electrolyte, a perovskite-type solid electrolyte, and a LISICON-type solid electrolyte.
  • the sulfide-type inorganic solid electrolyte includes one or more of a sulfide-type crystalline solid electrolyte and a sulfide glass-type solid electrolyte.
  • the inorganic solid electrolyte includes lithium titanium phosphate (Li x Ti y (PO 4 ) 3 , 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 3), lithium aluminum titanium phosphate (Li x Aly Ti z (PO 4 ) 3 , LATP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum germanium phosphate (Li x Aly Ge z (PO 4 ) 3 , LAGP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum zirconium phosphate (Li x Aly Zr z (PO 4 ) 3 , LAZP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum chromium phosphate (Li x Aly Cr z (PO 4 ) 3 , LACP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), (LiAlTiP)
  • the inorganic solid electrolyte includes one or more of lithium titanium phosphate (Li x Ti y (PO 4 ) 3 , 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 3), lithium aluminum titanium phosphate (Li x Aly Ti z (PO 4 ) 3 , LATP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum germanium phosphate (Li x Aly Ge z (PO 4 ) 3 , LAGP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum zirconium phosphate (Li x Aly Zr z (PO 4 ) 3 , LAZP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum chromium phosphate (Li x Aly Cr z (PO 4 ) 3 , LACP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), and their respective doping compounds.
  • This can better promote lithium ion transmission and uniform lithium ion flow, thereby making lithium deposition more uniform and reducing the local generation of sharp lithium dendrites, which can further reduce the probability of internal short circuit in the battery and improve the battery's cycle performance and kinetic performance.
  • the inorganic particles capable of reacting with lithium dendrites include inorganic ceramic particles.
  • the inorganic ceramic includes aluminum oxide, silicon dioxide, silicon oxide, ferric oxide, ferroferric oxide, cobalt monoxide, cobalt tetroxide, tin oxide, tin dioxide, nickel oxide, iron phosphate, copper oxide, titanium oxide, zirconium oxide, barium oxide, calcium oxide, magnesium oxide, aluminum nitride, silicon nitride, boron nitride, Zirconium titanate, barium titanate, and one or more of their respective modified materials may be selected from aluminum oxide, silicon dioxide, silicon oxide, cobalt monoxide, cobalt tetraoxide, tin oxide, tin dioxide, nickel oxide, iron phosphate, copper oxide, titanium oxide, and one or more of their respective modified materials. This can better react with lithium dendrites, consume lithium dendrites in time, slow down or even prevent further growth of lithium dendrites, and further reduce the probability of internal short circuit of the battery and extend the cycle life of the battery.
  • the volume distribution particle size Dv50 of the first particles is 0.05-3 ⁇ m, and can be optionally 0.1-1 ⁇ m.
  • the volume distribution particle size Dv50 of the first particles is within the above range, it is more conducive to promoting lithium ion transmission and uniform lithium ion flow, and can better slow down or even inhibit the growth of lithium dendrites.
  • the volume distribution particle size Dv50 of the second particles is 0.5-5 ⁇ m, and can be 1-3 ⁇ m.
  • the volume distribution particle size Dv50 of the second particles is within the above range, it can better react with lithium dendrites, consume lithium dendrites in time, and prevent further growth of lithium dendrites.
  • the first coating layer further includes one or more of a first binder, a first dispersant, and a first thickener.
  • the mass ratio of the first particles to the first binder is 100:(1-25), and can be 100:(5-22).
  • An appropriate amount of the first binder can improve the heat resistance and uniformity of the first coating, and can effectively avoid problems such as powdering, and is also conducive to the isolation membrane having good ion conductivity.
  • the mass ratio of the first particles to the first dispersant is 100:(1.0-3.5), and can be 100:(1.2-2.5).
  • An appropriate amount of the first dispersant can make the slurry dispersed evenly, which is beneficial for coating and improving the film quality of the first coating.
  • the mass ratio of the first particles to the first thickener is 100:(10-30), and can be 100:(12-26).
  • An appropriate amount of the first thickener can improve the stability of the slurry, facilitate coating, and improve the film quality of the first coating.
  • the first binder includes one or more of vinylidene fluoride homopolymer and/or copolymer, sodium carboxymethyl cellulose, and styrene-butadiene rubber.
  • the first dispersant includes one or more of hydrolyzed polymaleic anhydride, polyacrylic acid, acrylic acid block copolymer, polyester block copolymer, polyethylene glycol type polyol, polyethylene imine, and their respective derivatives.
  • the first thickener includes one or more of sodium hydroxymethyl cellulose, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl methyl cellulose, polyacrylate, polyurethane, and polyether.
  • the second coating layer further includes one or more of a second binder, a second dispersant, and a second thickener.
  • the mass ratio of the second particles to the second binder is 100:(1-25), and can be 100:(8-22).
  • An appropriate amount of the second binder can improve the heat resistance and uniformity of the second coating, and can effectively avoid problems such as powdering, and is also conducive to the isolation membrane having good ion conductivity.
  • the mass ratio of the second particles to the second dispersant is 100:(0.5-4.0), and can be 100:(1.0-2.0).
  • An appropriate amount of the second dispersant can make the slurry dispersed evenly, which is beneficial for coating and improving the film quality of the second coating.
  • the mass ratio of the second particles to the second thickener is 100:(5-30), and can be 100:(10-25).
  • An appropriate amount of the second thickener can improve the stability of the slurry, facilitate coating, and improve the film quality of the second coating.
  • the second binder includes one or more of vinylidene fluoride homopolymer and/or copolymer, sodium carboxymethyl cellulose, and styrene-butadiene rubber.
  • the second dispersant includes one or more of hydrolyzed polymaleic anhydride, polyacrylic acid, acrylic acid block copolymer, polyester block copolymer, polyethylene glycol type polyol, polyethylene imine, and their respective derivatives.
  • the second thickener includes one or more of sodium hydroxymethylcellulose, methylcellulose, hydroxyethylcellulose, hydroxypropyl methylcellulose, polyacrylate, polyurethane, and polyether.
  • the surface density of the first coating layer is 9-12 g/m 2 , and can be optionally 10-11.5 g/m 2 .
  • the surface density of the first coating layer is within the above range, it is helpful to form a dense and uniform intermediate layer on the surface of the separator, which can better promote the lithium ion transmission and uniform lithium ion flow; it can also make the separator have a lower internal resistance, a shorter lithium ion transmission path and a higher lithium ion transmission rate, so that the battery can have both good cycle performance and kinetic performance.
  • the surface density of the second coating layer is 4-14 g/m 2 , and can be 8-12 g/m 2 .
  • the second coating layer can better react with lithium dendrites, consume lithium dendrites in time, and prevent further growth of lithium dendrites; the separator can also have lower internal resistance, shorter lithium ion transmission path, and higher lithium ion transmission rate, so that the battery can have both good cycle performance and kinetic performance.
  • the ratio of the thickness of the first coating layer to the thickness of the second coating layer is (0.2-5):1, and can be optionally (0.25-4):1.
  • This can better play the role of the first coating layer and the second coating layer, which is beneficial for the first coating layer to better promote lithium ion transmission and uniform lithium ion flow, and is also beneficial for the second coating layer to better react with lithium dendrites, consume lithium dendrites in time, and slow down or even avoid the further growth of lithium dendrites.
  • the probability of internal short circuit of the battery can be further reduced, and the cycle life of the battery can be extended.
  • the thickness of the first coating layer is 1-7 ⁇ m, and can be 1.5-6 ⁇ m.
  • the thickness of the first coating layer is within the above range, it is helpful to form a dense and uniform intermediate layer on the surface of the separator, which can better promote the lithium ion transmission and uniform lithium ion flow; it can also make the separator have a lower internal resistance, a shorter lithium ion transmission path and a higher lithium ion transmission rate, so that the battery can have both good cycle performance and kinetic performance.
  • the thickness of the second coating is 1-7 ⁇ m, and can be 1.5-6 ⁇ m.
  • the second coating can better react with lithium dendrites, consume lithium dendrites in time, and prevent further growth of lithium dendrites; it can also make the isolation film have lower internal resistance, shorter lithium ion transmission path and higher lithium ion transmission rate, so that the battery can have both good cycle performance and kinetic performance.
  • the total thickness of the isolation film is 8-25 ⁇ m, and can be 8-18 ⁇ m, so that the isolation film has lower internal resistance, shorter lithium ion transmission path and higher lithium ion transmission rate, so that the battery has good cycle performance and kinetic performance.
  • the porous substrate comprises polyolefin, halogenated polyolefin, polyamide, poly esters, and their respective derivatives.
  • the thickness of the porous substrate is 4-15 ⁇ m, and optionally 5-10 ⁇ m.
  • the porosity of the isolation membrane is 40%-80%, and optionally 45%-70%.
  • the transverse tensile strength of the isolation film is 1000-1500 kgf/cm 2 , and can be optionally 1100-1300 kgf/cm 2 .
  • the peel strength between the first coating layer of the isolation film and the porous substrate is 8.9-13.2 N/m, and can be 9.1-11.8 N/m.
  • the peel strength between the second coating layer of the isolation film and the porous substrate is 12.9-20.6 N/m, and can be 13.5-17.8 N/m.
  • the puncture strength of the isolation film is 9.60-11.50 N ⁇ m -1 , and can be optionally 9.80-10.90 N ⁇ m -1 .
  • the ionic conductivity of the isolation membrane at 25° C. is 1.40-2.50 mS ⁇ cm ⁇ 1 , and can be optionally 1.60-2.15 mS ⁇ cm ⁇ 1 .
  • the second aspect of the present application provides a battery, including a battery cell and a box body, the battery cell includes a positive electrode plate, a negative electrode plate and the isolation membrane of the first aspect of the present application, and the first coating of the isolation membrane faces the negative electrode plate, and the second coating of the isolation membrane faces the positive electrode plate.
  • the battery cell includes at least one of a lithium-ion battery cell, a lithium metal battery cell, a negative electrode-free lithium metal battery cell, a lithium-sulfur battery cell, and a lithium-air battery cell.
  • a third aspect of the present application provides an electrical device, comprising the battery of the second aspect of the present application.
  • the electric device of the present application includes the battery provided by the present application, and thus has at least the same advantages as the battery.
  • FIG. 1 is a schematic diagram of a battery cell according to an embodiment of the present application.
  • FIG. 2 is an exploded schematic diagram of an embodiment of a battery cell of the present application.
  • FIG. 3 is a schematic diagram of an embodiment of a battery module of the present application.
  • FIG. 4 is a schematic diagram of an embodiment of a battery pack of the present application.
  • FIG. 5 is an exploded schematic diagram of the embodiment of the battery pack shown in FIG. 4 .
  • FIG. 6 is a schematic diagram of an isolation film according to an embodiment of the present application.
  • FIG. 7 is a schematic diagram of an embodiment of an electrical device including the battery of the present application as a power source.
  • “Scope” disclosed in the present application is limited in the form of lower limit and upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range.
  • the scope limited in this way can be including end values or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a specific parameter, it is understood that the scope of 60-110 and 80-120 is also expected.
  • the numerical range "a-b" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers.
  • the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations.
  • a parameter is expressed as an integer ⁇ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.
  • the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially.
  • the method may further include step (c), which means that step (c) may be added to the method in any order.
  • the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.
  • the “include” and “comprising” mentioned in this application represent open-ended or closed-ended expressions.
  • the “include” and “comprising” may represent that other components not listed may also be included or only the listed components may be included or only the listed components may be included.
  • the term "or” is inclusive.
  • the phrase “A or B” means “A, B, or both A and B”. More specifically, any of the following conditions satisfies the condition "A or B”: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).
  • the values of the parameters mentioned in this application can be measured by various test methods commonly used in the art, for example, they can be measured according to the test methods given in the examples of this application. Unless otherwise specified, the test temperature of the parameters is 25°C.
  • the battery mentioned in the embodiments of the present application refers to a battery comprising one or more battery cells to provide a higher voltage and A single physical module with a large capacity.
  • the batteries mentioned in this application may include battery cells, battery modules or battery packs.
  • a battery cell is the smallest unit that makes up a battery, which can realize the function of charging and discharging alone.
  • the present application has no special restrictions on the shape of the battery cell, which can be a cylinder, a cuboid or any other shape.
  • a battery cell 5 of a cuboid structure is used as an example.
  • Multiple battery cells can be connected in series, in parallel or in mixed connection, and mixed connection refers to a mixture of series and parallel connection.
  • multiple battery cells can directly form a battery pack, or they can first form a battery module, and then the battery module can form a battery pack.
  • the battery generally includes a casing for encapsulating one or more battery cells.
  • the casing can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells.
  • the casing can be a simple three-dimensional structure such as a single cuboid, cylinder, or sphere, or a complex three-dimensional structure composed of simple three-dimensional structures such as cuboids, cylinders, or spheres, which is not limited in the embodiments of the present application.
  • the material of the casing can be an alloy material such as aluminum alloy, iron alloy, etc., or a polymer material such as polycarbonate, polyisocyanurate foam plastic, or a composite material such as glass fiber and epoxy resin, which is not limited in the embodiments of the present application.
  • the battery cells mentioned in the embodiments of the present application may be at least one of lithium-ion battery cells, lithium metal battery cells, negative electrode-free lithium metal battery cells, lithium-sulfur battery cells, and lithium-air battery cells.
  • the battery cell provided in the embodiment of the present application includes an electrode assembly and an electrolyte.
  • the electrode assembly includes a positive electrode sheet, a negative electrode sheet, and a separator located between the positive electrode sheet and the negative electrode sheet.
  • the electrode assembly can be a winding structure or a laminated structure, which is not limited in the embodiment of the present application.
  • the battery cell also includes an outer package.
  • the outer package can be used to encapsulate the above-mentioned electrode assembly and electrolyte.
  • the outer package can be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc.
  • the outer package can also be a soft package, such as a bag-type soft package.
  • the material of the soft package can be plastic, such as one or more of polypropylene (PP), polybutylene terephthalate (PBT) and polybutylene succinate (PBS).
  • the outer package may include a shell 51 and a cover plate 53.
  • the shell 51 may include a bottom plate and a side plate connected to the bottom plate, and the bottom plate and the side plate enclose a receiving cavity.
  • the shell 51 has an opening connected to the receiving cavity, and the cover plate 53 is used to cover the opening to close the receiving cavity.
  • the electrode assembly 52 is encapsulated in the receiving cavity.
  • the number of electrode assemblies 52 contained in the battery cell 5 can be one or more, which can be adjusted according to demand.
  • Battery cells can be assembled into battery modules.
  • the number of battery cells contained in a battery module can be multiple, and the specific number can be adjusted according to the application and capacity of the battery module.
  • FIG. 3 is a schematic diagram of a battery module 4 as an example. As shown in FIG. 3 , in a battery module 4, multiple battery cells 5 can be arranged in sequence along the length direction of the battery module 4. Of course, they can also be arranged in any other manner. Further, the multiple battery cells 5 can be fixed by fasteners.
  • the battery module 4 may further include a housing having a housing space, and the plurality of battery cells 5 may be housed in the housing space.
  • FIGS 4 and 5 are schematic diagrams of a battery pack 1 as an example.
  • the battery pack 1 may include a box body and a plurality of battery modules 4 arranged in the box body.
  • the box body includes an upper box body 2 and a lower box body 3, and the upper box body 2 is used to cover the lower box body 3 and form a closed space for accommodating the battery modules 4.
  • Multiple battery modules 4 can be arranged in the box body in any manner.
  • the separator is located between the positive electrode and the negative electrode, and mainly plays the role of preventing short circuits.
  • the separators currently used in commercial batteries are usually porous membranes made of polyolefins (such as polyethylene, polypropylene, etc.).
  • polyolefins such as polyethylene, polypropylene, etc.
  • the electrolyte wettability and Thermal stability is poor.
  • some lithium dendrites will form at the negative electrode interface. The continuous growth of lithium dendrites will pierce the isolation membrane, causing internal short circuits, and even fire, explosion and other safety accidents in severe cases.
  • the inventors have improved the isolation membrane.
  • FIG. 6 is a schematic diagram of an isolation membrane according to an embodiment of the present application.
  • the separator 10 includes a porous substrate 101 and a first coating 102 and a second coating 103 respectively disposed on two surfaces of the porous substrate 101.
  • the first coating 102 faces the negative electrode and the second coating 103 faces the positive electrode.
  • the first coating 102 includes first particles, the first particles include a solid electrolyte, and the content of the first particles in the first coating is greater than 50% by weight;
  • the second coating 102 includes second particles, the second particles include inorganic particles capable of reacting with lithium dendrites, and the content of the second particles in the second coating is greater than 50% by weight.
  • the first coating mainly includes a solid electrolyte.
  • the solid electrolyte itself has a high ionic conductivity and a low electronic conductivity, so it can have good ionic conductivity and electronic insulation. When used in the first coating, it will not significantly increase the impedance of the isolation membrane, and can also reduce the transfer of electrons through the isolation membrane.
  • the first coating faces the negative electrode and can form a dense and uniform intermediate layer on the surface of the isolation membrane, which promotes lithium ion transmission and uniform lithium ion flow, thereby inducing uniform lithium deposition, slowing down or even inhibiting the growth of lithium dendrites, and effectively reducing the local generation of sharp lithium dendrites, thereby reducing or even avoiding the problem of internal short circuit of the battery due to lithium dendrites piercing the isolation membrane.
  • the second coating faces the positive electrode and mainly includes inorganic particles that can react with lithium dendrites. Therefore, when the lithium dendrites generated on the surface of the negative electrode pierce the porous substrate during repeated charging and discharging, the second coating can react with the lithium dendrites, consume the lithium dendrites in time, and prevent the further growth of the lithium dendrites, thereby reducing or even avoiding the problem of internal short circuit of the battery caused by lithium dendrites contacting the positive electrode.
  • the first coating and the second coating are respectively located on both sides of the porous substrate, and there is no interface between the first coating and the second coating in the isolation membrane. Since the ionic conductivity of the first particle and the second particle is different, when the first coating and the second coating are located on the same side of the porous substrate, the concentration of lithium ions at the interface between the first coating and the second coating is different. The inventors have noticed that when the interface concentration difference is too large, it is easy to cause the formation of lithium dendrites, which will increase the probability of internal short circuit of the battery and reduce the service life of the battery.
  • the isolation membrane provided by the embodiment of the present application does not have an interface between the first coating and the second coating, thereby avoiding the problem of lithium dendrites formed due to excessive interface concentration difference.
  • the porous substrate is highly hydrophobic, and the electrolyte usually uses a polar solvent, which results in poor electrolyte wettability of the porous substrate and high ion transfer impedance.
  • the first coating and the second coating introduced in the isolation membrane provided in the embodiment of the present application have good compatibility with the electrolyte, thereby improving the isolation membrane's wetting characteristics for the electrolyte and reducing the isolation membrane's ion transfer impedance, thereby helping the battery to have good cycle performance and kinetic performance.
  • the first coating and the second coating introduced in the isolation membrane provided in the embodiment of the present application can also improve the heat resistance and mechanical strength of the isolation membrane.
  • the isolation membrane provided by the embodiments of the present application can have good heat resistance, mechanical strength, electrolyte wetting characteristics and ion conductivity, and can effectively reduce the probability of internal short circuit of the battery, while also enabling the battery to have good cycle performance and kinetic performance.
  • the first particles include a solid electrolyte, and the content of the first particles is greater than 50% by weight.
  • the first coating mainly include a solid electrolyte, it can promote lithium ion transmission and uniform lithium ion flow, thereby making lithium deposition more uniform, reducing local generation of sharp lithium dendrites, and further reducing the probability of internal short circuits in the battery, while also allowing the battery to have good cycle performance and kinetic performance.
  • the electrolyte content is too low, its effect of promoting lithium ion transmission and uniform lithium ion flow is poor, and thus the effect of slowing down the growth of lithium dendrites is poor, the probability of internal short circuit in the battery is high, and the cycle life of the battery is not good enough.
  • the content of the first particles in the first coating layer may be greater than or equal to 60% by weight, may be greater than or equal to 65% by weight, and may be greater than or equal to 68% by weight. This enables the first coating layer to better promote lithium ion transmission and uniform lithium ion flow, thereby helping to reduce the local generation of sharp lithium dendrites, thereby further reducing the probability of internal short circuits in the battery and improving the cycle performance and kinetic performance of the battery.
  • the content of the first particles in the first coating layer may be 55-90% by weight, 58-90% by weight, 60-90% by weight, 62-90% by weight, 65-90% by weight, 68-90% by weight, 55-88% by weight, 58-88% by weight, 60-88% by weight, 62-88% by weight, 65-88% by weight, 68-88% by weight, 55-85% by weight, 58-85% by weight, 60-85% by weight, 62-85% by weight, 65-85% by weight, 68-85% by weight, 55-82% by weight, 58-82% by weight, 60-82% by weight, 62-82% by weight, 65-82% by weight, 68-82% by weight.
  • the second particles include inorganic particles that can react with lithium dendrites, and the content of the second particles is greater than 50% by weight.
  • the second coating mainly include inorganic particles that can react with lithium dendrites, the second coating can consume lithium dendrites in time, reduce the problem of further growth of lithium dendrites to contact the positive electrode and cause internal short circuit of the battery, thereby reducing the probability of internal short circuit of the battery and extending the cycle life of the battery.
  • the second coating cannot consume lithium dendrites in time, thereby the problem of lithium dendrites piercing the isolation membrane and causing internal short circuit of the battery may occur, and the cycle life of the battery is not excellent enough.
  • the content of the second particles in the second coating layer may be greater than or equal to 60% by weight, may be greater than or equal to 65% by weight, or may be greater than or equal to 68% by weight. This enables the second coating layer to better counteract lithium dendrites, consume lithium dendrites in time, slow down or even prevent further growth of lithium dendrites, thereby further reducing the probability of internal short circuits in the battery and extending the cycle life of the battery.
  • the content of the second particles in the second coating layer may be 55-90 wt%, 58-90 wt%, 60-90 wt%, 62-90 wt%, 65-90 wt%, 55-88 wt%, 58-88 wt%, 68-90 wt%, 60-88 wt%, 62-88 wt%, 65-88 wt%, 68-88 wt%, 55-85 wt%, 58-85 wt%, 60-85 wt%, 62-85 wt%, 65-85 wt%, 68-85 wt%, 55-82 wt%, 58-82 wt%, 60-82 wt%, 62-82 wt%, 65-82 wt%, 68-82 wt%.
  • the solid electrolyte may include an inorganic solid electrolyte.
  • the conductivity of the inorganic solid electrolyte may be greater than or equal to 10 -7 S/cm, and more optionally greater than or equal to 10 -4 S/cm.
  • the inorganic solid electrolyte may include one or more of an oxide-type inorganic solid electrolyte, a sulfide-type inorganic solid electrolyte, and a halide-type inorganic solid electrolyte.
  • the oxide-type inorganic solid electrolyte may include one or more of a NASICON-type solid electrolyte, a garnet-type solid electrolyte, a perovskite-type solid electrolyte, and a LISICON-type solid electrolyte, and may optionally include a NASICON-type solid electrolyte.
  • the NASICON-type solid electrolyte has the advantages of high conductivity and a wide electrochemical window, and can better promote lithium ion transmission and uniform lithium ion flow, thereby making the deposition of lithium more uniform, reducing the local generation of sharp lithium dendrites, and further reducing the probability of internal short circuits in the battery, and improving the cycle performance and kinetic performance of the battery.
  • the sulfide-type inorganic solid electrolyte may include one or more of a sulfide-type crystalline solid electrolyte and a sulfide glass-type solid electrolyte.
  • the inorganic solid electrolyte may include lithium titanium phosphate (Li x Ti y (PO 4 ) 3 , 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 3), phosphoric acid Lithium aluminum titanium (Li x Aly Ti z (PO 4 ) 3 , LATP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum germanium phosphate (Li x Aly Ge z (PO 4 ) 3 , LAGP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum zirconium phosphate (Li x Aly Zr z (PO 4 ) 3 , LAZP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum chromium phosphate (Li x Aly Cr z (PO 4 ) 3 , LACP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), (LiAlTiP)
  • the inorganic solid electrolyte may include one or more of lithium titanium phosphate (Li x Ti y (PO 4 ) 3 , 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 3), lithium aluminum titanium phosphate (Li x Aly Ti z (PO 4 ) 3 , LATP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum germanium phosphate (Li x Aly Ge z (PO 4 ) 3 , LAGP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum zirconium phosphate (Li x Aly Zr z (PO 4 ) 3 , LAZP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), lithium aluminum chromium phosphate (Li x Aly Cr z (PO 4 ) 3 , LACP, 0 ⁇ x ⁇ 2, 0 ⁇ y ⁇ 1, 0 ⁇ z ⁇ 3), and their respective doping compounds.
  • This can better promote lithium ion transmission and uniform lithium ion flow, thereby making lithium deposition more uniform and reducing the local generation of sharp lithium dendrites, which can further reduce the probability of internal short circuit in the battery and improve the battery's cycle performance and kinetic performance.
  • the doped compound is generally a product obtained by doping a compound with other elements, such as metal elements.
  • the type of the doped element is not particularly limited as long as it does not harm the purpose of the present application.
  • lithium titanium phosphate may include LiTi 2 (PO 4 ) 3
  • lithium aluminum titanium phosphate may include Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3
  • lithium aluminum germanium phosphate may include Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3
  • lithium lanthanum titanate may include Li 0.5 La 0.5 TiO 3
  • lithium germanium sulfide electrolyte Li 6 PS 5 X may include Li 6 PS 5 Cl, Li 6 PS 5 Br.
  • the inorganic particles capable of reacting with lithium dendrites may include inorganic ceramic particles.
  • the inorganic ceramic may include one or more of aluminum oxide, silicon dioxide, silicon monoxide, ferric oxide, ferrosinic oxide, cobalt monoxide, cobalt tetroxide, tin oxide, tin dioxide, nickel oxide, iron phosphate, copper oxide, titanium oxide, zirconium oxide, barium oxide, calcium oxide, magnesium oxide, aluminum nitride, silicon nitride, boron nitride, zirconium titanate, barium titanate, and their respective modified materials.
  • the inorganic ceramic may include one or more of aluminum oxide, silicon dioxide, silicon monoxide, cobalt monoxide, cobalt trioxide, tin monoxide, tin dioxide, nickel oxide, iron phosphate, copper oxide, titanium oxide, and their respective modified materials. This can better react with lithium dendrites, consume lithium dendrites in time, slow down or even prevent further growth of lithium dendrites, and further reduce the probability of internal short circuit of the battery and extend the cycle life of the battery.
  • the modification methods include physical modification and/or chemical modification.
  • Chemical modification includes coupling agent modification (such as using silane coupling agent, titanate coupling agent, etc.), surfactant modification, polymer grafting modification, etc.
  • Physical modification methods can be mechanical force dispersion, ultrasonic dispersion, high energy treatment, etc.
  • the volume distribution particle size Dv50 of the first particles may be 0.05-3 ⁇ m, optionally 0.05-2 ⁇ m, 0.08-2 ⁇ m, 0.1-2 ⁇ m, or 0.1-1 ⁇ m.
  • the volume distribution particle size Dv50 of the first particles is within the above range, it is more conducive to promoting lithium ion transmission and uniform lithium ion flow, and can better slow down or even inhibit the growth of lithium dendrites. And it can effectively avoid the following situations: when the particle size of the first particles is too large, the slurry viscosity is high, the uniformity cannot be guaranteed, and it is difficult to evenly apply to multiple When the particle size of the first particles is too small, the first particles are more likely to enter the pores of the porous substrate during the coating process, which not only reduces the air permeability of the isolation membrane, but also hinders the transmission of lithium ions, thereby increasing the capacity loss of the battery and shortening the cycle life.
  • the volume distribution particle size Dv50 of the second particles may be 0.5-5 ⁇ m, optionally 0.5-4 ⁇ m, 0.8-4 ⁇ m, or 1-3 ⁇ m.
  • the volume distribution particle size Dv50 of the second particles is within the above range, it can better react with lithium dendrites, consume lithium dendrites in time and prevent further growth of lithium dendrites. And it can effectively avoid the following situations: when the particle size of the second particles is too large, the viscosity of the slurry is large, the uniformity cannot be guaranteed, it is difficult to evenly coat it on the porous substrate, and during the coating process, the second particles are difficult to adhere to the surface of the porous substrate, and powdering is prone to occur, resulting in poor coating effect, and also affecting the electrochemical performance of the battery; when the particle size of the second particles is too small, the second particles are more likely to enter the pores of the porous substrate during the coating process, which not only reduces the air permeability of the isolation membrane, but also loses the effect of the second coating layer to eliminate lithium dendrites, thereby increasing the capacity loss of the battery and shortening the cycle life.
  • the first coating layer may further include third particles.
  • the content of the third particles in the first coating layer may be greater than 0 and less than or equal to 10 wt %, or may be greater than 0 and less than or equal to 5 wt %.
  • the third particles may include inorganic particles that can react with lithium dendrites.
  • the first coating layer includes a small amount of inorganic particles that can react with lithium dendrites, it can help the first coating layer to react with lithium dendrites, consume lithium dendrites, and slow down the growth of lithium dendrites without affecting the effect of the first coating layer in promoting lithium ion transmission and uniform lithium ion flow, thereby further reducing the probability of internal short circuits in the battery and making the battery have a longer cycle life.
  • the volume distribution particle size Dv50 of the third particles may be 0.05-3 ⁇ m, and may be 0.1-1 ⁇ m.
  • the ratio of the thickness of the first coating layer to the thickness of the second coating layer may be (0.2-5):1, and may be (0.25-4):1. This can better exert the effects of the first coating layer and the second coating layer, which is beneficial for the first coating layer to better promote lithium ion transmission and uniform lithium ion flow, and is also beneficial for the second coating layer to better react with lithium dendrites, consume lithium dendrites in time, slow down or even prevent further growth of lithium dendrites, thereby further reducing the probability of internal short circuit of the battery and extending the cycle life of the battery.
  • the first coating may further include a first binder.
  • the present application has no particular limitation on the type of the first binder.
  • the first binder may include, but is not limited to, one or more of vinylidene fluoride homopolymer (PVDF) and/or copolymer, sodium carboxymethyl cellulose, and styrene-butadiene rubber.
  • the mass ratio of the first particles to the first binder may be 100:(1-25), and may be 100:(5-22).
  • An appropriate amount of the first binder can improve the heat resistance and uniformity of the first coating, and can effectively avoid problems such as powdering, and is also conducive to the isolation membrane having good ion conductivity.
  • the first coating may further include a first dispersant.
  • the present application has no particular restrictions on the type of the first dispersant.
  • the first dispersant may include, but is not limited to, one or more of hydrolyzed polymaleic anhydride, polyacrylic acid, acrylic acid block copolymers, polyester block copolymers, polyethylene glycol type polyols, polyethyleneimine, and their respective derivatives. Derivatives generally refer to products derived from the replacement of hydrogen atoms or atomic groups in a polymer by other atoms or atomic groups.
  • the mass ratio of the first particles to the first dispersant may be 100:(1.0-3.5), and may be 100:(1.2-2.5).
  • An appropriate amount of the first dispersant can make the slurry dispersed evenly, which is beneficial for coating and improving the film quality of the first coating.
  • the first coating may further include a first thickener.
  • the present application has no particular restrictions on the type of the first thickener.
  • the first thickener may include, but is not limited to, one or more of sodium hydroxymethylcellulose, methylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, polyacrylate, polyurethane, and polyether.
  • the mass ratio of the first particles to the first thickener may be 100:(10-30), and may be 100:(12-26).
  • An appropriate amount of the first thickener can improve the stability of the slurry, facilitate coating, and improve the film quality of the first coating.
  • the thickness of the first coating layer may be 1-7 ⁇ m, optionally 1.5-6 ⁇ m.
  • the thickness of the first coating layer helps to form a dense and uniform intermediate layer on the surface of the isolation membrane, which better promotes lithium ion transmission and uniform lithium ion flow, thereby better inducing uniform lithium deposition, slowing down or even inhibiting the growth of lithium dendrites, and effectively reducing the local generation of sharp lithium dendrites, thereby reducing or even avoiding the problem of internal short circuit of the battery due to lithium dendrites piercing the isolation membrane.
  • the isolation membrane may have a lower internal resistance, a shorter lithium ion transmission path and a higher lithium ion transmission rate, thereby enabling the battery to have both good cycle performance and kinetic performance.
  • the surface density of the first coating layer may be 9-12 g/m 2 , and may be 10-11.5 g/m 2 .
  • the surface density of the first coating layer is within the above range, it is helpful to form a dense and uniform intermediate layer on the surface of the separator, which can better promote the transmission of lithium ions and the uniform flow of lithium ions, thereby better inducing the uniform deposition of lithium, slowing down or even inhibiting the growth of lithium dendrites, and effectively reducing the local generation of sharp lithium dendrites, thereby reducing or even avoiding the problem of internal short circuit of the battery due to lithium dendrites piercing the separator.
  • the separator may have a lower internal resistance, a shorter lithium ion transmission path and a higher lithium ion transmission rate, thereby enabling the battery to have both good cycle performance and kinetic performance.
  • the second coating may further include a second binder.
  • the present application has no particular limitation on the type of the second binder.
  • the second binder may include but is not limited to one or more of vinylidene fluoride homopolymer and/or copolymer, sodium carboxymethyl cellulose, and styrene-butadiene rubber.
  • the mass ratio of the second particles to the second binder may be 100:(1-25), and may be 100:(8-22).
  • An appropriate amount of the second binder can improve the heat resistance and uniformity of the second coating, and can effectively avoid problems such as powdering, and is also conducive to the isolation membrane having good ion conductivity.
  • the second coating may further include a second dispersant.
  • the second dispersant may include, but is not limited to, one or more of hydrolyzed polymaleic anhydride, polyacrylic acid, acrylic acid block copolymers, polyester block copolymers, polyethylene glycol type polyols, polyethyleneimine, and their respective derivatives. Derivatives generally refer to products derived from the replacement of hydrogen atoms or atomic groups in a polymer by other atoms or atomic groups.
  • the mass ratio of the second particles to the second dispersant may be 100:(0.5-4.0), and may be 100:(1.0-2.0).
  • An appropriate amount of the second dispersant can make the slurry dispersed evenly, which is beneficial for coating and improving the film quality of the second coating.
  • the second coating may further include a second thickener.
  • the present application has no particular restrictions on the type of the second thickener.
  • the second thickener may include, but is not limited to, one or more of sodium hydroxymethylcellulose, methylcellulose, hydroxyethylcellulose, hydroxypropyl methylcellulose, polyacrylate, polyurethane, and polyether.
  • the mass ratio of the second particles to the second thickener may be 100:(5-30), and may be 100:(10-25).
  • An appropriate amount of the second thickener can improve the stability of the slurry, facilitate coating, and improve the film quality of the second coating.
  • the thickness of the second coating layer may be 1-7 ⁇ m, and may be 1.5-6 ⁇ m.
  • the second coating layer can better react with lithium dendrites, consume lithium dendrites in time, and prevent further growth of lithium dendrites, thereby effectively reducing or even preventing the problem of internal short circuit of the battery caused by lithium dendrites contacting the positive electrode.
  • the isolation film may have a lower internal resistance, a shorter lithium ion transmission path, and a higher lithium ion transmission rate, thereby enabling the battery to have both good cycle performance and kinetic performance.
  • the surface density of the second coating layer may be 4-14 g/m 2 , and may be 8-12 g/m 2 .
  • the second coating layer can better react with lithium dendrites, consume lithium dendrites in time, and prevent further growth of lithium dendrites, thereby effectively reducing or even preventing the problem of internal short circuit of the battery caused by lithium dendrites contacting the positive electrode.
  • the separator may have a lower internal resistance, a shorter lithium ion transmission path, and a higher lithium ion transmission rate, thereby enabling the battery to have both good cycle performance and kinetic performance.
  • the porous substrate may have a thickness of 4-15 ⁇ m, and optionally 5-10 ⁇ m.
  • the porous substrate may include, but is not limited to, one or more of polyolefins (e.g., polyethylene, polypropylene, etc.), halogenated polyolefins (e.g., polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl chloride, etc.), polyamides, polyesters (e.g., polyethylene terephthalate, etc.), and their respective derivatives.
  • polyolefins e.g., polyethylene, polypropylene, etc.
  • halogenated polyolefins e.g., polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl chloride, etc.
  • polyamides e.g., polyamides, polyesters (e.g., polyethylene terephthalate, etc.), and their respective derivatives.
  • Derivatives usually refer to products derived from the replacement of hydrogen atoms or atomic groups in polymers by other atoms or atomic groups.
  • the porous substrate may have a weight average molecular weight of 100,000-1,000,000.
  • the weight average molecular weight of the porous substrate has a well-known meaning in the art and can be measured by methods known in the art, for example, by gel permeation chromatography (GPC).
  • the total thickness of the separator may be 8-25 ⁇ m, and may be 8-18 ⁇ m, so that the separator has lower internal resistance, shorter lithium ion transmission path and higher lithium ion transmission rate, so that the battery has both good cycle performance and kinetic performance.
  • the porosity of the isolation membrane may be 40%-80%, and optionally 45%-70%, thereby helping the isolation membrane to have good air permeability and high ion transmission capacity.
  • the porosity of the isolation membrane has a well-known meaning in the art and can be measured by methods known in the art. For example, it can be tested with reference to standard GB/T 36363-2018.
  • the tensile strength of the separator in transverse direction (TD) may be 1000-1500 kgf/cm 2 , and may be 1100-1300 kgf/cm 2 , thereby improving the reliability of the battery.
  • the transverse tensile strength of the separator has a well-known meaning in the art and can be measured by methods known in the art.
  • the test can be performed with reference to the standard GB/T 36363-2018.
  • the tensile rate can be 50 mm/min.
  • the peel strength between the first coating layer of the isolation film and the porous substrate may be 8.9-13.2 N/m, and may be 9.1-11.8 N/m.
  • the peel strength between the second coating layer of the isolation film and the porous substrate may be 12.9-20.6 N/m, and may be 13.5-17.8 N/m.
  • the separator has high peel strength, thereby improving the reliability of the battery.
  • the peel strength of the isolation film has a well-known meaning in the art and can be measured by methods known in the art. For example, it can be tested with reference to standard GB/T 36363-2018.
  • the puncture strength of the separator may be 9.60-11.50 N ⁇ m -1 , and may be 9.80-10.90 N ⁇ m -1 , thereby improving the reliability of the battery.
  • the puncture strength of the isolation membrane has a well-known meaning in the art and can be measured by methods known in the art. For example, it can be tested with reference to standard GB/T 36363-2018.
  • the ionic conductivity of the separator at 25° C. may be 1.40-2.50 mS ⁇ cm ⁇ 1 , and may be 1.60-2.15 mS ⁇ cm ⁇ 1 . This can improve the cycle performance and kinetic performance of the battery.
  • the ionic conductivity of the isolation membrane can be obtained through electrochemical impedance spectroscopy experiments.
  • the isolation membrane can be cut into discs of a certain area, dried, placed between two stainless steel electrodes, and sealed to form a button battery after absorbing a sufficient amount of electrolyte, and then an electrochemical impedance spectroscopy experiment is carried out.
  • the resistance Rs of different isolation membrane layers n is measured using the confined symmetric battery electrochemical impedance spectroscopy method as the isolation membrane resistance, and the slope k (corresponding to the resistance of a single-layer isolation membrane) is obtained by plotting Rs and n. According to the resistance of the single-layer isolation membrane, the area of the isolation membrane, and the thickness of the isolation membrane (single-layer thickness), the ionic conductivity of the isolation membrane is calculated.
  • the volume distribution particle size Dv50 of the particles is well known in the art and can be measured using instruments and methods known in the art. For example, it can be tested with a laser particle size analyzer (such as Master Size 3000) in accordance with GB/T 19077-2016.
  • a laser particle size analyzer such as Master Size 3000
  • An embodiment of the present application also provides a method for preparing an isolation film.
  • the preparation method includes the following steps: providing a porous substrate; providing a first coating slurry and a second coating slurry, wherein the first coating slurry includes first particles, the first particles include a solid electrolyte, and the content of the first particles in the first coating after drying is greater than 50% by weight, and the second coating slurry includes second particles, the second particles include inorganic particles that can react with lithium dendrites, and the content of the second particles in the second coating after drying is greater than 50% by weight; the first coating slurry and the second coating slurry are respectively coated on two surfaces of the porous substrate, and after drying, an isolation membrane is obtained.
  • the first coating slurry may further include third particles.
  • the first coating slurry may further include one or more of a first binder, a first dispersant, and a first thickener.
  • the step of providing a first coating slurry may include the following steps: adding first particles, a first dispersant, and optional third particles to a first solvent for primary dispersion to obtain a primary dispersion solution; adding a first thickener to the obtained primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution; adding a first binder to the obtained secondary dispersion solution and stirring evenly to obtain a first coating slurry.
  • the first solvent may include one or more of deionized water, N,N-dimethylformamide (DMF), N-methylpyrrolidone (NMP), N,N-dimethylacetamide (DMAC), and tetrahydrofuran (THF).
  • DMF N,N-dimethylformamide
  • NMP N-methylpyrrolidone
  • DMAC N,N-dimethylacetamide
  • THF tetrahydrofuran
  • the primary dispersion process may be ultrasonic dispersion.
  • the ultrasonic dispersion time is more than 2 hours.
  • stirring is required during the secondary dispersion process.
  • the stirring speed may be 500-1200 rpm, and the stirring time may be 0.5-1.5 h.
  • the stirring time can be 0.5-1.5h at a rotation speed of 500-1200rpm.
  • the solid content of the first coating slurry may be 30%-50%, and optionally 34%-45%, which is beneficial for coating.
  • the second coating slurry may further include one or more of a second binder, a second dispersant, and a second thickener.
  • the step of providing a second coating slurry may include the following steps: adding second particles and a second dispersant to a second solvent for primary dispersion to obtain a primary dispersion solution; adding a second thickener to the primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution; adding a second binder to the secondary dispersion solution and stirring evenly to obtain a second coating slurry.
  • the second solvent may include one or more of deionized water, N,N-dimethylformamide (DMF), N-methylpyrrolidone (NMP), N,N-dimethylacetamide (DMAC), and tetrahydrofuran (THF).
  • DMF N,N-dimethylformamide
  • NMP N-methylpyrrolidone
  • DMAC N,N-dimethylacetamide
  • THF tetrahydrofuran
  • the primary dispersion process may be ultrasonic dispersion.
  • the ultrasonic dispersion time is more than 2 hours.
  • stirring is required during the secondary dispersion process.
  • the stirring speed may be 500-1200 rpm, and the stirring time may be 0.5-1.5 h.
  • the mixture may be stirred at a rotation speed of 500-1200 rpm for 0.5-1.5 h.
  • the solid content of the second coating slurry is 30%-50%, and optionally 34%-45%, which is beneficial for coating.
  • the drying temperature may be 60-120°C.
  • the coating method of the first coating slurry and the second coating slurry can be transfer coating, rotary spraying, dip coating, wire rod coating, etc., which is not limited in the embodiments of the present application.
  • Some parameters such as raw materials and their contents used in the method for preparing the isolation membrane provided in the embodiment of the present application can refer to the isolation membrane of the first aspect of the implementation method of the present application, and will not be repeated here.
  • the structure and composition of the positive electrode plate can be selected according to the type of battery cell, and the embodiments of the present application are not limited to this.
  • the positive electrode sheet includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector and including a positive electrode active material.
  • the positive electrode current collector has two surfaces opposite to each other in its thickness direction, and the positive electrode film layer is disposed on any one or both of the two opposite surfaces of the positive electrode current collector.
  • the positive electrode active material includes a material capable of extracting and inserting lithium ions.
  • the positive electrode active material may include, but is not limited to, one or more of lithium transition metal oxides, lithium-containing phosphates, layered metal chalcogenides, and their respective modified compounds.
  • lithium transition metal oxides may include, but are not limited to, one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, lithium titanium oxide, and their respective modified compounds.
  • the positive electrode active material may include one or more of lithium transition metal oxides and modified compounds thereof of the general formula Li a Ni b Co c M d O e D f. 0.8 ⁇ a ⁇ 1.2, 0.5 ⁇ b ⁇ 1, 0 ⁇ c ⁇ 1, 0 ⁇ d ⁇ 1, 1 ⁇ e ⁇ 2, 0 ⁇ f ⁇ 1, M includes one or more of Ge, Mo, Sn, Mn, Al, Zr, Zn, Cu, Cr, Mg, Fe, V, Ti and B, and D includes one or more of N, F, S and Cl.
  • the modified compounds of the above-mentioned positive electrode active materials may be the ones that undergo doping modification and/or surface coating modification on the positive electrode active materials.
  • the positive electrode film layer may further include a positive electrode conductive agent.
  • a positive electrode conductive agent includes one or more of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.
  • the positive electrode film layer may further optionally include a positive electrode binder.
  • a positive electrode binder may include one or more of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, fluorine-containing acrylic resin, and polyethylene oxide.
  • PVDF polyvinylidene fluoride
  • PTFE polytetrafluoroethylene
  • PTFE polytetrafluoroethylene
  • vinylidene fluoride-tetrafluoroethylene-propylene terpolymer vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer
  • the positive electrode current collector may be a metal foil or a composite current collector.
  • a metal foil aluminum foil may be used.
  • the composite current collector may include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer.
  • the metal material may include one or more of aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy.
  • the polymer material base layer may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS) and polyethylene (PE).
  • the positive electrode film layer is usually formed by coating the positive electrode slurry on the positive electrode current collector, drying and cold pressing.
  • the positive electrode slurry is usually formed by dispersing the positive electrode active material, optional conductive agent, optional binder and any other components in a solvent and stirring them uniformly.
  • the solvent can be N-methylpyrrolidone (NMP), but is not limited thereto.
  • the structure and composition of the negative electrode plate can be selected according to the type of battery cell, and the embodiments of the present application are not limited to this.
  • the negative electrode sheet may include a negative electrode current collector and a negative electrode film layer disposed on at least one surface of the negative electrode current collector, the negative electrode film layer includes a negative electrode active material, and the negative electrode active material includes a material capable of extracting and embedding active ions.
  • the negative electrode current collector has two surfaces opposite to each other in its thickness direction, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector.
  • the negative electrode active material may be a negative electrode active material known in the art.
  • the negative electrode active material may include, but is not limited to, one or more of carbon-based materials, silicon-based materials, tin-based materials, and lithium titanate.
  • the carbon-based material may include one or more of natural graphite, artificial graphite, soft carbon, hard carbon, pyrolytic carbon, coke, glassy carbon, a sintered body of an organic polymer compound, and mesophase carbon microbeads.
  • the silicon-based material may include elemental silicon, silicon oxide, silicon-carbon composite, One or more of silicon-nitrogen complex and silicon alloy material.
  • the tin-based material may include one or more of elemental tin, tin oxide and tin alloy material.
  • the negative electrode film layer may further include a negative electrode conductive agent.
  • a negative electrode conductive agent may include one or more of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.
  • the negative electrode film layer may further include a negative electrode binder.
  • the negative electrode binder may include styrene-butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (e.g., polyacrylic acid PAA, polymethacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA) and carboxymethyl chitosan (CMCS).
  • SBR styrene-butadiene rubber
  • SR-1B water-soluble unsaturated resin
  • PAM polyacrylamide
  • PVA polyvinyl alcohol
  • SA sodium alginate
  • CMCS carboxymethyl chitosan
  • the negative electrode film layer may further include other additives, such as, for example, a thickener, such as sodium carboxymethyl cellulose (CMC), a PTC thermistor material, and the like.
  • a thickener such as sodium carboxymethyl cellulose (CMC), a PTC thermistor material, and the like.
  • the negative electrode current collector may be a metal foil or a composite current collector.
  • a metal foil a copper foil may be used.
  • the composite current collector may include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer.
  • the metal material may include one or more of copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver and silver alloy.
  • the polymer material base layer may include one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS) and polyethylene (PE).
  • the negative electrode film layer is usually formed by coating the negative electrode slurry on the negative electrode current collector, drying and cold pressing.
  • the negative electrode slurry is usually formed by dispersing the negative electrode active material, optional conductive agent, optional binder, and other optional auxiliary agents in a solvent and stirring them uniformly.
  • the solvent can be N-methylpyrrolidone (NMP) or deionized water, but is not limited thereto.
  • the negative electrode plate does not exclude other additional functional layers besides the negative electrode film layer.
  • the negative electrode plate also includes a conductive primer layer (e.g., composed of a conductive agent and a binder) sandwiched between the negative electrode current collector and the negative electrode film layer and disposed on the surface of the negative electrode current collector.
  • the negative electrode plate also includes a protective layer covering the surface of the negative electrode film layer.
  • the negative electrode plate may not include materials capable of extracting and embedding active ions, such as graphite, etc.
  • the negative electrode plate may include a lithium plate or a lithium alloy plate; in other embodiments, the negative electrode plate includes a mesh or foam three-dimensional skeleton layer, such as foamed copper (or copper alloy), foamed nickel (or nickel alloy), copper (or copper alloy) mesh, nickel (or nickel alloy) mesh, etc.
  • the electrolyte includes electrolyte salt and solvent.
  • the types of electrolyte salt and solvent are not specifically limited and can be selected according to actual needs.
  • the electrolyte salt may include, but is not limited to, one or more of lithium hexafluorophosphate (LiPF 6 ), lithium tetrafluoroborate (LiBF 4 ), lithium perchlorate (LiClO 4 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium bisfluorosulfonyl imide (LiFSI), lithium bistrifluoromethanesulfonyl imide (LiTFSI), lithium trifluoromethanesulfonate (LiTFS), lithium difluorooxalatoborate (LiDFOB), lithium bisoxalatoborate (LiBOB), lithium difluorophosphate (LiPO 2 F 2 ), lithium difluorobisoxalatophosphate (LiDFOP), and lithium tetrafluorooxalatophosphate (LiTFOP).
  • LiPF 6 lithium hexafluorophosphate
  • the concentration of the electrolyte salt may be greater than 0.3 mol/L, and may be greater than 0.7 mol/L.
  • the concentration of the electrolyte salt may further be less than 4 mol/L, and may be less than 2.5 mol/L or less than 1.7 mol/L.
  • the solvent may include one or more of esters (eg, carbonates, phosphates, carboxylates, sulfates, sulfonates, etc.), ethers, sulfones, nitriles, and the like.
  • esters eg, carbonates, phosphates, carboxylates, sulfates, sulfonates, etc.
  • ethers eg, sulfones, nitriles, and the like.
  • the solvent may include but is not limited to one or more of ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate, ethyl methyl carbonate (EMC), diethyl carbonate (DEC), dimethyl carbonate (DMC), dipropyl carbonate (DPC), methyl propyl carbonate (MPC), ethyl propyl carbonate (EPC), butylene carbonate (BC), fluoroethylene carbonate (FEC), methyl formate (MF), methyl acetate (MA), ethyl acetate (EA), propyl acetate (PA), methyl propionate (MP), ethyl propionate (EP), propyl propionate (PP), methyl butyrate (MB), ethyl butyrate (EB), 1,4-butyrolactone (GBL), cyclopentane (SF), dimethyl sulfone (MSM), dimethyl sulfone (MSM), dimethyl sulfone (MSM
  • the solvent may include an ether solvent and/or a fluoroether solvent, such as dimethyl ether tetraethylene glycol (TEGDME), ethylene glycol dimethyl ether (DME), 1,3-dioxolane (DOL), H(CF 2 ) 2 OCH 3 , C 4 F 9 OCH 3 , H(CF 2 ) 2 OCH 2 CH 3 , H(CF 2 ) 2 OCH 2 CF 3 , H(CF 2 ) 2 CH 2 O(CF 2 ) 2 H, CF 3 CHFCF 2 OCH 3 , CF 3 CHFCF 2 OCH 2 CH 3 .
  • TEGDME dimethyl ether tetraethylene glycol
  • DME ethylene glycol dimethyl ether
  • DOL 1,3-dioxolane
  • the electrolyte may also optionally include additives.
  • the additives may include negative electrode film-forming additives, positive electrode film-forming additives, and additives that can improve certain battery properties, such as additives that improve battery overcharge performance, additives that improve battery high temperature performance, and additives that improve battery low temperature power performance.
  • the embodiments of the present application also provide an electrical device, which includes the battery of the present application.
  • the battery can be used as a power source for the electrical device, or as an energy storage unit for the electrical device.
  • the electrical device can be, but is not limited to, a mobile device (such as a mobile phone, a laptop computer, etc.), an electric vehicle (such as a pure electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, an electric bicycle, an electric scooter, an electric golf cart, an electric truck, etc.), an electric train, a ship and a satellite, an energy storage system, etc.
  • the electrical device can select a specific type of battery according to its usage requirements, such as a battery cell, a battery module or a battery pack.
  • Fig. 7 is a schematic diagram of an electric device as an example.
  • the electric device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc.
  • a battery pack or a battery module can be used as a power source.
  • the electric device may be a mobile phone, a tablet computer, a notebook computer, etc.
  • the electric device is usually required to be light and thin, and a battery cell may be used as a power source.
  • the isolation membranes of Examples 1-27 were all prepared according to the following method.
  • a 7 ⁇ m thick polyethylene porous membrane was washed with ethanol or acetone, dried and flattened at 60° C., and then plasma treated for 4 minutes to obtain a porous substrate for standby use.
  • the first particles, the third particles, the first dispersant acrylic block copolymer and the first solvent NMP shown in Table 1 are mixed, and ultrasonically dispersed in an ultrasonic cleaning machine for 2 hours to obtain a primary dispersion solution.
  • the first thickener sodium hydroxymethyl cellulose is added to the obtained primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution, the stirring speed is 1100rpm, and the stirring time is 1h.
  • the first binder PVDF is added to the obtained secondary dispersion solution, stirred at 900rpm for 60min, and the first coating slurry is obtained after the end.
  • Example 1-27 the mass ratios of the first particles, the third particles, the first binder, the first thickener, and the first dispersant are shown in Table 1.
  • Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 is abbreviated as LATP
  • LiTi 2 (PO 4 ) 3 is abbreviated as LTP
  • Li 7 La 3 Zr 2 O 12 is abbreviated as LLZO.
  • the second particles shown in Table 1, the second dispersant acrylic block copolymer and the second solvent NMP are mixed, and ultrasonically dispersed in an ultrasonic cleaning machine for 2 hours to obtain a primary dispersion solution.
  • the second thickener sodium hydroxymethyl cellulose is added to the obtained primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution, the stirring speed is 1100rpm, and the stirring time is 1h.
  • the second binder PVDF is added to the obtained secondary dispersion solution, stirred at 900rpm for 60min, and the second coating slurry is obtained after the end.
  • the mass ratios of the second particles, the second binder, the second thickener, and the second dispersant are shown in Table 1.
  • the first coating slurry and the second coating slurry were coated on both sides of the porous substrate by wire rod coating, and vacuum dried at 60° C. for 30 minutes to obtain a separator.
  • the thickness of the first coating and the second coating are shown in Table 1.
  • a 7 ⁇ m thick polyethylene porous membrane was washed with ethanol or acetone, dried and flattened at 60° C., and then plasma treated for 4 minutes to obtain a porous substrate for standby use.
  • Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 , dispersant acrylic acid block copolymer and solvent NMP were mixed, and ultrasonically dispersed in an ultrasonic cleaning machine for 2 hours to obtain a primary dispersion solution.
  • Thickener sodium hydroxymethyl cellulose was added to the obtained primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution, with a stirring speed of 1100 rpm and a stirring time of 1 hour.
  • Binder PVDF was added to the obtained secondary dispersion solution, and stirred at 900 rpm for 60 minutes to obtain a coating slurry.
  • the mass ratio of Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 , binder, thickener and dispersant was 100:25.0:2.5:30.0.
  • the coating slurry was coated on both sides of the porous substrate by wire rod coating, and vacuum dried at 60° C. for 30 minutes to obtain a separator.
  • the thickness of the coating on both sides of the porous substrate was 4 ⁇ m.
  • a 7 ⁇ m thick polyethylene porous membrane was washed with ethanol or acetone, dried and flattened at 60° C., and then plasma treated for 4 minutes to obtain a porous substrate for standby use.
  • SiO particles, dispersant acrylic block copolymer and solvent NMP were mixed and ultrasonically dispersed in an ultrasonic cleaning machine for 2 hours to obtain a primary dispersion solution.
  • Thickener sodium hydroxymethyl cellulose was added to the obtained primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution, with a stirring speed of 1100 rpm and a stirring time of 1 hour.
  • Binder PVDF was added to the obtained secondary dispersion solution, and stirred at 900 rpm for 60 minutes to obtain a coating slurry.
  • the mass ratio of SiO particles, binder, thickener and dispersant was 100:25.0:2.5:30.0.
  • the coating slurry was coated on both sides of the porous substrate by wire rod coating, and vacuum dried at 60° C. for 30 minutes to obtain a separator.
  • the thickness of the coating on both sides of the porous substrate was 4 ⁇ m.
  • a 7 ⁇ m thick polyethylene porous membrane was washed with ethanol or acetone, dried and flattened at 60° C., and then plasma treated for 4 minutes to obtain a porous substrate for standby use.
  • the first thickener sodium hydroxymethyl cellulose is added to the obtained primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution, the stirring speed is 1100 rpm, and the stirring time is 1 hour.
  • the first binder PVDF is added to the obtained secondary dispersion solution, and stirred at 900 rpm for 60 minutes, and the first coating slurry is obtained after the end.
  • the mass ratio of the first particle, the first binder, the first thickener, and the first dispersant is 100:65:5:75.
  • the second particle SiO volume distribution particle size Dv50 is 1 ⁇ m
  • the second dispersant acrylic block copolymer and the second solvent NMP are mixed, and ultrasonically dispersed in an ultrasonic cleaning machine for 2 hours to obtain a primary dispersion solution.
  • the second thickener sodium hydroxymethyl cellulose is added to the obtained primary dispersion solution for secondary dispersion to obtain a secondary dispersion solution, the stirring speed is 1100 rpm, and the stirring time is 1 hour.
  • the second binder PVDF is added to the obtained secondary dispersion solution, and stirred at 900 rpm for 60 minutes, and the second coating slurry is obtained after the end.
  • the mass ratio of the second particle, the second binder, the second thickener, and the second dispersant is 100:65:5:75.
  • the first coating slurry and the second coating slurry were coated on both sides of the porous substrate by wire rod coating, and vacuum dried at 60° C. for 30 minutes to obtain a separator.
  • the thickness of the first coating and the second coating were both 4 ⁇ m.
  • the preparation method of the isolation film is the same as that of Example 1, except that when the isolation film is used in a battery, The first coating layer of the separator prepared in Example 1 was arranged to face the positive electrode, and the second coating layer was arranged to face the negative electrode.
  • the tensile strength of the isolation film in the transverse direction is tested.
  • the isolation film is cut into samples with a width of 10 mm and a length of 150 mm (the length direction is parallel to the transverse direction of the isolation film) for testing.
  • the test instrument can be a universal tensile machine, and the tensile rate can be 50 mm/min.
  • the number of isolation film samples can be more than 6, and the test results are averaged.
  • the puncture strength of the isolation membrane is tested according to GB/T 36363-2018.
  • the isolation membrane is cut into samples with a width of 10mm and a length of 150mm.
  • the isolation membrane is punctured with a steel needle at a rate of 50mm/min, and the maximum load when the steel needle penetrates the isolation membrane is read.
  • the number of isolation membrane samples can be more than 6, and 3 points are taken for each isolation membrane sample, and the test results are averaged.
  • the diameter of the steel needle can be 1mm, and the radius of the spherical top can be 0.5mm.
  • the surface of the steel needle is smooth, free of rust, oxide layer and oil stains.
  • the ionic conductivity of the isolation membrane was obtained by electrochemical impedance spectroscopy experiment test. Specifically, the isolation membrane was cut into discs with a diameter of 22 mm, dried, placed between two stainless steel electrodes, and sealed to form a button battery after absorbing a sufficient amount of electrolyte.
  • the electrochemical impedance spectroscopy experiment was carried out using an electrochemical workstation.
  • the electrolyte salt of the electrolyte is LiDFOB with a concentration of 1.2 mol/L; the solvent of the electrolyte is a mixture of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) with a mass ratio of 30:70.
  • the resistance Rs of different isolation membrane layers n was measured using the confined symmetric battery electrochemical impedance spectroscopy method as the isolation membrane resistance.
  • the slope k (corresponding to the resistance of a single-layer isolation membrane) was obtained by plotting Rs and n.
  • the ionic conductivity of the isolation membrane was calculated based on the resistance of the single-layer isolation membrane, the area of the isolation membrane, and the thickness of the isolation membrane (single-layer thickness).
  • the electrochemical workstation can be Shanghai Chenhua CHI 660C electrochemical workstation, the AC signal frequency range is 0.01Hz to 1MHz, and the sine wave potential amplitude is 5mV. For accuracy, the average value of 6 parallel samples is taken as the test result.
  • the button cell can be prepared as follows.
  • Lithium iron phosphate, conductive agent carbon black (Super P), and binder polyvinylidene fluoride (PVDF) were mixed evenly in an appropriate amount of solvent N-methylpyrrolidone (NMP) at a mass ratio of 8:1:1 to obtain a positive electrode slurry; the positive electrode slurry was coated on the positive electrode current collector aluminum foil and dried to obtain a positive electrode plate.
  • NMP solvent N-methylpyrrolidone
  • the positive electrode plate, isolation membrane, and lithium sheet were assembled into a CR2430 button cell.
  • the electrolyte salt of the electrolyte was LiDFOB with a concentration of 1.2 mol/L; the solvent of the electrolyte was a mixture of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) with a mass ratio of 30:70.
  • EC ethylene carbonate
  • EMC ethyl methyl carbonate
  • the first coating layers of the separators of Examples 1-27 and Comparative Examples 1-3 all face the lithium sheet, and the second coating layers all face the positive electrode sheet.
  • Comparative Example 4 uses the same separator as Example 1, except that the first coating layer of the separator prepared in Example 1 is arranged to face the positive electrode sheet, and the second coating layer faces the lithium sheet.
  • the button cell was charged to 3.65V at 0.1C constant current, and then charged to 0.02C at 3.65V constant voltage; after the button cell was left to stand for 10 minutes, it was discharged to 2.5V at 0.1C constant current. After the button cell was cycled twice according to the above method, the following cycle performance test was performed.
  • the button cell was cycled 100 times according to the above method.
  • the average value of the coulombic efficiency of the button cell from the 21st cycle to the 100th cycle was calculated as the average coulombic efficiency of the button cell.
  • Coulombic efficiency discharge capacity / charge capacity.
  • the capacity retention rate of the button cell after 100 cycles discharge capacity at the 100th cycle / discharge capacity at the 20th cycle.
  • the button battery was subjected to a cyclic charge and discharge test according to the above method, and the discharge capacity after each cycle was recorded until the discharge capacity of the button battery decayed to 70% of the discharge capacity of the first cycle. The number of cycles at this time was used to characterize the cycle performance of the battery.
  • the isolation membrane obtained in this way can have both good mechanical strength and good ion conductivity.
  • the isolation membrane provided by the embodiments of the present application can make the battery have good cycle performance and can effectively reduce the probability of internal short circuit of the battery.
  • the cycle performance of the battery can be further improved.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Composite Materials (AREA)
  • Ceramic Engineering (AREA)
  • Cell Separators (AREA)

Abstract

本申请提供一种隔离膜、电池和用电装置，所述隔离膜包括多孔基材以及分别位于所述多孔基材的两个表面上的第一涂层和第二涂层，用于电池时，所述第一涂层面向负极，所述第二涂层面向正极；所述第一涂层包括第一颗粒，所述第一颗粒包括固态电解质，且所述第一涂层中的所述第一颗粒的含量大于50重量％；所述第二涂层包括第二颗粒，所述第二颗粒包括能与锂枝晶反应的无机颗粒，且所述第二涂层中的所述第二颗粒的含量大于50重量％。

Description

隔离膜、电池和用电装置 技术领域
本申请涉及一种隔离膜、电池和用电装置。
背景技术
近年来，电池被广泛应用于水力、火力、风力和太阳能电站等储能电源系统，以及消费电子、电动工具、电动自行车、电动摩托车、电动汽车、军事装备、航空航天等多个领域。随着电池的应用及推广，其可靠性和使用寿命受到越来越多的关注。电池充放电过程中，负极上的枝晶问题是影响电池可靠性和使用寿命的重要原因之一，如何在减缓枝晶生长的同时不影响电池的电化学性能和/或动力学性能是目前亟待解决的技术问题。上述的陈述仅用于提供与本申请有关的背景技术信息，而不必然地构成现有技术。
发明内容
本申请提供一种隔离膜、电池和用电装置，其能使电池具有良好的循环性能和动力学性能。
本申请第一方面提供一种隔离膜，其中，所述隔离膜包括多孔基材以及分别位于所述多孔基材的两个表面上的第一涂层和第二涂层，用于电池时，所述第一涂层面向负极，所述第二涂层面向正极；所述第一涂层包括第一颗粒，所述第一颗粒包括固态电解质，且所述第一涂层中的所述第一颗粒的含量大于50重量％；所述第二涂层包括第二颗粒，所述第二颗粒包括能与锂枝晶反应的无机颗粒，且所述第二涂层中的所述第二颗粒的含量大于50重量％。
本申请的实施例提供的隔离膜可兼具良好的耐热性、机械强度、电解液浸润特性和离子导通能力，并且可以有效降低电池内部短路的概率，同时还可以使电池具有良好的循环性能和动力学性能。
在本申请的任意实施例中，所述第一涂层中的所述第一颗粒的含量大于等于60重量％，可选为大于等于65重量％，更可选为65-85重量％。由此能够使第一涂层更好地起到促进锂离子传输、均匀锂离子流的效果，从而有助于减少局部生成尖锐的锂枝晶，进而可以进一步降低电池内部短路的概率，并提升电池的循环性能和动力学性能。
在本申请的任意实施例中，所述第二涂层中的所述第二颗粒的含量大于等于60重量％，可选为大于等于65重量％，更可选为65-85重量％。由此能够使第二涂层更好地起到与锂枝晶反、及时消耗掉锂枝晶、减缓甚至避免锂枝晶进一步生长的效果，进而可以进一步降低电池内部短路的概率，并延长电池的循环寿命。
在本申请的任意实施例中，所述第一涂层还包括第三颗粒。
在本申请的任意实施例中，所述第三颗粒包括能与锂枝晶反应的无机颗粒。第一涂 层包含少量能与锂枝晶反应的无机颗粒时，能在不影响第一涂层起到促进锂离子传输、均匀锂离子流的效果的前提下，有助于第一涂层还起到与锂枝晶反应、消耗锂枝晶、减缓锂枝晶生长的效果，由此可以进一步降低电池内部短路的概率，并使电池具有更长的循环寿命。
在本申请的任意实施例中，所述第一涂层中的所述第三颗粒的含量大于0且小于等于10重量％，可选为大于0且小于等于5重量％。
在本申请的任意实施例中，所述第三颗粒的体积分布粒径Dv50为0.05-3μm，可选为0.1-1μm。
在本申请的任意实施例中，所述固态电解质包括无机固态电解质，可选地，所述无机固态电解质的电导率大于等于10-7S/cm，更可选为大于等于10-4S/cm。
在本申请的任意实施例中，所述无机固态电解质包括氧化物型无机固态电解质、硫化物型无机固态电解质和卤化物型无机固态电解质中的一种或多种。
在本申请的任意实施例中，所述氧化物型无机固态电解质包括NASICON型固态电解质、石榴石型固态电解质、钙钛矿型固态电解质、LISICON型固态电解质中的一种或多种。
在本申请的任意实施例中，所述硫化物型无机固态电解质包括硫化物型晶态固态电解质和硫化物玻璃型固态电解质中的一种或多种。
在本申请的任意实施例中，所述无机固态电解质包括磷酸钛锂(LixTiy(PO4)3，0<x<2，0<y<3)、磷酸钛铝锂(LixAlyTiz(PO4)3，LATP，0<x<2，0<y<1，0<z<3)、磷酸锗铝锂(LixAlyGez(PO4)3，LAGP，0<x<2，0<y<1，0<z<3)、磷酸锆铝锂(LixAlyZrz(PO4)3，LAZP，0<x<2，0<y<1，0<z<3)、磷酸铬铝锂(LixAlyCrz(PO4)3，LACP，0<x<2，0<y<1，0<z<3)、(LiAlTiP)xOy型玻璃(0<x<4，0<y<13)、钛酸镧锂(LixLayTiO3，0<x<2，0<y<3)、锂澜锆氧化物(Li7La3Zr2O12，LLZO)、锂澜铊氧化物(Li5La3Ta2O12，LLTA)、锂锌锗氧化物(Li14ZnGe4O16)、锂硫银锗矿电解质Li6PS5X(X包括选自Cl、Br、I中的一种或多种)、SiS2型玻璃(LixSiySz，0<x<3，0<y<2，0<z<4)、P2S5型玻璃(LixPySz，0<x<3，0<y<3，0<z<7)、Li3PS4、Li7P3S11、Li10GeP2S12、及其各自的掺杂化合物中的一种或多种。
可选地，所述无机固态电解质包括磷酸钛锂(LixTiy(PO4)3，0<x<2，0<y<3)、磷酸钛铝锂(LixAlyTiz(PO4)3，LATP，0<x<2，0<y<1，0<z<3)、磷酸锗铝锂(LixAlyGez(PO4)3，LAGP，0<x<2，0<y<1，0<z<3)、磷酸锆铝锂(LixAlyZrz(PO4)3，LAZP，0<x<2，0<y<1，0<z<3)、磷酸铬铝锂(LixAlyCrz(PO4)3，LACP，0<x<2，0<y<1，0<z<3)、及其各自的掺杂化合物中的一种或多种。由此可以更好地起到促进锂离子传输、均匀锂离子流的效果，从而可以使得锂的沉积更均匀，减少局部生成尖锐的锂枝晶，进而可以进一步降低电池内部短路的概率，并提升电池的循环性能和动力学性能。
在本申请的任意实施例中，所述能与锂枝晶反应的无机颗粒包括无机陶瓷颗粒。
在本申请的任意实施例中，所述无机陶瓷包括氧化铝、二氧化硅、氧化亚硅、三氧化二铁、四氧化三铁、一氧化钴、四氧化三钴、一氧化锡、二氧化锡、氧化镍、磷酸铁、氧化铜、氧化钛、氧化锆、氧化钡、氧化钙、氧化镁、氮化铝、氮化硅、氮化硼、 钛酸锆、钛酸钡、及其各自的改性材料中的一种或多种，可选为包括氧化铝、二氧化硅、氧化亚硅、一氧化钴、四氧化三钴、一氧化锡、二氧化锡、氧化镍、磷酸铁、氧化铜、氧化钛、及其各自的改性材料中的一种或多种。由此可以更好地起到与锂枝晶反应、及时消耗掉锂枝晶、减缓甚至避免锂枝晶进一步生长的效果，进而可以进一步降低电池内部短路的概率，并延长电池的循环寿命。
在本申请的任意实施例中，所述第一颗粒的体积分布粒径Dv50为0.05-3μm，可选为0.1-1μm。第一颗粒的体积分布粒径Dv50在上述范围内时，更有利于起到促进锂离子传输、均匀锂离子流的效果，并且能够更好地减缓甚至抑制锂枝晶的生长。
在本申请的任意实施例中，所述第二颗粒的体积分布粒径Dv50为0.5-5μm，可选为1-3μm。第二颗粒的体积分布粒径Dv50在上述范围内时，可以更好地起到与锂枝晶反应、及时消耗掉锂枝晶以及避免锂枝晶进一步生长的效果。
在本申请的任意实施例中，所述第一涂层还包括第一粘结剂、第一分散剂和第一增稠剂中的一种或多种。
在本申请的任意实施例中，所述第一颗粒与所述第一粘结剂的质量比为100:(1-25)，可选为100:(5-22)。适量的第一粘结剂可以提升第一涂层的耐热性和均一性，并可以有效避免出现如掉粉等问题，还有利于隔离膜具有良好的离子导通能力。
在本申请的任意实施例中，所述第一颗粒与所述第一分散剂的质量比为100:(1.0-3.5)，可选为100:(1.2-2.5)。适量的第一分散剂可以使得浆料分散均匀，有利于涂布，还有利于提升第一涂层的膜层质量。
在本申请的任意实施例中，所述第一颗粒与所述第一增稠剂的质量比为100:(10-30)，可选为100:(12-26)。适量的第一增稠剂可以提升浆料的稳定性，有利于涂布，还有利于提升第一涂层的膜层质量。
在本申请的任意实施例中，所述第一粘结剂包括偏氟乙烯均聚物和/或共聚物、羧甲基纤维素钠、丁苯橡胶中的一种或多种。
在本申请的任意实施例中，所述第一分散剂包括水解聚马来酸酐、聚丙烯酸、丙烯酸嵌段共聚物、聚酯嵌段共聚物、聚乙二醇型多元醇、聚乙烯亚胺、及其各自的衍生物中的一种或多种。
在本申请的任意实施例中，所述第一增稠剂包括羟甲基纤维素钠、甲基纤维素、羟乙基纤维素、羟丙基甲基纤维素、聚丙烯酸盐、聚氨酯、聚醚中的一种或多种。
在本申请的任意实施例中，所述第二涂层还包括第二粘结剂、第二分散剂和第二增稠剂中的一种或多种。
在本申请的任意实施例中，所述第二颗粒与所述第二粘结剂的质量比为100:(1-25)，可选为100:(8-22)。适量的第二粘结剂可以提升第二涂层的耐热性和均一性，并可以有效避免出现如掉粉等问题，还有利于隔离膜具有良好的离子导通能力。
在本申请的任意实施例中，所述第二颗粒与所述第二分散剂的质量比为100:(0.5-4.0)，可选为100:(1.0-2.0)。适量的第二分散剂可以使得浆料分散均匀，有利于涂布，还有利于提升第二涂层的膜层质量。
在本申请的任意实施例中，所述第二颗粒与所述第二增稠剂的质量比为100:(5-30)，可选为100：(10-25)。适量的第二增稠剂可以提升浆料的稳定性，有利于涂布，还有利于提升第二涂层的膜层质量。
在本申请的任意实施例中，所述第二粘结剂包括偏氟乙烯均聚物和/或共聚物、羧甲基纤维素钠、丁苯橡胶中的一种或多种。
在本申请的任意实施例中，所述第二分散剂包括水解聚马来酸酐、聚丙烯酸、丙烯酸嵌段共聚物、聚酯嵌段共聚物、聚乙二醇型多元醇、聚乙烯亚胺、及其各自的衍生物中的一种或多种。
在本申请的任意实施例中，所述第二增稠剂包括羟甲基纤维素钠、甲基纤维素、羟乙基纤维素、羟丙基甲基纤维素、聚丙烯酸盐、聚氨酯、聚醚中的一种或多种。
在本申请的任意实施例中，所述第一涂层的面密度为9-12g/m2，可选为10-11.5g/m2。第一涂层的面密度在上述范围内时，有助于在隔离膜表面形成致密且均匀的中间层，更好地起到促进锂离子传输、均匀锂离子流的效果；还可以使隔离膜可具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在本申请的任意实施例中，所述第二涂层的面密度为4-14g/m2，可选为8-12g/m2。第二涂层的面密度在上述范围内时，可以使第二涂层更好地起到与锂枝晶反应、及时消耗掉锂枝晶以及避免锂枝晶进一步生长的效果；还可以使隔离膜具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在本申请的任意实施例中，所述第一涂层的厚度与所述第二涂层的厚度之比为(0.2-5):1，可选为(0.25-4):1。由此可以更好地发挥第一涂层和第二涂层的作用效果，有利于第一涂层更好地起到促进锂离子传输、均匀锂离子流的效果，还有利于第二涂层更好地起到与锂枝晶反应、及时消耗掉锂枝晶、减缓甚至避免锂枝晶进一步生长的效果。进而可以进一步降低电池内部短路的概率，并延长电池的循环寿命。
在本申请的任意实施例中，所述第一涂层的厚度为1-7μm，可选为1.5-6μm。第一涂层的厚度在上述范围内时，有助于在隔离膜表面形成致密且均匀的中间层，更好地起到促进锂离子传输、均匀锂离子流的效果；还可以使隔离膜可具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在本申请的任意实施例中，所述第二涂层的厚度为1-7μm，可选为1.5-6μm。第二涂层的厚度在上述范围内时，可以使第二涂层更好地起到与锂枝晶反应、及时消耗掉锂枝晶以及避免锂枝晶进一步生长的效果；还可以使隔离膜具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在本申请的任意实施例中，所述隔离膜的总厚度为8-25μm，可选为8-18μm。由此可以使隔离膜具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，从而可以使电池兼具良好的循环性能和动力学性能。
在本申请的任意实施例中，所述多孔基材包括聚烯烃、卤代聚烯烃、聚酰胺、聚 酯、及其各自的衍生物中的一种或多种。
在本申请的任意实施例中，所述多孔基材的厚度为4-15μm，可选为5-10μm。
在本申请的任意实施例中，所述隔离膜的孔隙率为40％-80％，可选为45％-70％。
在本申请的任意实施例中，所述隔离膜的横向拉伸强度为1000-1500kgf/cm2，可选为1100-1300kgf/cm2。
在本申请的任意实施例中，所述隔离膜的第一涂层与多孔基材的剥离强度为8.9-13.2N/m，可选为9.1-11.8N/m。
在本申请的任意实施例中，所述隔离膜的第二涂层与多孔基材的剥离强度为12.9-20.6N/m，可选为13.5-17.8N/m。
在本申请的任意实施例中，所述隔离膜的穿刺强度为9.60-11.50N·μm-1，可选为9.80-10.90N·μm-1。
在本申请的任意实施例中，所述隔离膜25℃的离子电导率为1.40-2.50mS·cm-1，可选为1.60-2.15mS·cm-1。
本申请第二方面提供一种电池，包括电池单体以及箱体，所述电池单体包括正极极片、负极极片以及本申请第一方面的隔离膜，且所述隔离膜的第一涂层面向所述负极极片，所述隔离膜的第二涂层面向所述正极极片。
在本申请的任意实施例中，所述电池单体包括锂离子电池单体、锂金属电池单体、无负极锂金属电池单体、锂硫电池单体、锂空气电池单体中的至少一种。
本申请第三方面提供一种用电装置，包括本申请第二方面的电池。
本申请的用电装置包括本申请提供的电池，因而至少具有与所述电池相同的优势。
附图说明
为了更清楚地说明本申请实施例的技术方案，下面将对本申请实施例中所需要使用的附图作简单地介绍。显而易见地，下面所描述的附图仅仅是本申请的一些实施方式，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据附图获得其他的附图。
图1是本申请的电池单体的一实施方式的示意图。
图2是本申请的电池单体的一实施方式的分解示意图。
图3是本申请的电池模块的一实施方式的示意图。
图4是本申请的电池包的一实施方式的示意图。
图5是图4所示的电池包的实施方式的分解示意图。
图6是本申请的隔离膜的一实施方式的示意图。
图7是包含本申请的电池作为电源的用电装置的一实施方式的示意图。
在附图中，附图未必按照实际的比例绘制。附图标记说明如下：1电池包，2上箱体，3下箱体，4电池模块，5电池单体，51壳体，52电极组件，53盖板，10隔离膜，101多孔基材，102第一涂层，103第二涂层。
具体实施方式
以下，适当地参照附图详细说明具体公开了本申请的隔离膜、电池和用电装置的实施方式。但是会有省略不必要的详细说明的情况。例如，有省略对已众所周知的事项的详细说明、实际相同结构的重复说明的情况。这是为了避免以下的说明不必要地变得冗长，便于本领域技术人员的理解。此外，附图及以下说明是为了本领域技术人员充分理解本申请而提供的，并不旨在限定权利要求书所记载的主题。
本申请所公开的“范围”以下限和上限的形式来限定，给定范围是通过选定一个下限和一个上限进行限定的，选定的下限和上限限定了特别范围的边界。这种方式进行限定的范围可以是包括端值或不包括端值的，并且可以进行任意地组合，即任何下限可以与任何上限组合形成一个范围。例如，如果针对特定参数列出了60-120和80-110的范围，理解为60-110和80-120的范围也是预料到的。此外，如果列出的最小范围值1和2，和如果列出了最大范围值3，4和5，则下面的范围可全部预料到：1-3、1-4、1-5、2-3、2-4和2-5。在本申请中，除非有其他说明，数值范围“a-b”表示a到b之间的任意实数组合的缩略表示，其中a和b都是实数。例如数值范围“0-5”表示本文中已经全部列出了“0-5”之间的全部实数，“0-5”只是这些数值组合的缩略表示。另外，当表述某个参数为≥2的整数，则相当于公开了该参数为例如整数2、3、4、5、6、7、8、9、10、11、12等。
如果没有特别的说明，本申请的所有实施方式以及可选实施方式可以相互组合形成新的技术方案，并且这样的技术方案应被认为包含在本申请的公开内容中。
如果没有特别的说明，本申请的所有技术特征以及可选技术特征可以相互组合形成新的技术方案，并且这样的技术方案应被认为包含在本申请的公开内容中。
如果没有特别的说明，本申请的所有步骤可以顺序进行，也可以随机进行，优选是顺序进行的。例如，所述方法包括步骤(a)和(b)，表示所述方法可包括顺序进行的步骤(a)和(b)，也可以包括顺序进行的步骤(b)和(a)。例如，所述提到所述方法还可包括步骤(c)，表示步骤(c)可以任意顺序加入到所述方法，例如，所述方法可以包括步骤(a)、(b)和(c)，也可包括步骤(a)、(c)和(b)，也可以包括步骤(c)、(a)和(b)等。
如果没有特别的说明，本申请所提到的“包括”和“包含”表示开放式，也可以是封闭式。例如，所述“包括”和“包含”可以表示还可以包括或包含没有列出的其他组分，也可以仅包括或包含列出的组分。
如果没有特别的说明，在本申请中，术语“或”是包括性的。举例来说，短语“A或B”表示“A，B，或A和B两者”。更具体地，以下任一条件均满足条件“A或B”：A为真(或存在)并且B为假(或不存在)；A为假(或不存在)而B为真(或存在)；或A和B都为真(或存在)。
如果没有特别的说明，在本申请中，术语“第一”、“第二”、“第三”等是用于区别不同对象，而不是用于描述特定顺序或主次关系。
除非另有说明，本申请中使用的术语具有本领域技术人员通常所理解的公知含义。
除非另有说明，本申请中提到的各参数的数值可以用本领域常用的各种测试方法进行测定，例如，可以按照本申请的实施例中给出的测试方法进行测定。除非另有说明，参数的测试温度均为25℃。
本申请的实施例中所提到的电池是指包括一个或多个电池单体以提供更高的电压和 容量的单一的物理模块。例如，本申请中所提到的电池可以包括电池单体、电池模块或电池包等。电池单体是组成电池的最小单元，其独自能够实现充放电的功能。本申请对电池单体的形状没有特别的限制，其可以是圆柱体、长方体或其他任意的形状。如图1是作为一个示例的长方体结构的电池单体5。多个电池单体之间可以串联或并联或混联，混联是指串联和并联的混合。本申请的实施例中多个电池单体可以直接组成电池包，也可以先组成电池模块，电池模块再组成电池包。
电池一般包括用于封装一个或多个电池单体的箱体。箱体可以避免液体或其他异物影响电池单体的充电或放电。箱体可以是单独的长方体或者圆柱体或球体等简单立体结构，也可以是由长方体或者圆柱体或球体等简单立体结构组合而成的复杂立体结构，本申请实施例对此并不限定。箱体的材质可以是如铝合金、铁合金等合金材料，也可以是如聚碳酸酯、聚异氰脲酸酯泡沫塑料等高分子材料，或者是如玻璃纤维加环氧树脂的复合材料，本申请实施例对此也并不限定。
本申请的实施例中所提到的电池单体可以是锂离子电池单体、锂金属电池单体、无负极锂金属电池单体、锂硫电池单体、锂空气电池单体中的至少一种。
本申请的实施例提供的电池单体包括电极组件和电解液。电极组件包括正极极片、负极极片以及位于正极极片和负极极片之间的隔离膜。电极组件可为卷绕结构或叠片结构，本申请实施例对此并不限定。
电池单体还包括外包装。该外包装可用于封装上述电极组件及电解液。外包装可以是硬壳，例如硬塑料壳、铝壳、钢壳等。外包装也可以是软包，例如袋式软包。软包的材质可以是塑料，如聚丙烯(PP)、聚对苯二甲酸丁二醇酯(PBT)和聚丁二酸丁二醇酯(PBS)中的一种或多种。
如图2所示，外包装可包括壳体51和盖板53。壳体51可包括底板和连接于底板上的侧板，底板和侧板围合形成容纳腔。壳体51具有与容纳腔连通的开口，盖板53用于盖设开口，以封闭容纳腔。电极组件52封装于容纳腔。电池单体5所含电极组件52的数量可以为一个或多个，可根据需求来调节。
电池单体可以组装成电池模块，电池模块所含电池单体的数量可以为多个，具体数量可根据电池模块的应用和容量来调节。图3是作为一个示例的电池模块4的示意图。如图3所示，在电池模块4中，多个电池单体5可以是沿电池模块4的长度方向依次排列设置。当然，也可以按照其他任意的方式进行排布。进一步可以通过紧固件将该多个电池单体5进行固定。
电池模块4还可以包括具有容纳空间的外壳，多个电池单体5容纳于该容纳空间。
上述电池模块还可以组装成电池包，电池包所含电池模块的数量可以根据电池包的应用和容量进行调节。图4和图5是作为一个示例的电池包1的示意图。如图4和图5所示，在电池包1中可以包括箱体和设置于箱体中的多个电池模块4。箱体包括上箱体2和下箱体3，上箱体2用于盖设下箱体3，并形成用于容纳电池模块4的封闭空间。多个电池模块4可以按照任意的方式排布于箱体中。
隔离膜作为电池单体的重要组成部件，其性能对于电池的性能至关重要，隔离膜位于正极极片和负极极片之间，主要起到防止短路的作用。目前商业化电池采用的隔离膜通常为聚烯烃(例如聚乙烯、聚丙烯等)多孔膜，但是，这类隔离膜的电解液浸润性和 热稳定性较差。此外，随着电池充放电次数的增加，负极界面会形成一些锂枝晶，锂枝晶持续生长会刺穿隔离膜，引发内部短路，严重时甚至出现燃烧、爆炸等安全事故。
因此，开发一种热稳定性好、电解液浸润性优良且可靠性高的隔离膜，是本领域亟待解决的技术问题。
鉴于此，发明人对隔离膜进行了改进。
图6是本申请的隔离膜的一实施方式的示意图。
如图6所示，隔离膜10包括多孔基材101以及分别位于多孔基材101的两个表面上的第一涂层102和第二涂层103，用于电池时，第一涂层102面向负极，第二涂层103面向正极。第一涂层102包括第一颗粒，第一颗粒包括固态电解质，且第一涂层中的第一颗粒的含量大于50重量％；第二涂层102包括第二颗粒，第二颗粒包括能与锂枝晶反应的无机颗粒，且第二涂层中的第二颗粒的含量大于50重量％。
第一涂层主要包括固态电解质。固态电解质本身拥有较高的离子电导率和较低的电子导电率，由此可具有较好的离子导通性和电子绝缘性，用于第一涂层时不会大幅增加隔离膜阻抗，且还可以减少电子通过隔离膜进行转移。此外，第一涂层面向负极，可以在隔离膜表面形成致密且均匀的中间层，起到促进锂离子传输、均匀锂离子流的效果，由此可以诱导锂均匀的沉积，减缓甚至抑制锂枝晶的生长，并可以有效减少局部生成尖锐的锂枝晶，进而可以减少甚至避免由于锂枝晶刺破隔离膜而出现电池内部短路的问题。
第二涂层面向正极且主要包括能与锂枝晶反应的无机颗粒，由此当负极表面生成的锂枝晶在反复充放电过程中刺破多孔基材时，第二涂层可以起到与锂枝晶反应、及时消耗掉锂枝晶以及避免锂枝晶进一步生长的效果，由此可以减少甚至避免锂枝晶接触正极而出现电池内部短路的问题。
第一涂层和第二涂层分别位于多孔基材的两侧，隔离膜中不存在第一涂层与第二涂层的界面。由于第一颗粒与第二颗粒的离子电导率不同，从而导致第一涂层与第二涂层位于多孔基材的同侧时，第一涂层与第二涂层界面处锂离子的浓度不同，而发明人注意到，当界面浓度差过大时反而容易导致锂枝晶形成，进而还会增加电池内部短路的概率，降低电池的使用寿命。本申请的实施例提供的隔离膜不存在第一涂层与第二涂层的界面，由此可以避免由于界面浓度差过大而形成锂枝晶的问题。
多孔基材疏水性较强，而电解液通常采用极性溶剂，由此导致多孔基材的电解液浸润性差、离子传输阻抗高。在本申请的实施例提供的隔离膜中引入的第一涂层和第二涂层与电解液的相容性较好，从而能够提升隔离膜对电解液的浸润特性、降低隔离膜的离子传输阻抗，进而有助于电池具有良好的循环性能和动力学性能。此外，在本申请的实施例提供的隔离膜中引入的第一涂层和第二涂层还可以提升隔离膜的耐热性和机械强度。
因此，本申请的实施例提供的隔离膜可兼具良好的耐热性、机械强度、电解液浸润特性和离子导通能力，并且可以有效降低电池内部短路的概率，同时还可以使电池具有良好的循环性能和动力学性能。
在第一涂层中，第一颗粒包括固态电解质，且第一颗粒的含量大于50重量％。通过使第一涂层主要包括固态电解质，可以起到促进锂离子传输、均匀锂离子流的效果，从而可以使得锂的沉积更均匀，减少局部生成尖锐的锂枝晶，进而可以降低电池内部短路的概率，同时还可以使电池具有良好的循环性能和动力学性能。而当第一涂层中的固态 电解质的含量过少时，其对锂离子传输的促进效果以及对锂离子流的均匀效果较差，进而对锂枝晶生长的减缓效果较差，电池内部短路的概率较大，且电池的循环寿命不够优异。
在一些实施例中，第一涂层中的第一颗粒的含量可大于等于60％重量％，可选为大于等于65重量％，更可选为大于等于68重量％。由此能够使第一涂层更好地起到促进锂离子传输、均匀锂离子流的效果，从而有助于减少局部生成尖锐的锂枝晶，进而可以进一步降低电池内部短路的概率，并提升电池的循环性能和动力学性能。例如，第一涂层中的第一颗粒的含量可为55-90重量％，58-90重量％，60-90重量％，62-90重量％，65-90重量％，68-90重量％，55-88重量％，58-88重量％，60-88重量％，62-88重量％，65-88重量％，68-88重量％，55-85重量％，58-85重量％，60-85重量％，62-85重量％，65-85重量％，68-85重量％，55-82重量％，58-82重量％，60-82重量％，62-82重量％，65-82重量％，68-82重量％。
在第二涂层中，第二颗粒包括能与锂枝晶反应的无机颗粒，且第二颗粒的含量大于50重量％。通过使第二涂层主要包括能与锂枝晶反应的无机颗粒，可以使第二涂层及时消耗掉锂枝晶，减少锂枝晶进一步生长接触正极而出现电池内部短路的问题，从而可以降低电池内部短路的概率，同时还可以延长电池的循环寿命。而当能与锂枝晶反应的无机颗粒的含量较少时，第二涂层不能及时消耗掉锂枝晶，由此可能出现锂枝晶刺破隔离膜而导致电池内部短路的问题，且电池的循环寿命不够优异。
在一些实施例中，第二涂层中的第二颗粒的含量可大于等于60％重量％，可选为大于等于65重量％，可选为大于等于68重量％。由此能够使第二涂层更好地起到与锂枝晶反、及时消耗掉锂枝晶、减缓甚至避免锂枝晶进一步生长的效果，进而可以进一步降低电池内部短路的概率，并延长电池的循环寿命。例如，第二涂层中的第二颗粒的含量可为55-90重量％，58-90重量％，60-90重量％，62-90重量％，65-90重量％，55-88重量％，58-88重量％，68-90重量％，60-88重量％，62-88重量％，65-88重量％，68-88重量％，55-85重量％，58-85重量％，60-85重量％，62-85重量％，65-85重量％，68-85重量％，55-82重量％，58-82重量％，60-82重量％，62-82重量％，65-82重量％，68-82重量％。
在一些实施例中，固态电解质可包括无机固态电解质。可选地，无机固态电解质的电导率可大于等于10-7S/cm，更可选为大于等于10-4S/cm。
在一些实施例中，无机固态电解质可包括氧化物型无机固态电解质、硫化物型无机固态电解质和卤化物型无机固态电解质中的一种或多种。
在一些实施例中，氧化物型无机固态电解质可包括NASICON型固态电解质、石榴石型固态电解质、钙钛矿型固态电解质、LISICON型固态电解质中的一种或多种，可选为包括NASICON型固态电解质。NASICON型固态电解质具有电导率高和电化学窗口宽的优势，可以更好地起到促进锂离子传输、均匀锂离子流的效果，从而可以使得锂的沉积更均匀，减少局部生成尖锐的锂枝晶，进而可以进一步降低电池内部短路的概率，并提升电池的循环性能和动力学性能。
在一些实施例中，硫化物型无机固态电解质可包括硫化物型晶态固态电解质和硫化物玻璃型固态电解质中的一种或多种。
作为示例，无机固态电解质可包括磷酸钛锂(LixTiy(PO4)3，0<x<2，0<y<3)、磷酸 钛铝锂(LixAlyTiz(PO4)3，LATP，0<x<2，0<y<1，0<z<3)、磷酸锗铝锂(LixAlyGez(PO4)3，LAGP，0<x<2，0<y<1，0<z<3)、磷酸锆铝锂(LixAlyZrz(PO4)3，LAZP，0<x<2，0<y<1，0<z<3)、磷酸铬铝锂(LixAlyCrz(PO4)3，LACP，0<x<2，0<y<1，0<z<3)、(LiAlTiP)xOy型玻璃(0<x<4，0<y<13)、钛酸镧锂(LixLayTiO3，0<x<2，0<y<3)、锂澜锆氧化物(Li7La3Zr2O12，LLZO)、锂澜铊氧化物(Li5La3Ta2O12，LLTA)、锂锌锗氧化物(Li14ZnGe4O16)、锂硫银锗矿电解质Li6PS5X(X包括选自Cl、Br、I中的一种或多种)、SiS2型玻璃(LixSiySz，0<x<3，0<y<2，0<z<4)、P2S5型玻璃(LixPySz，0<x<3，0<y<3，0<z<7)、Li3PS4、Li7P3S11、Li10GeP2S12、及其各自的掺杂化合物中的一种或多种。可选地，无机固态电解质可包括磷酸钛锂(LixTiy(PO4)3，0<x<2，0<y<3)、磷酸钛铝锂(LixAlyTiz(PO4)3，LATP，0<x<2，0<y<1，0<z<3)、磷酸锗铝锂(LixAlyGez(PO4)3，LAGP，0<x<2，0<y<1，0<z<3)、磷酸锆铝锂(LixAlyZrz(PO4)3，LAZP，0<x<2，0<y<1，0<z<3)、磷酸铬铝锂(LixAlyCrz(PO4)3，LACP，0<x<2，0<y<1，0<z<3)、及其各自的掺杂化合物中的一种或多种。由此可以更好地起到促进锂离子传输、均匀锂离子流的效果，从而可以使得锂的沉积更均匀，减少局部生成尖锐的锂枝晶，进而可以进一步降低电池内部短路的概率，并提升电池的循环性能和动力学性能。
掺杂化合物通常是在化合物中掺杂其他元素，例如金属元素得到的产物。掺杂元素的种类没有特别限制，只要不有损本申请的主旨即可。
例如，磷酸钛锂可包括LiTi2(PO4)3，磷酸钛铝锂可包括Li1.3Al0.3Ti1.7(PO4)3，磷酸锗铝锂可包括Li1.5A10.5Ge1.5(PO4)3，钛酸镧锂可包括Li0.5La0.5TiO3，锂硫银锗矿电解质Li6PS5X可包括Li6PS5Cl、Li6PS5Br。
在一些实施例中，能与锂枝晶反应的无机颗粒可包括无机陶瓷颗粒。
在一些实施例中，无机陶瓷可包括氧化铝、二氧化硅、氧化亚硅、三氧化二铁、四氧化三铁、一氧化钴、四氧化三钴、一氧化锡、二氧化锡、氧化镍、磷酸铁、氧化铜、氧化钛、氧化锆、氧化钡、氧化钙、氧化镁、氮化铝、氮化硅、氮化硼、钛酸锆、钛酸钡、及其各自的改性材料中的一种或多种。
可选地，无机陶瓷可包括氧化铝、二氧化硅、氧化亚硅、一氧化钴、四氧化三钴、一氧化锡、二氧化锡、氧化镍、磷酸铁、氧化铜、氧化钛、及其各自的改性材料中的一种或多种。由此可以更好地起到与锂枝晶反应、及时消耗掉锂枝晶、减缓甚至避免锂枝晶进一步生长的效果，进而可以进一步降低电池内部短路的概率，并延长电池的循环寿命。
改性方式包括物理改性和/或化学改性。化学改性包括偶联剂改性(例如采用硅烷偶联剂、钛酸酯偶联剂等)、表面活性剂改性、聚合物接枝改性等。物理改性方式可为机械力分散、超声分散、高能处理等。
在一些实施例中，第一颗粒的体积分布粒径Dv50可为0.05-3μm，可选为0.05-2μm，0.08-2μm，0.1-2μm，0.1-1μm。
第一颗粒的体积分布粒径Dv50在上述范围内时，更有利于起到促进锂离子传输、均匀锂离子流的效果，并且能够更好地减缓甚至抑制锂枝晶的生长。并且可以有效避免以下情况：第一颗粒的粒径过大时，浆料粘度较大、均匀性不能保证，难以均匀涂布到多 孔基材上，且在涂布过程中第一颗粒难以在多孔基材表面附着，易发生掉粉现象，导致涂布效果较差，同时还会影响电池的电化学性能；第一颗粒的粒径过小时，涂布过程中第一颗粒更易进入多孔基材的孔中，既降低了隔离膜的透气性，又阻碍了锂离子的传输，由此使得电池的容量损失增加、循环寿命变短。
在一些实施例中，第二颗粒的体积分布粒径Dv50可为0.5-5μm，可选为0.5-4μm，0.8-4μm，1-3μm。
第二颗粒的体积分布粒径Dv50在上述范围内时，可以更好地起到与锂枝晶反应、及时消耗掉锂枝晶以及避免锂枝晶进一步生长的效果。并且可以有效避免以下情况：第二颗粒的粒径过大时，浆料粘度较大、均匀性不能保证，难以均匀涂布到多孔基材上，且在涂布过程中第二颗粒难以在多孔基材表面附着，易发生掉粉现象，导致涂布效果较差，同时还会影响电池的电化学性能；第二颗粒的粒径过小时，涂布过程中第二颗粒更易进入多孔基材的孔中，既降低了隔离膜的透气性，又丧失了第二涂层消掉锂枝晶的效果，由此使得电池的容量损失增加、循环寿命变短。
在一些实施例中，第一涂层还可以包括第三颗粒。可选地，第一涂层中的第三颗粒的含量可大于0且小于等于10重量％，可选为大于0且小于等于5重量％。
在一些实施例中，第三颗粒可包括能与锂枝晶反应的无机颗粒。第一涂层包含少量能与锂枝晶反应的无机颗粒时，能在不影响第一涂层起到促进锂离子传输、均匀锂离子流的效果的前提下，有助于第一涂层还起到与锂枝晶反应、消耗锂枝晶、减缓锂枝晶生长的效果，由此可以进一步降低电池内部短路的概率，并使电池具有更长的循环寿命。
在一些实施例中，第三颗粒的体积分布粒径Dv50可为0.05-3μm，可选为0.1-1μm。
在一些实施例中，所述第一涂层的厚度与所述第二涂层的厚度之比可为(0.2-5):1，可选为(0.25-4):1。由此可以更好地发挥第一涂层和第二涂层的作用效果，有利于第一涂层更好地起到促进锂离子传输、均匀锂离子流的效果，还有利于第二涂层更好地起到与锂枝晶反应、及时消耗掉锂枝晶、减缓甚至避免锂枝晶进一步生长的效果，进而可以进一步降低电池内部短路的概率，并延长电池的循环寿命。
在一些实施例中，第一涂层还可包括第一粘结剂。本申请对第一粘结剂的种类没有特别的限制，作为示例，第一粘结剂可包括但不限于偏氟乙烯均聚物(PVDF)和/或共聚物、羧甲基纤维素钠、丁苯橡胶中的一种或多种。
在一些实施例中，第一颗粒与第一粘结剂的质量比可为100:(1-25)，可选为100:(5-22)。适量的第一粘结剂可以提升第一涂层的耐热性和均一性，并可以有效避免出现如掉粉等问题，还有利于隔离膜具有良好的离子导通能力。
在一些实施例中，第一涂层还可包括第一分散剂。本申请对第一分散剂的种类没有特别的限制，作为示例，第一分散剂可包括但不限于水解聚马来酸酐、聚丙烯酸、丙烯酸嵌段共聚物、聚酯嵌段共聚物、聚乙二醇型多元醇、聚乙烯亚胺、及其各自的衍生物中的一种或多种。衍生物通常指在聚合物中的氢原子或原子团被其他原子或原子团取代而衍生的产物。
在一些实施例中，第一颗粒与第一分散剂的质量比可为100:(1.0-3.5)，可选为100:(1.2-2.5)。适量的第一分散剂可以使得浆料分散均匀，有利于涂布，还有利于提升第一涂层的膜层质量。
在一些实施例中，第一涂层还可包括第一增稠剂。本申请对第一增稠剂的种类没有特别的限制，作为示例，第一增稠剂可包括但不限于羟甲基纤维素钠、甲基纤维素、羟乙基纤维素、羟丙基甲基纤维素、聚丙烯酸盐、聚氨酯、聚醚中的一种或多种。
在一些实施例中，第一颗粒与第一增稠剂的质量比可为100:(10-30)，可选为100:(12-26)。适量的第一增稠剂可以提升浆料的稳定性，有利于涂布，还有利于提升第一涂层的膜层质量。
在一些实施例中，第一涂层的厚度可为1-7μm，可选为1.5-6μm。第一涂层的厚度在上述范围内时，有助于在隔离膜表面形成致密且均匀的中间层，更好地起到促进锂离子传输、均匀锂离子流的效果，由此可以更好地诱导锂均匀的沉积，减缓甚至抑制锂枝晶的生长，并可以有效减少局部生成尖锐的锂枝晶，进而可以减少甚至避免由于锂枝晶刺破隔离膜而出现电池内部短路的问题。此外，第一涂层的厚度在上述范围内时，隔离膜可具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在一些实施例中，第一涂层的面密度可为9-12g/m2，可选为10-11.5g/m2。第一涂层的面密度在上述范围内时，有助于在隔离膜表面形成致密且均匀的中间层，更好地起到促进锂离子传输、均匀锂离子流的效果，由此可以更好地诱导锂均匀的沉积，减缓甚至抑制锂枝晶的生长，并可以有效减少局部生成尖锐的锂枝晶，进而可以减少甚至避免由于锂枝晶刺破隔离膜而出现电池内部短路的问题。此外，第一涂层的面密度在上述范围内时，隔离膜可具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在一些实施例中，第二涂层还可包括第二粘结剂。本申请对第二粘结剂的种类没有特别的限制，作为示例，第二粘结剂可包括但不限于偏氟乙烯均聚物和/或共聚物、羧甲基纤维素钠、丁苯橡胶中的一种或多种。
在一些实施例中，第二颗粒与第二粘结剂的质量比可为100:(1-25)，可选为100:(8-22)。适量的第二粘结剂可以提升第二涂层的耐热性和均一性，并可以有效避免出现如掉粉等问题，还有利于隔离膜具有良好的离子导通能力。
在一些实施例中，第二涂层还可包括第二分散剂。本申请对第二分散剂的种类没有特别的限制，作为示例，第二分散剂可包括但不限于水解聚马来酸酐、聚丙烯酸、丙烯酸嵌段共聚物、聚酯嵌段共聚物、聚乙二醇型多元醇、聚乙烯亚胺、及其各自的衍生物中的一种或多种。衍生物通常指在聚合物中的氢原子或原子团被其他原子或原子团取代而衍生的产物。
在一些实施例中，第二颗粒与第二分散剂的质量比可为100:(0.5-4.0)，可选为100:(1.0-2.0)。适量的第二分散剂可以使得浆料分散均匀，有利于涂布，还有利于提升第二涂层的膜层质量。
在一些实施例中，第二涂层还可包括第二增稠剂。本申请对第二增稠剂的种类没有特别的限制，作为示例，第二增稠剂可包括但不限于羟甲基纤维素钠、甲基纤维素、羟乙基纤维素、羟丙基甲基纤维素、聚丙烯酸盐、聚氨酯、聚醚中的一种或多种。
在一些实施例中，第二颗粒与第二增稠剂的质量比可为100:(5-30)，可选为100：(10-25)。适量的第二增稠剂可以提升浆料的稳定性，有利于涂布，还有利于提升第二涂层的膜层质量。
在一些实施例中，第二涂层的厚度可为1-7μm，可选为1.5-6μm。第二涂层的厚度在上述范围内时，可以使第二涂层更好地起到与锂枝晶反应、及时消耗掉锂枝晶以及避免锂枝晶进一步生长的效果，由此可以有效减少甚至避免锂枝晶接触正极而出现电池内部短路的问题。此外，第二涂层的厚度在上述范围内时，隔离膜可具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在一些实施例中，第二涂层的面密度可为4-14g/m2，可选为8-12g/m2。第二涂层的面密度在上述范围内时，可以使第二涂层更好地起到与锂枝晶反应、及时消耗掉锂枝晶以及避免锂枝晶进一步生长的效果，由此可以有效减少甚至避免锂枝晶接触正极而出现电池内部短路的问题。此外，第二涂层的面密度在上述范围内时，隔离膜可具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，由此可以使电池兼具良好的循环性能和动力学性能。
在一些实施例中，多孔基材的厚度可为4-15μm，可选为5-10μm。
在一些实施例中，多孔基材可包括但不限于聚烯烃(例如聚乙烯、聚丙烯等)、卤代聚烯烃(例如聚四氟乙烯、聚偏氟乙烯、聚氯乙烯等)、聚酰胺、聚酯(例如聚对苯二甲酸乙二醇酯等)、及其各自的衍生物中的一种或多种。
衍生物通常指聚合物中的氢原子或原子团被其他原子或原子团取代而衍生的产物。
在一些实施例中，多孔基材的重均分子量可为100000-1000000。
多孔基材的重均分子量具有本领域公知的含义，可以采用本领域已知的方法进行测量。例如，可通过凝胶渗透色谱法(GPC)进行测试。
在一些实施例中，隔离膜的总厚度可为8-25μm，可选为8-18μm。由此可以使隔离膜具有较低的内阻、较短的锂离子传输路径和较高的锂离子传输速率，从而可以使电池兼具良好的循环性能和动力学性能。
在一些实施例中，隔离膜的孔隙率可为40％-80％，可选为45％-70％。由此有助于隔离膜具有良好的透气性和较高的离子传输能力。
隔离膜的孔隙率具有本领域公知的含义，可以采用本领域已知的方法进行测量。例如，可参照标准GB/T 36363-2018进行测试。
在一些实施例中，隔离膜的横向(TD)拉伸强度可为1000-1500kgf/cm2，可选为1100-1300kgf/cm2。由此可以提升电池的可靠性。
隔离膜的横向拉伸强度具有本领域公知的含义，可以采用本领域已知的方法进行测量。例如，可参照标准GB/T 36363-2018进行测试。测试时，拉伸速率可为50mm/min。
在一些实施例中，隔离膜的第一涂层与多孔基材的剥离强度可为8.9-13.2N/m，可选为9.1-11.8N/m。
在一些实施例中，隔离膜的第二涂层与多孔基材的剥离强度可为12.9-20.6N/m，可选为13.5-17.8N/m。
隔离膜具有高剥离强度，由此可以提升电池的可靠性。
隔离膜的剥离强度具有本领域公知的含义，可以采用本领域已知的方法进行测量。例如，可参照标准GB/T 36363-2018进行测试。
在一些实施例中，隔离膜的穿刺强度可为9.60-11.50N·μm-1，可选为9.80-10.90N·μm-1。由此可以提升电池的可靠性。
隔离膜的穿刺强度具有本领域公知的含义，可以采用本领域已知的方法进行测量。例如，可参照标准GB/T 36363-2018进行测试。
在一些实施例中，隔离膜25℃的离子电导率可为1.40-2.50mS·cm-1，可选为1.60-2.15mS·cm-1。由此可以提升电池的循环性能和动力学性能。
隔离膜的离子电导率可通过电化学阻抗谱实验测试得到。例如，可将隔离膜裁成一定面积的圆片，烘干后，置于两个不锈钢电极之间，待吸收足够量的电解液后密封形成扣式电池，进行电化学阻抗谱实验。使用限域性对称电池电化学阻抗谱法测得不同隔离膜层数n的电阻Rs作为隔离膜电阻，以Rs和n作图得到斜率k(对应单层隔离膜的电阻)，根据单层隔离膜的电阻、隔离膜的面积、隔离膜的厚度(单层厚度)，计算得到隔离膜的离子电导率。
颗粒的体积分布粒径Dv50为本领域公知的含义，可采用本领域已知的仪器及方法进行测定。例如可以参照GB/T 19077-2016，采用激光粒度分析仪(例如Master Size 3000)进行测试。
[隔离膜的制备方法]
本申请的实施例还提供一种隔离膜的制备方法。
制备方法包括如下步骤：提供多孔基材；提供第一涂层浆料和第二涂层浆料，第一涂层浆料包括第一颗粒，第一颗粒包括固态电解质，且干燥后的第一涂层中的第一颗粒的含量大于50重量％，第二涂层浆料包括第二颗粒，第二颗粒包括能与锂枝晶反应的无机颗粒，且干燥后的第二涂层中的第二颗粒的含量大于50重量％；将第一涂层浆料和第二涂层浆料分别涂布在多孔基材的两个表面上，干燥后，获得隔离膜。
在一些实施例中，第一涂层浆料还可包括第三颗粒。
在一些实施例中，第一涂层浆料还可包括第一粘结剂、第一分散剂和第一增稠剂中的一种或多种。
在一些实施例中，提供第一涂层浆料的步骤可包括如下步骤：将第一颗粒、第一分散剂、可选的第三颗粒加入到第一溶剂中进行一次分散，得到一次分散溶液；向所得一次分散溶液中加入第一增稠剂进行二次分散，得到二次分散溶液；向所得二次分散溶液中加入第一粘结剂搅拌均匀，得到第一涂层浆料。
可选地，提供第一涂层浆料的步骤中，第一溶剂可以包括去离子水、N,N-二甲基甲酰胺(DMF)、N-甲基吡咯烷酮(NMP)、N,N-二甲基乙酰胺(DMAC)、四氢呋喃(THF)中的一种或多种。
可选地，提供第一涂层浆料的步骤中，一次分散工艺可为超声分散。可选地，超声分散的时间在2h以上。
可选地，提供第一涂层浆料的步骤中，二次分散过程中需要进行搅拌。例如，搅拌转速可为500-1200rpm，搅拌时间可为0.5-1.5h。
可选地，提供第一涂层浆料的步骤中，向所得二次分散溶液中加入第一粘结剂后， 可以500-1200rpm的转速搅拌时间0.5-1.5h。
在一些实施例中，第一涂层浆料的固含量可为30％-50％，可选为34％-45％。由此有利于涂布。
在一些实施例中，第二涂层浆料还可包括第二粘结剂、第二分散剂和第二增稠剂中的一种或多种。
在一些实施例中，提供第二涂层浆料的步骤可包括如下步骤：将第二颗粒、第二分散剂加入到第二溶剂中进行一次分散，得到一次分散溶液；向所得一次分散溶液中加入第二增稠剂进行二次分散，得到二次分散溶液；向所得二次分散溶液中加入第二粘结剂搅拌均匀，得到第二涂层浆料。
可选地，提供第二涂层浆料的步骤中，第二溶剂可以包括去离子水、N,N-二甲基甲酰胺(DMF)、N-甲基吡咯烷酮(NMP)、N,N-二甲基乙酰胺(DMAC)、四氢呋喃(THF)中的一种或多种。
可选地，提供第二涂层浆料的步骤中，一次分散工艺可为超声分散。可选地，超声分散的时间在2h以上。
可选地，提供第二涂层浆料的步骤中，二次分散过程中需要进行搅拌。例如，搅拌转速可为500-1200rpm，搅拌时间可为0.5-1.5h。
可选地，提供第二涂层浆料的步骤中，向所得二次分散溶液中加入第二粘结剂后可以500-1200rpm的转速搅拌0.5-1.5h。
在一些实施例中，第二涂层浆料的固含量为30％-50％，可选为34％-45％。由此有利于涂布。
在一些实施例中，将第一涂层浆料和第二涂层浆料分别涂布在多孔基材的两个表面上进行干燥时，干燥温度可为60-120℃。
在一些实施例中，第一涂层浆料和第二涂层浆料的涂布方式可以采用转移涂布、旋转喷涂、浸涂、线棒刮涂等，本申请实施例对此并不限定。
本申请的实施例提供的隔离膜的制备方法中使用的一些原料及其含量等参数可以参考本申请实施方式第一方面的隔离膜，此处不再赘述。
如果没有特别的说明，在本申请的实施例提供的隔离膜的制备方法中所使用的各原料均可以通过商购获得。
[正极极片]
正极极片的结构和组成可根据电池单体的种类进行选择，本申请的实施例对此并不限定。
在一些实施例中，正极极片包括正极集流体以及设置在正极集流体至少一个表面且包括正极活性材料的正极膜层。例如，正极集流体具有在自身厚度方向相对的两个表面，正极膜层设置在正极集流体的两个相对表面中的任意一者或两者上。
正极活性材料包括能够脱出和嵌入锂离子的材料，例如，正极活性材料可包括但不限于锂过渡金属氧化物、含锂磷酸盐、层状结构的金属硫族化物、及其各自的改性化合物中的一种或多种。锂过渡金属氧化物的示例可包括但不限于锂钴氧化物、锂镍氧化物、锂锰氧化物、锂镍钴氧化物、锂锰钴氧化物、锂镍锰氧化物、锂镍钴锰氧化物、锂镍钴铝氧化物、锂钛氧化物、及其各自的改性化合物中的一种或多种。含锂磷酸盐的示例可 包括但不限于磷酸铁锂、磷酸铁锂与碳的复合材料、磷酸锰锂、磷酸锰锂与碳的复合材料、磷酸锰铁锂、磷酸锰铁锂与碳的复合材料、及其各自的改性化合物中的一种或多种。
在一些实施例中，为了进一步提升电池的能量密度，正极活性材料可以包括通式为LiaNibCocMdOeDf的锂过渡金属氧化物及其改性化合物中的一种或多种。0.8≤a≤1.2，0.5≤b＜1，0＜c＜1，0＜d＜1，1≤e≤2，0≤f≤1，M包括Ge、Mo、Sn、Mn、Al、Zr、Zn、Cu、Cr、Mg、Fe、V、Ti和B中的一种或多种，D包括N、F、S和Cl中的一种或多种。
作为示例，正极活性材料可包括LiCoO2、LiNiO2、LiMnO2、LiMn2O4、LiNi1/2Mn1/2O2、LiNi1/3Co1/3Mn1/3O2(NCM333)、LiNi0.5Co0.2Mn0.3O2(NCM523)、LiNi0.6Co0.2Mn0.2O2(NCM622)、LiNi0.8Co0.1Mn0.1O2(NCM811)、LiNi0.85Co0.15Al0.05O2、LiFePO4、LiMnPO4、Li1.13Ti0.57Fe0.3S2中的一种或多种。
上述各正极活性材料的改性化合物可以是对正极活性材料进行掺杂改性和/或表面包覆改性。
在一些实施例中，正极膜层还可选地包括正极导电剂。本申请对正极导电剂的种类没有特别的限制，作为示例，正极导电剂包括超导碳、导电石墨、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯和碳纳米纤维中的一种或多种。
在一些实施例中，正极膜层还可选地包括正极粘结剂。本申请对正极粘结剂的种类没有特别的限制，作为示例，正极粘结剂可包括聚偏氟乙烯(PVDF)、聚四氟乙烯(PTFE)、偏氟乙烯-四氟乙烯-丙烯三元共聚物、偏氟乙烯-六氟丙烯-四氟乙烯三元共聚物、四氟乙烯-六氟丙烯共聚物、含氟丙烯酸酯类树脂、聚环氧乙烷中的一种或多种。
在一些实施例中，正极集流体可采用金属箔片或复合集流体。作为金属箔片的示例，可采用铝箔。复合集流体可包括高分子材料基层以及形成于高分子材料基层至少一个表面上的金属材料层。作为示例，金属材料可包括铝、铝合金、镍、镍合金、钛、钛合金、银和银合金中的一种或多种。作为示例，高分子材料基层可包括聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)和聚乙烯(PE)中的一种或多种。
正极膜层通常是将正极浆料涂布于正极集流体上，经干燥、冷压而成的。正极浆料通常是将正极活性材料、可选的导电剂、可选的粘结剂以及任意的其他组分分散于溶剂中并搅拌均匀而形成的。溶剂可以是N-甲基吡咯烷酮(NMP)，但不限于此。
[负极极片]
负极极片的结构和组成可根据电池单体的种类进行选择，本申请的实施例对此并不限定。
在一些实施例中，负极极片可包括负极集流体以及设置在负极集流体至少一个表面上的负极膜层，负极膜层包括负极活性材料，负极活性材料包括能够脱出和嵌入活性离子的材料。例如，负极集流体具有在自身厚度方向相对的两个表面，负极膜层设置在负极集流体的两个相对表面中的任意一者或两者上。
负极活性材料可采用本领域公知的负极活性材料。作为示例，负极活性材料可包括但不限于碳基材料、硅基材料、锡基材料和钛酸锂中的一种或多种。碳基材料可包括天然石墨、人造石墨、软碳、硬碳、热解碳、焦炭、玻璃状碳、有机高分子化合物的烧成体、中间相碳微珠中的一种或多种。硅基材料可包括单质硅、硅氧化物、硅碳复合物、 硅氮复合物和硅合金材料中的一种或多种。锡基材料可包括单质锡、锡氧化物和锡合金材料中的一种或多种。
在一些实施例中，负极膜层还可选地包括负极导电剂。本申请对负极导电剂的种类没有特别的限制，作为示例，负极导电剂可包括超导碳、导电石墨、乙炔黑、炭黑、科琴黑、碳点、碳纳米管、石墨烯和碳纳米纤维中的一种或多种。
在一些实施例中，负极膜层还可选地包括负极粘结剂。本申请对负极粘结剂的种类没有特别的限制，作为示例，负极粘结剂可包括丁苯橡胶(SBR)、水溶性不饱和树脂SR-1B、水性丙烯酸类树脂(例如，聚丙烯酸PAA、聚甲基丙烯酸PMAA、聚丙烯酸钠PAAS)、聚丙烯酰胺(PAM)、聚乙烯醇(PVA)、海藻酸钠(SA)和羧甲基壳聚糖(CMCS)中的一种或多种。
在一些实施例中，负极膜层还可选地包括其他助剂。作为示例，其他助剂可包括增稠剂，例如，羧甲基纤维素钠(CMC)、PTC热敏电阻材料等。
在一些实施例中，负极集流体可采用金属箔片或复合集流体。作为金属箔片的示例，可采用铜箔。复合集流体可包括高分子材料基层以及形成于高分子材料基层至少一个表面上的金属材料层。作为示例，金属材料可包括铜、铜合金、镍、镍合金、钛、钛合金、银和银合金中的一种或多种。作为示例，高分子材料基层可包括聚丙烯(PP)、聚对苯二甲酸乙二醇酯(PET)、聚对苯二甲酸丁二醇酯(PBT)、聚苯乙烯(PS)和聚乙烯(PE)中的一种或多种。
负极膜层通常是将负极浆料涂布于负极集流体上，经干燥、冷压而成的。负极浆料通常是将负极活性材料、可选的导电剂、可选地粘结剂、其他可选的助剂分散于溶剂中并搅拌均匀而形成的。溶剂可以是N-甲基吡咯烷酮(NMP)或去离子水，但不限于此。
负极极片并不排除除了负极膜层之外的其他附加功能层。例如，在一些实施例中，负极极片还包括夹在负极集流体和负极膜层之间、设置在负极集流体表面的导电底涂层(例如由导电剂和粘结剂组成)。在一些实施例中，负极极片还包括覆盖在负极膜层表面的保护层。
在一些实施例中，负极极片还可不包括能够脱出和嵌入活性离子的材料，如石墨等。例如，在一些实施例中，负极极片可包括锂片或锂合金片；在另一些实施例中，负极极片包括网状或泡沫状三维骨架层，例如，泡沫铜(或铜合金)、泡沫镍(或镍合金)、铜(或铜合金)网、镍(或镍合金)网等。
[电解液]
电解液包括电解质盐和溶剂。电解质盐和溶剂的种类不受具体的限制，可根据实际需求进行选择。
作为示例，电解质盐可包括但不限于六氟磷酸锂(LiPF6)、四氟硼酸锂(LiBF4)、高氯酸锂(LiClO4)、六氟砷酸锂(LiAsF6)、双氟磺酰亚胺锂(LiFSI)、双三氟甲磺酰亚胺锂(LiTFSI)、三氟甲磺酸锂(LiTFS)、二氟草酸硼酸锂(LiDFOB)、二草酸硼酸锂(LiBOB)、二氟磷酸锂(LiPO2F2)、二氟二草酸磷酸锂(LiDFOP)和四氟草酸磷酸锂(LiTFOP)中的一种或多种。
在一些实施例中，电解质盐的浓度可为0.3mol/L以上，可选为0.7mol/L以上，电解质盐的浓度进一步可为4mol/L以下，可选为2.5mol/L以下、1.7mol/L以下。
溶剂可包括酯类(例如碳酸酯、磷酸酯、羧酸酯、硫酸酯、磺酸酯等)、醚类、砜类、腈类等中的一种或多种。
例如，当电池单体为锂离子电池单体时，作为示例，溶剂可包括但不限于碳酸乙烯酯(EC)、碳酸丙烯酯(PC)、碳酸丁烯酯、碳酸甲乙酯(EMC)、碳酸二乙酯(DEC)、碳酸二甲酯(DMC)、碳酸二丙酯(DPC)、碳酸甲丙酯(MPC)、碳酸乙丙酯(EPC)、碳酸亚丁酯(BC)、氟代碳酸乙烯酯(FEC)、甲酸甲酯(MF)、乙酸甲酯(MA)、乙酸乙酯(EA)、乙酸丙酯(PA)、丙酸甲酯(MP)、丙酸乙酯(EP)、丙酸丙酯(PP)、丁酸甲酯(MB)、丁酸乙酯(EB)、1,4-丁内酯(GBL)、环丁砜(SF)、二甲砜(MSM)、甲乙砜(EMS)、二乙砜(ESE)、二甲醚四甘醇(TEGDME)、乙二醇二甲醚(DME)、1,3-二氧戊烷(DOL)、磷酸三甲酯、3-甲氧基丙腈中的一种或多种。
例如，当电池单体为锂金属电池单体、无负极锂金属电池单体时，溶剂可包括醚类溶剂和/或氟醚类溶剂，例如可以包括二甲醚四甘醇(TEGDME)、乙二醇二甲醚(DME)、1,3-二氧戊烷(DOL)、H(CF2)2OCH3、C4F9OCH3、H(CF2)2OCH2CH3、H(CF2)2OCH2CF3、H(CF2)2CH2O(CF2)2H、CF3CHFCF2OCH3、CF3CHFCF2OCH2CH3、2-三氟甲基六氟丙基甲醚、2-三氟甲基六氟丙基乙醚、2-三氟甲基六氟丙基丙醚、3-三氟甲基八氟丁基甲醚、3-三氟甲基八氟丁基乙醚、3-三氟甲基八氟丁基丙醚、4-三氟甲基十氟戊基甲醚、4-三氟甲基十氟戊基乙醚、4-三氟甲基十氟戊基丙醚、5-三氟甲基十二氟己基甲醚、5-三氟甲基十二氟己基乙醚、5-三氟甲基十二氟己基丙醚、6-三氟甲基十四氟庚基甲醚、6-三氟甲基十四氟庚基乙醚、6-三氟甲基十四氟庚基丙醚、7-三氟甲基十六氟辛基甲醚、7-三氟甲基十六氟辛基乙醚、7-三氟甲基十六氟辛基丙醚中的一种或多种。
在一些实施例中，电解液中还可选地包括添加剂。例如，添加剂可以包括负极成膜添加剂，也可以包括正极成膜添加剂，还可以包括能够改善电池某些性能的添加剂，例如改善电池过充性能的添加剂、改善电池高温性能的添加剂、改善电池低温功率性能的添加剂等。
本申请的实施例还提供一种用电装置，用电装置包括本申请的电池。电池可以用作用电装置的电源，也可以用作用电装置的能量存储单元。用电装置可以但不限于是移动设备(例如手机、笔记本电脑等)、电动车辆(例如纯电动车、混合动力电动车、插电式混合动力电动车、电动自行车、电动踏板车、电动高尔夫球车、电动卡车等)、电气列车、船舶及卫星、储能系统等。
用电装置可以根据其使用需求来选择电池的具体种类，例如可为电池单体、电池模块或电池包。
图7是作为一个示例的用电装置的示意图。该用电装置为纯电动车、混合动力电动车、或插电式混合动力电动车等。为了满足该用电装置对高功率和高能量密度的需求，可以采用电池包或电池模块作为电源。
作为另一个示例的用电装置可以是手机、平板电脑、笔记本电脑等。该用电装置通常要求轻薄化，可以采用电池单体作为电源。
安施例
下述实施例更具体地描述了本申请公开的内容，这些实施例仅仅用于阐述性说明， 因为在本申请公开内容的范围内进行各种修改和变化对本领域技术人员来说是明显的。除非另有声明，以下实施例中所报道的所有份、百分比和比值都是基于质量计，而且实施例中使用的所有试剂都可商购获得或是按照常规方法进行合成获得，并且可直接使用而无需进一步处理，以及实施例中使用的仪器均可商购获得。
实施例1-27的隔离膜均按照如下方法进行制备。
多孔基材的制备
将厚度为7μm聚乙烯多孔膜经过乙醇或丙酮清洗后、在60℃下干燥和铺平后进行等离子处理4min，获得多孔基材，备用。
第一涂层浆料的制备
将表1所示第一颗粒、第三颗粒、第一分散剂丙烯酸嵌段共聚物和第一溶剂NMP混合，在超声清洗机中超声分散2h，得到一次分散溶液。向所得一次分散溶液中加入第一增稠剂羟甲基纤维素钠进行二次分散，得到二次分散溶液，搅拌转速为1100rpm，搅拌时间为1h。向所得二次分散溶液中加入第一粘结剂PVDF，以900rpm搅拌60min，结束后得到第一涂层浆料。实施例1-27中，第一颗粒、第三颗粒、第一粘结剂、第一增稠剂、第一分散剂的质量比如表1所示。表1中，Li1.3Al0.3Ti1.7(PO4)3简写为LATP，LiTi2(PO4)3简写为LTP，Li7La3Zr2O12简写为LLZO。
第二涂层浆料的制备
将表1所示第二颗粒、第二分散剂丙烯酸嵌段共聚物和第二溶剂NMP混合，在超声清洗机中超声分散2h，得到一次分散溶液。向所得一次分散溶液中加入第二增稠剂羟甲基纤维素钠进行二次分散，得到二次分散溶液，搅拌转速为1100rpm，搅拌时间为1h。向所得二次分散溶液中加入第二粘结剂PVDF，以900rpm搅拌60min，结束后得到第二涂层浆料。实施例1-27中，第二颗粒、第二粘结剂、第二增稠剂、第二分散剂的质量比如表1所示。
隔离膜的制备
将第一涂层浆料和第二涂层浆料分别通过线棒涂布的方式涂覆在多孔基材的两侧，在60℃下真空烘干30min，得到隔离膜。实施例1-27中，第一涂层和第二涂层的厚度如表1所示。
对比例1
多孔基材的制备
将厚度为7μm聚乙烯多孔膜经过乙醇或丙酮清洗后、在60℃下干燥和铺平后进行等离子处理4min，获得多孔基材，备用。
涂层浆料的制备
将Li1.3Al0.3Ti1.7(PO4)3、分散剂丙烯酸嵌段共聚物和溶剂NMP混合，在超声清洗机中超声分散2h，得到一次分散溶液。向所得一次分散溶液中加入增稠剂羟甲基纤维素钠进行二次分散，得到二次分散溶液，搅拌转速为1100rpm，搅拌时间为1h。向所得二次分散溶液中加入粘结剂PVDF，以900rpm搅拌60min，结束后得到涂层浆料。Li1.3Al0.3Ti1.7(PO4)3、粘结剂、增稠剂、分散剂的质量比为100:25.0:2.5:30.0。
隔离膜的制备
将涂层浆料通过线棒涂布的方式涂覆在多孔基材的两侧，在60℃下真空烘干30min，得到隔离膜。位于多孔基材两侧的涂层的厚度均为4μm。
对比例2
多孔基材的制备
将厚度为7μm聚乙烯多孔膜经过乙醇或丙酮清洗后、在60℃下干燥和铺平后进行等离子处理4min，获得多孔基材，备用。
涂层浆料的制备
将SiO颗粒、分散剂丙烯酸嵌段共聚物和溶剂NMP混合，在超声清洗机中超声分散2h，得到一次分散溶液。向所得一次分散溶液中加入增稠剂羟甲基纤维素钠进行二次分散，得到二次分散溶液，搅拌转速为1100rpm，搅拌时间为1h。向所得二次分散溶液中加入粘结剂PVDF，以900rpm搅拌60min，结束后得到涂层浆料。SiO颗粒、粘结剂、增稠剂、分散剂的质量比为100:25.0:2.5:30.0。
隔离膜的制备
将涂层浆料通过线棒涂布的方式涂覆在多孔基材的两侧，在60℃下真空烘干30min，得到隔离膜。位于多孔基材两侧的涂层的厚度均为4μm。
对比例3
多孔基材的制备
将厚度为7μm聚乙烯多孔膜经过乙醇或丙酮清洗后、在60℃下干燥和铺平后进行等离子处理4min，获得多孔基材，备用。
第一涂层浆料的制备
将第一颗粒Li1.3Al0.3Ti1.7(PO4)3(体积分布粒径Dv50为0.5μm)、第一分散剂丙烯酸嵌段共聚物和第一溶剂NMP混合，在超声清洗机中超声分散2h，得到一次分散溶液。向所得一次分散溶液中加入第一增稠剂羟甲基纤维素钠进行二次分散，得到二次分散溶液，搅拌转速为1100rpm，搅拌时间为1h。向所得二次分散溶液中加入第一粘结剂PVDF，以900rpm搅拌60min，结束后得到第一涂层浆料。第一颗粒、第一粘结剂、第一增稠剂、第一分散剂的质量比为100:65:5:75。
第二涂层浆料的制备
将第二颗粒SiO(体积分布粒径Dv50为1μm)、第二分散剂丙烯酸嵌段共聚物和第二溶剂NMP混合，在超声清洗机中超声分散2h，得到一次分散溶液。向所得一次分散溶液中加入第二增稠剂羟甲基纤维素钠进行二次分散，得到二次分散溶液，搅拌转速为1100rpm，搅拌时间为1h。向所得二次分散溶液中加入第二粘结剂PVDF，以900rpm搅拌60min，结束后得到第二涂层浆料。第二颗粒、第二粘结剂、第二增稠剂、第二分散剂的质量比为100:65:5:75。
将第一涂层浆料和第二涂层浆料分别通过线棒涂布的方式涂覆在多孔基材的两侧，在60℃下真空烘干30min，得到隔离膜。第一涂层和第二涂层的厚度均为4μm。
上述实施例1-27和对比例1-3中，当隔离膜用于电池中时，第一涂层均面向负极、第二涂层均面向正极。
对比例4
隔离膜的制备方法与实施例1相同，不同之处在于，当隔离膜用于电池中时，将实施 例1制备的隔离膜的第一涂层设置成面向正极、第二涂层设置成面向负极。
性能测试
(1)隔离膜的横向拉伸强度测试
依据GB/T 36363-2018测试隔离膜横向方向的拉伸强度。将隔离膜裁切成宽度10mm、长度150mm的样品(长度方向平行于隔离膜横向方向)进行测试。测试仪器可为万能拉力机，拉伸速率可为50mm/min。测试时，隔离膜样品的数量可为6个以上，测试结果取平均值。
(2)隔离膜的穿刺强度测试
依据GB/T 36363-2018测试隔离膜的穿刺强度。将隔离膜裁切成宽度10mm、长度150mm的样品，用钢针以50mm/min的速率进行穿刺，读取钢针穿透隔离膜时的最大负荷。测试时，隔离膜样品的数量可为6个以上，每个隔离膜样品取3个点，测试结果取平均值。钢针的直径可为1mm，球形顶端半径可为0.5mm，钢针的表面光洁、无锈蚀、氧化层及油污。
(3)隔离膜的离子电导率测试
隔离膜的离子电导率通过电化学阻抗谱实验测试得到。具体地，将隔离膜裁成直径为22mm的圆片，烘干后，置于两个不锈钢电极之间，待吸收足够量的电解液后密封形成扣式电池，采用电化学工作站进行电化学阻抗谱实验。电解液的电解质盐为LiDFOB，浓度为1.2mol/L；电解液的溶剂采用碳酸乙烯酯(EC)和碳酸甲乙酯(EMC)的混合物，质量比为30:70。使用限域性对称电池电化学阻抗谱法测得不同隔离膜层数n的电阻Rs作为隔离膜电阻，以Rs和n作图得到斜率k(对应单层隔离膜的电阻)，根据单层隔离膜的电阻、隔离膜的面积、隔离膜的厚度(单层厚度)，计算得到隔离膜的离子电导率。
电化学工作站可采用上海辰华CHI 660C电化学工作站，交流信号频率范围为0.01Hz至1MHz，正弦波电位幅值为5mV。为了准确性，取6个平行样品的平均值作为测试结果。
测试结果示出在表2中。
接下来将上述隔离膜组装成扣式电池后，进行电化学性能的测试。
扣式电池可按照如下方法制备。
将磷酸铁锂、导电剂炭黑(Super P)、粘结剂聚偏氟乙烯(PVDF)按照质量比8:1:1在适量的溶剂N-甲基吡咯烷酮(NMP)中混合均匀，得到正极浆料；将正极浆料涂布于正极集流体铝箔上，干燥后，得到正极极片。在氩气保护的手套箱中，将正极极片、隔离膜、锂片组装成CR2430型扣式电池。电解液的电解质盐为LiDFOB，浓度为1.2mol/L；电解液的溶剂采用碳酸乙烯酯(EC)和碳酸甲乙酯(EMC)的混合物，质量比为30:70。
实施例1-27和对比例1-3的隔离膜的第一涂层均面向锂片，第二涂层均面向正极极片。对比例4采用与实施例1相同的隔离膜，不同之处在于将实施例1制备的隔离膜的第一涂层设置成面向正极极片、第二涂层面向锂片。
在25℃下，将扣式电池以0.1C恒流充电至3.65V，接着以3.65V恒压充电至0.02C；将扣式电池静置10min后，以0.1C恒流放电至2.5V。将扣式电池按照上述方法循环两圈后，再进行如下循环性能测试。
首先，将扣式电池以0.33C恒流充电至3.65V，接着以3.65V恒压充电至0.02C，使扣式电池满充；接着将扣式电池静置10min后，以0.33C恒流放电至2.5V，此为一个循环充放电过程，记录此时的放电容量，即为第1圈的放电容量。
将扣式电池按照上述方法循环100圈。计算扣式电池第21圈至第100圈的库伦效率的平均值，作为扣式电池的平均库伦效率。库伦效率＝放电容量/充电容量。扣式电池循环100圈后的容量保持率＝第100圈的放电容量/第20圈的放电容量。
将扣式电池按照上述方法进行循环充放电测试，记录每圈循环后的放电容量，直至扣式电池的放电容量衰减为第1圈放电容量的70％，用此时的循环圈数表征电池的循环性能。
测试结果示出在表2中。
表2

综合表1和表2可知，通过在多孔基材的两个表面上分别设置面向负极的第一涂层和面向正极的第二涂层，使第一涂层包括第一颗粒(固态电解质)，且第一涂层中的第一颗粒的含量大于50重量％，使第二涂层包括第二颗粒(能与锂枝晶反应的无机颗粒)，且第二涂层中的第二颗粒的含量大于50重量％，由此获得的隔离膜可兼具良好的机械强度和良好的离子导通能力。
综合表1和表2还可知，本申请的实施例提供的隔离膜可使电池具有良好的循环性能，并可以有效降低电池内部短路的概率。
综合表1和表2还可知，当第一涂层除包括固态电解质之外，还包括少量，例如不超过10重量％的第三颗粒(能与锂枝晶反应的无机颗粒)时，可以进一步改善电池的循环性能。
需要说明的是，本申请不限定于上述实施方式。上述实施方式仅为示例，在本申请的技术方案范围内具有与技术思想实质相同的构成、发挥相同作用效果的实施方式均包含在本申请的技术范围内。此外，在不脱离本申请主旨的范围内，对实施方式施加本领域技术人员能够想到的各种变形、将实施方式中的一部分构成要素加以组合而构筑的其他方式也包含在本申请的范围内。

Claims (20)

  1. 一种隔离膜，其中，所述隔离膜包括多孔基材以及分别位于所述多孔基材的两个表面上的第一涂层和第二涂层，用于电池时，所述第一涂层面向负极，所述第二涂层面向正极；
    所述第一涂层包括第一颗粒，所述第一颗粒包括固态电解质，且所述第一涂层中的所述第一颗粒的含量大于50重量％；
    所述第二涂层包括第二颗粒，所述第二颗粒包括能与锂枝晶反应的无机颗粒，且所述第二涂层中的所述第二颗粒的含量大于50重量％。
  2. 根据权利要求1所述的隔离膜，其中，
    所述第一涂层中的所述第一颗粒的含量大于等于60重量％，可选为大于等于65重量％，更可选为65-85重量％；和/或，
    所述第二涂层中的所述第二颗粒的含量大于等于60重量％，可选为大于等于65重量％，更可选为65-85重量％。
  3. 根据权利要求1或2所述的隔离膜，其中，所述第一涂层还包括第三颗粒；
    可选地，所述第三颗粒包括能与锂枝晶反应的无机颗粒；和/或，
    可选地，所述第一涂层中的所述第三颗粒的含量大于0且小于等于10重量％，可选为大于0且小于等于5重量％；和/或，
    可选地，所述第三颗粒的体积分布粒径Dv50为0.05-3μm，可选为0.1-1μm。
  4. 根据权利要求1-3任一项所述的隔离膜，其中，所述固态电解质包括无机固态电解质；
    可选地，所述无机固态电解质的电导率大于等于10-7S/cm，更可选为大于等于10-4S/cm。
  5. 根据权利要求4所述的隔离膜，其中，所述无机固态电解质包括氧化物型无机固态电解质、硫化物型无机固态电解质和卤化物型无机固态电解质中的一种或多种；
    可选地，所述氧化物型无机固态电解质包括NASICON型固态电解质、石榴石型固态电解质、钙钛矿型固态电解质、LISICON型固态电解质中的一种或多种；和/或，
    可选地，所述硫化物型无机固态电解质包括硫化物型晶态固态电解质和硫化物玻璃型固态电解质中的一种或多种。
  6. 根据权利要求4或5所述的隔离膜，其中，所述无机固态电解质包括磷酸钛锂(LixTiy(PO4)3，0<x<2，0<y<3)、磷酸钛铝锂(LixAlyTiz(PO4)3，LATP，0<x<2，0<y<1，0<z<3)、磷酸锗铝锂(LixAlyGez(PO4)3，LAGP，0<x<2，0<y<1，0<z<3)、磷酸锆铝锂(LixAlyZrz(PO4)3，LAZP，0<x<2，0<y<1，0<z<3)、磷酸铬铝锂(LixAlyCrz(PO4)3，LACP，0<x<2，0<y<1，0<z<3)、(LiAlTiP)xOy型玻璃(0<x<4，0<y<13)、钛酸镧锂(LixLayTiO3，0<x<2，0<y<3)、锂澜锆氧化物(Li7La3Zr2O12，LLZO)、锂澜铊氧化物(Li5La3Ta2O12，LLTA)、锂锌锗氧化物(Li14ZnGe4O16)、锂硫银锗矿电解质Li6PS5X(X包括选自Cl、Br、I中的一种或多种)、SiS2型玻璃(LixSiySz，0<x<3，0<y<2，0<z<4)、P2S5型玻璃(LixPySz，0<x<3，0<y<3，0<z<7)、Li3PS4、Li7P3S11、Li10GeP2S12、及其各自的掺杂化合物中的一种或多种；可选地包括磷酸 钛锂(LixTiy(PO4)3，0<x<2，0<y<3)、磷酸钛铝锂(LixAlyTiz(PO4)3，LATP，0<x<2，0<y<1，0<z<3)、磷酸锗铝锂(LixAlyGez(PO4)3，LAGP，0<x<2，0<y<1，0<z<3)、磷酸锆铝锂(LixAlyZrz(PO4)3，LAZP，0<x<2，0<y<1，0<z<3)、磷酸铬铝锂(LixAlyCrz(PO4)3，LACP，0<x<2，0<y<1，0<z<3)、及其各自的掺杂化合物中的一种或多种。
  7. 根据权利要求1-6任一项所述的隔离膜，其中，所述能与锂枝晶反应的无机颗粒包括无机陶瓷颗粒；
    可选地，所述无机陶瓷包括氧化铝、二氧化硅、氧化亚硅、三氧化二铁、四氧化三铁、一氧化钴、四氧化三钴、一氧化锡、二氧化锡、氧化镍、磷酸铁、氧化铜、氧化钛、氧化锆、氧化钡、氧化钙、氧化镁、氮化铝、氮化硅、氮化硼、钛酸锆、钛酸钡、及其各自的改性材料中的一种或多种，
    更可选为包括氧化铝、二氧化硅、氧化亚硅、一氧化钴、四氧化三钴、一氧化锡、二氧化锡、氧化镍、磷酸铁、氧化铜、氧化钛、及其各自的改性材料中的一种或多种。
  8. 根据权利要求1-7任一项所述的隔离膜，其中，
    所述第一颗粒的体积分布粒径Dv50为0.05-3μm，可选为0.1-1μm；和/或，
    所述第二颗粒的体积分布粒径Dv50为0.5-5μm，可选为1-3μm。
  9. 根据权利要求1-8任一项所述的隔离膜，其中，所述第一涂层还包括第一粘结剂、第一分散剂和第一增稠剂中的一种或多种；
    可选地，所述第一颗粒与所述第一粘结剂的质量比为100:(1-25)，更可选为100:(5-22)；和/或，
    可选地，所述第一颗粒与所述第一分散剂的质量比为100:(1.0-3.5)，更可选为100:(1.2-2.5)；和/或，
    可选地，所述第一颗粒与所述第一增稠剂的质量比为100:(10-30)，更可选为100:(12-26)。
  10. 根据权利要求9所述的隔离膜，其中，
    所述第一粘结剂包括偏氟乙烯均聚物和/或共聚物、羧甲基纤维素钠、丁苯橡胶中的一种或多种；和/或，
    所述第一分散剂包括水解聚马来酸酐、聚丙烯酸、丙烯酸嵌段共聚物、聚酯嵌段共聚物、聚乙二醇型多元醇、聚乙烯亚胺、及其各自的衍生物中的一种或多种；和/或，
    所述第一增稠剂包括羟甲基纤维素钠、甲基纤维素、羟乙基纤维素、羟丙基甲基纤维素、聚丙烯酸盐、聚氨酯、聚醚中的一种或多种。
  11. 根据权利要求1-10任一项所述的隔离膜，其中，所述第二涂层还包括第二粘结剂、第二分散剂和第二增稠剂中的一种或多种；
    可选地，所述第二颗粒与所述第二粘结剂的质量比为100:(1-25)，更可选为100:(8-22)；和/或，
    可选地，所述第二颗粒与所述第二分散剂的质量比为100:(0.5-4.0)，更可选为100:(1.0-2.0)；和/或，
    可选地，所述第二颗粒与所述第二增稠剂的质量比为100:(5-30)，更可选为100：(10-25)。
  12. 根据权利要求11所述的隔离膜，其中，
    所述第二粘结剂包括偏氟乙烯均聚物和/或共聚物、羧甲基纤维素钠、丁苯橡胶中的一种或多种；和/或，
    所述第二分散剂包括水解聚马来酸酐、聚丙烯酸、丙烯酸嵌段共聚物、聚酯嵌段共聚物、聚乙二醇型多元醇、聚乙烯亚胺、及其各自的衍生物中的一种或多种；和/或，
    所述第二增稠剂包括羟甲基纤维素钠、甲基纤维素、羟乙基纤维素、羟丙基甲基纤维素、聚丙烯酸盐、聚氨酯、聚醚中的一种或多种。
  13. 根据权利要求1-12任一项所述的隔离膜，其中，
    所述第一涂层的面密度为9-12g/m2，可选为10-11.5g/m2；和/或，
    所述第二涂层的面密度为4-14g/m2，可选为8-12g/m2。
  14. 根据权利要求1-13任一项所述的隔离膜，其中，所述第一涂层的厚度与所述第二涂层的厚度之比为(0.2-5):1，可选为(0.25-4):1。
  15. 根据权利要求1-14任一项所述的隔离膜，其中，
    所述第一涂层的厚度为1-7μm，可选为1.5-6μm；和/或，
    所述第二涂层的厚度为1-7μm，可选为1.5-6μm；和/或，
    所述隔离膜的总厚度为8-25μm，可选为8-18μm。
  16. 根据权利要求1-15任一项所述的隔离膜，其中，
    所述多孔基材包括聚烯烃、卤代聚烯烃、聚酰胺、聚酯、及其各自的衍生物中的一种或多种；和/或，
    所述多孔基材的厚度为4-15μm，可选为5-10μm。
  17. 根据权利要求1-16任一项所述的隔离膜，其中，所述隔离膜满足如下中的至少一者：
    (1)所述隔离膜的孔隙率为40％-80％，可选为45％-70％；
    (2)所述隔离膜的横向拉伸强度为1000-1500kgf/cm2，可选为1100-1300kgf/cm2；
    (3)所述隔离膜的第一涂层与多孔基材的剥离强度为8.9-13.2N/m，可选为9.1-11.8N/m；
    (4)所述隔离膜的第二涂层与多孔基材的剥离强度为12.9-20.6N/m，可选为13.5-17.8N/m；
    (5)所述隔离膜的穿刺强度为9.60-11.50N·μm-1，可选为9.80-10.90N·μm-1；
    (6)所述隔离膜25℃的离子电导率为1.40-2.50mS·cm-1，可选为1.60-2.15mS·cm-1。
  18. 一种电池，包括电池单体以及箱体，所述电池单体包括正极极片、负极极片以及权利要求1-17任一项所述的隔离膜，且所述隔离膜的第一涂层面向所述负极极片，所述隔离膜的第二涂层面向所述正极极片。
  19. 根据权利要求18所述的电池，其中，所述电池单体包括锂离子电池单体、锂金属电池单体、无负极锂金属电池单体、锂硫电池单体、锂空气电池单体中的至少一种。
  20. 一种用电装置，包括权利要求18或19所述的电池。
PCT/CN2023/080663 2023-03-10 2023-03-10 隔离膜、电池和用电装置 Ceased WO2024187294A1 (zh)

Priority Applications (4)

Application Number Priority Date Filing Date Title
PCT/CN2023/080663 WO2024187294A1 (zh) 2023-03-10 2023-03-10 隔离膜、电池和用电装置
EP23926655.4A EP4672475A4 (en) 2023-03-10 2023-03-10 SEPARATOR, BATTERY AND ELECTRICAL DEVICE
CN202380049983.5A CN119422280A (zh) 2023-03-10 2023-03-10 隔离膜、电池和用电装置
US19/281,782 US20250379265A1 (en) 2023-03-10 2025-07-28 Separator, battery and electric device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2023/080663 WO2024187294A1 (zh) 2023-03-10 2023-03-10 隔离膜、电池和用电装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US19/281,782 Continuation US20250379265A1 (en) 2023-03-10 2025-07-28 Separator, battery and electric device

Publications (1)

Publication Number Publication Date
WO2024187294A1 true WO2024187294A1 (zh) 2024-09-19

Family

ID=92754191

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2023/080663 Ceased WO2024187294A1 (zh) 2023-03-10 2023-03-10 隔离膜、电池和用电装置

Country Status (4)

Country Link
US (1) US20250379265A1 (zh)
EP (1) EP4672475A4 (zh)
CN (1) CN119422280A (zh)
WO (1) WO2024187294A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN119560624A (zh) * 2025-01-24 2025-03-04 深圳海辰储能科技有限公司 固态电解质颗粒及其制备方法、隔膜、电池及储能装置
WO2026123529A1 (zh) * 2024-12-09 2026-06-18 宁德时代新能源科技股份有限公司 固态电池单体、电池装置、用电装置、电解质片及其制备方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111900315A (zh) * 2020-08-04 2020-11-06 中国科学院物理研究所 具有双面涂覆材料涂层的陶瓷隔膜及其制备方法和应用
CN113363669A (zh) * 2021-06-23 2021-09-07 天津市捷威动力工业有限公司 一种复合隔膜、包含其的锂离子电池及其制备方法和应用
CN114464960A (zh) * 2022-03-14 2022-05-10 北京卫蓝新能源科技有限公司 一种锂电池复合隔膜及其制备方法和应用
CN114552129A (zh) * 2021-07-13 2022-05-27 万向一二三股份公司 一种双面差异化锂电池隔膜及含有该隔膜的锂电池

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104269508A (zh) * 2014-09-30 2015-01-07 中航锂电（洛阳）有限公司 一种复合陶瓷涂料、锂离子电池复合陶瓷隔膜及锂离子电池
US20180026302A1 (en) * 2016-07-20 2018-01-25 University Of Dayton High-performance ceramic-polymer separators for lithium batteries
CN112382793B (zh) * 2019-07-29 2023-06-27 通用汽车环球科技运作有限责任公司 硫化物浸渍的固态电池
JP7118936B2 (ja) * 2019-09-13 2022-08-16 株式会社東芝 セパレータ、電極群、二次電池、電池パック、車両及び定置用電源
CN111697187A (zh) * 2020-05-07 2020-09-22 天津力神电池股份有限公司 一种高安全复合隔膜及其制备方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111900315A (zh) * 2020-08-04 2020-11-06 中国科学院物理研究所 具有双面涂覆材料涂层的陶瓷隔膜及其制备方法和应用
CN113363669A (zh) * 2021-06-23 2021-09-07 天津市捷威动力工业有限公司 一种复合隔膜、包含其的锂离子电池及其制备方法和应用
CN114552129A (zh) * 2021-07-13 2022-05-27 万向一二三股份公司 一种双面差异化锂电池隔膜及含有该隔膜的锂电池
CN114464960A (zh) * 2022-03-14 2022-05-10 北京卫蓝新能源科技有限公司 一种锂电池复合隔膜及其制备方法和应用

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP4672475A4 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2026123529A1 (zh) * 2024-12-09 2026-06-18 宁德时代新能源科技股份有限公司 固态电池单体、电池装置、用电装置、电解质片及其制备方法
CN119560624A (zh) * 2025-01-24 2025-03-04 深圳海辰储能科技有限公司 固态电解质颗粒及其制备方法、隔膜、电池及储能装置

Also Published As

Publication number Publication date
EP4672475A1 (en) 2025-12-31
US20250379265A1 (en) 2025-12-11
CN119422280A (zh) 2025-02-11
EP4672475A4 (en) 2026-04-22

Similar Documents

Publication Publication Date Title
JP2025528455A (ja) セパレータ、その製造方法及びそれに関連する二次電池ならびに電力消費装置
JP2025526848A (ja) セパレータ、その製造方法及びそれに関連する二次電池と電力消費装置
US20250379265A1 (en) Separator, battery and electric device
JP7785202B2 (ja) セパレータ、その製造方法、並びに、それに関連する二次電池及び電力消費装置
WO2025232272A1 (zh) 电池单体、电池以及用电装置
WO2024082291A1 (zh) 锂离子电池和用电装置
WO2024082287A1 (zh) 具有改善的电解液粘度和cb值的锂离子电池和用电装置
JP2025515853A (ja) セパレータ、その製造方法及びそれに関連する二次電池、電力消費装置
CN113346140A (zh) 一种电解液及其应用
WO2025107570A1 (zh) 隔离膜及其制备方法、电池和用电设备
WO2025010592A1 (zh) 用于锂金属电池的负极极片、电极组件、锂金属电池和电子设备
WO2024174170A1 (zh) 隔离膜、二次电池及用电装置
JP2025525594A (ja) セパレータ、その製造方法及びそれに関連する二次電池と電力消費装置
CN116420259B (zh) 电解液、二次电池、电池模块、电池包和用电装置
JP2025515798A (ja) セパレータ及びその製造方法、二次電池並びに電力消費装置
KR102909161B1 (ko) 전기화학 디바이스 및 해당 전기화학 디바이스를 포함하는 전자 디바이스
WO2025077299A1 (zh) 负极极片、二次电池和用电设备
WO2025112293A1 (zh) 隔离膜及其制备方法、电池和用电装置
CN116565154B (zh) 正极活性材料、其制备方法、以及包含其的二次电池及用电装置
CN118120087A (zh) 二次电池、电池模块、电池包及用电装置
CN116417685A (zh) 电极组件及其制备方法、二次电池、电池模块、电池包及用电装置
CN116598420B (zh) 负极极片、制备方法及相应的二次电池、用电装置
CN118676358B (zh) 正极活性材料、正极极片、电池及管理方法和应用
CN115911748B (zh) 隔膜及其制备方法、二次电池和用电装置
WO2025184907A9 (zh) 电池单体、电池以及用电装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 23926655

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 202380049983.5

Country of ref document: CN

WWP Wipo information: published in national office

Ref document number: 202380049983.5

Country of ref document: CN

WWE Wipo information: entry into national phase

Ref document number: 2023926655

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2023926655

Country of ref document: EP

Effective date: 20250923

ENP Entry into the national phase

Ref document number: 2023926655

Country of ref document: EP

Effective date: 20250923

WWP Wipo information: published in national office

Ref document number: 2023926655

Country of ref document: EP