WO2017128983A1 - Matériau composite d'électrode positive pour accumulateur lithium-ion tout solide et son procédé de préparation et son application - Google Patents

Matériau composite d'électrode positive pour accumulateur lithium-ion tout solide et son procédé de préparation et son application Download PDF

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WO2017128983A1
WO2017128983A1 PCT/CN2017/071314 CN2017071314W WO2017128983A1 WO 2017128983 A1 WO2017128983 A1 WO 2017128983A1 CN 2017071314 W CN2017071314 W CN 2017071314W WO 2017128983 A1 WO2017128983 A1 WO 2017128983A1
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positive electrode
polymer electrolyte
lithium ion
ion battery
solid
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Chinese (zh)
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谢静
马永军
易观贵
宋威
郭姿珠
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BYD Co Ltd
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BYD Co Ltd
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • 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
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
    • H01M4/136—Electrodes based on inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/581—Chalcogenides or intercalation compounds thereof
    • H01M4/5815—Sulfides
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/5825—Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines
    • 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 invention belongs to the field of lithium ion batteries, and particularly relates to an all-solid lithium ion battery cathode composite material and a preparation method thereof, a cathode material, a cathode and an all-solid lithium ion battery.
  • the preparation methods of the positive electrode of the all-solid lithium ion battery are generally classified into three types, namely, a powder tablet type, a vacuum coating type, and a coating type.
  • the powder tableting type is a method in which a positive electrode active material, an inorganic solid electrolyte powder and a conductive agent are mixed in a certain ratio and then pressed under a certain pressure. During the preparation of the method, volume expansion or volume shrinkage of the positive electrode active material occurs.
  • the effect causes the solid-solid contact interface effect between the positive active material and the inorganic solid electrolyte particles to deteriorate, and the solid-solid contact interface effect has a greater influence on the performance of the entire battery when the battery is subjected to external impact; vacuum coating type
  • the positive electrode active material is directly coated on the current collector by means of sputter coating, evaporation coating, pulsed laser deposition film or ion plating film. This method requires specific equipment, is expensive, and has low efficiency, which restricts to some extent. Commercial application; the coated positive electrode sheet is obtained by uniformly mixing a positive electrode active material, an inorganic solid electrolyte, a conductive agent and a binder in a specific solvent in a specific solvent, and then coating the mixed slurry on the current collector.
  • the method requires a binder to be added during coating, and the added binder component is non-lithium Conductor, will affect the conductivity of lithium ions inside the positive electrode, thus affecting the electrochemical performance of the battery.
  • the prior art discloses that the surface of the positive electrode material is coated with LiNbO 3 , SiO 2 , Al 2 O 3 , Ni 2 S 3 , Li 3 PS 4 or the like.
  • the methods of coating with oxides such as LiNbO 3 , SiO 2 , and Al 2 O 3 include fluidized bed method, pulsed laser deposition, etc. These methods are complicated in operation, expensive in equipment, and low in ion conductivity of the coating layer.
  • an object of the present invention is to provide an all-solid lithium ion battery positive electrode composite material and a preparation method thereof, a positive electrode material, a positive electrode, and an all solid state
  • the lithium ion battery can effectively solve the problem of the solid-solid interface layer existing between the cathode material and the sulfide solid electrolyte in the prior art and the problem of low ion conductivity.
  • the present invention provides an all-solid lithium ion battery positive electrode composite material having a core-shell structure, the core including a positive electrode active material, and the shell including a polymer electrolyte and a sulfide Solid electrolyte.
  • the present invention can reduce the direct contact between the positive electrode active material and the inorganic solid electrolyte by coating the surface of the positive electrode active material with the shell layer containing the polymer electrolyte and the inorganic solid electrolyte, thereby improving the interface problem between the positive electrode and the inorganic solid electrolyte;
  • the present invention uses a shell layer containing a polymer electrolyte and an inorganic solid electrolyte to coat a cathode active material to obtain a cathode composite material.
  • the inventors have also found that the polymer electrolyte contained in the shell layer not only has good lithium ion conductivity.
  • the polymer electrolyte component also has certain elastomeric properties, which can alleviate the positive electrode active material to a certain extent.
  • the volume expansion effect during charging and discharging; on the other hand, the sulfide solid electrolyte contained in the shell layer can not only improve the ionic conductivity of the shell polymer electrolyte, but also increase the electrochemical window of the shell polymer electrolyte, so that Positive electrode composites can match high ion power
  • the inorganic solid electrolyte and the negative electrode of the battery safety is higher, long cycle life.
  • the present invention also provides a method for preparing a solid-state lithium ion battery positive electrode composite material. According to an embodiment of the present invention, the method includes:
  • a positive electrode active material added to the emulsion of the step (2), wrapping the emulsion with the positive electrode composite material, and drying to obtain a positive electrode composite material having a core-shell structure, wherein the core includes a positive electrode active material A material comprising a polymer electrolyte and a sulfide solid electrolyte.
  • an all-solid lithium ion battery positive electrode material includes a positive electrode composite material and a positive electrode conductive agent, and the positive electrode composite The material is the all-solid lithium ion battery positive electrode composite material proposed by the invention.
  • the invention further provides an all-solid-state lithium ion battery positive electrode comprising a positive electrode material as set forth in the present application, in accordance with an embodiment of the present invention.
  • the present invention also provides an all-solid-state lithium ion battery, which according to an embodiment of the present invention includes a battery case and a battery cell located in the battery case, the battery core
  • the present invention includes a positive electrode, a negative electrode, and an inorganic solid electrolyte layer between the positive electrode and the negative electrode, wherein the positive electrode is the lithium ion proposed in the present application. Sub-cell positive.
  • FIG. 1 is a schematic structural view of a positive electrode composite material of an all-solid lithium ion battery according to the present application.
  • the present invention provides an all-solid lithium ion battery positive electrode composite material, according to an embodiment of the present invention, the positive electrode composite material has a core-shell structure, the core includes a positive electrode active material, The shell includes a polymer electrolyte and a sulfide solid electrolyte.
  • the polymer electrolyte in the solid-state lithium ion battery positive electrode composite material, may be selected from the group consisting of a polyoxyethylene polymer electrolyte, a polyvinylidene fluoride polymer electrolyte, a polyacrylonitrile-based polymer electrolyte, and a poly At least one of a methyl methacrylate-based polymer electrolyte and a polyvinyl polymer electrolyte; further preferably, the polymer electrolyte is selected from the group consisting of a polyoxyethylene polymer electrolyte, a polyvinylidene fluoride polymer electrolyte, At least one of polyacrylonitrile-based polymer electrolytes.
  • the lithium ion conductivity of the shell layer can be further improved, and at the same time, the shell has good bonding properties, thereby reducing the use of the nonionic conductivity component binder during the coating process of the cathode material.
  • the polymer electrolyte component also has certain elastomeric properties, which can alleviate the volume expansion effect of the positive active material during charge and discharge to a certain extent.
  • the polymer electrolyte of the present invention is a polymer electrolyte in the conventional sense in the prior art, that is, a complex of a polymer and a lithium salt formed by a complex reaction of a polymer and a lithium salt under certain conditions.
  • a positive electrode composite material for a positive electrode of a lithium ion battery is prepared by using a shell-coated positive electrode active material containing the above polymer electrolyte and a sulfide solid electrolyte, and the prepared battery has high safety. Performance and cycle performance; after repeated tests, it was found that the polyelectrolyte not only has good bonding property, but also has good ionic conductivity. After being mixed with a sulfide solid electrolyte, it is coated on the surface of the positive electrode active material.
  • the prepared positive electrode not only has a solid-solid interface effect with the inorganic solid electrolyte, but also has a good charge and discharge capacity of the positive electrode itself.
  • the glassy state of Li 2 SP 2 S 5 is selected from the group consisting of 70Li 2 S-30P 2 S 5 , 75Li 2 S-25P 2 S 5 , 80Li 2 S- At least one of 20P 2 S 5 ;
  • the glass-ceramic state of Li 2 SP 2 S 5 is selected from the group consisting of 70Li 2 S-30P 2 S 5 , 75Li 2 S-25P 2 S 5 , 80Li 2 S- in a glass-ceramic state At least one of 20P 2 S 5 ;
  • the crystalline state of Li x ' M y' PS z' is selected from the group consisting of Li 3 PS 4 , Li 4 SnS 4 , Li 4 GeS 4 , Li 10 SnP 2 S 12 , Li 10 At least one of GeP 2 S 12 and Li 10 SiP 2 S 12 .
  • the solid-state lithium ion battery positive electrode composite material preferably has a mass ratio of the polymer electrolyte to the sulfide solid electrolyte of 1:99 to 99:1; further preferably, the polymer electrolyte The mass ratio to the sulfide solid electrolyte is 2:8 to 1:99; or the mass ratio between the polymer electrolyte and the sulfide solid electrolyte is 8:2 to 99:1; still more preferably, the polymerization The mass ratio between the electrolyte of the substance and the solid electrolyte of the sulfide is 1:9 to 1:99; or the mass ratio between the polymer electrolyte and the sulfide solid electrolyte is 9:1 to 99:1.
  • the lithium ion conductivity of the shell layer can be further improved, and the adhesion property of the shell can be improved, and the use of the nonionic conductive component binder in the coating process of the cathode material can be reduced.
  • the ionic conductivity of the shell polymer electrolyte can be further improved, and the electrochemical window of the shell polymer electrolyte can be increased, so that the obtained cathode composite material can match the inorganic solid electrolyte and the anode with high ionic conductivity.
  • the battery is safer and has a long cycle life.
  • the all-solid lithium ion battery positive electrode composite material preferably has a mass ratio of the polymer electrolyte and the sulfide solid state electrolyte to the positive electrode active material of (40 to 5): (60 to 95) ).
  • the mass ratio of the total amount of the polymer electrolyte and the sulfide solid electrolyte to the positive electrode active material is (40 to 5): (60 to 95), which not only can well relieve the interface between the positive electrode and the inorganic solid electrolyte.
  • the impact problem can also ensure the charge and discharge efficiency of the positive electrode.
  • the corresponding negative electrode in the battery may be a negative electrode conventionally used in the art, such as a graphite negative electrode, a silicon carbon negative electrode, a metal lithium negative electrode or a lithium-indium alloy negative electrode.
  • the positive electrode active material is at least one selected from the group consisting of V 2 O 5 , MnO 2 , TiS 2 , and FeS 2 .
  • the corresponding negative electrode in the battery should be an anode active material capable of extracting lithium ions, for example, lithium metal can be used.
  • the present invention also provides a method for preparing an all-solid lithium ion battery positive electrode composite. According to an embodiment of the invention, the method comprises:
  • a positive electrode active material having a core-shell structure is obtained by adding a positive electrode active material to the emulsion of the step (2), wherein the core includes a positive electrode active material, and the shell includes a polymer electrolyte and a sulfide solid electrolyte.
  • the polymer in the step (1) is selected from the group consisting of polyoxyethylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate and poly At least one of ethylene;
  • the lithium salt is selected from the group consisting of LiPF 6 , LiAsF 6 , LiClO 4 , LiBF 6 , LiN(CF 3 SO 3 ) 2 , LiCF 3 SO 3 , LiC(CF 3 SO 3 ) 2 , LiN ( At least one of C 4 F 9 SO 2 )(CF 3 SO 3 ).
  • the polymer electrolyte prepared by using the above polymer and lithium salt can further improve the lithium ion conductivity of the shell layer, and at the same time, the shell has good bonding properties, thereby reducing non-ion conductance during coating of the cathode material.
  • the use of the component binder, and the polymer electrolyte component also has certain elastomeric properties, which can alleviate the volume expansion effect of the positive electrode active material during charging and discharging to some extent.
  • the step (1) comprises dissolving the polymer and the lithium salt in an organic ratio according to a ratio of (20 to 85): (80 to 15). After the solvent is stirred and mixed for 1-48 hours, the polymer and the lithium salt can be sufficiently subjected to a complexation reaction by using the above ratio and stirring for 1 to 48 hours, thereby efficiently preparing a polymer electrolyte.
  • the step (2) includes adding a sulfide solid electrolyte to the polymer electrolyte, and stirring and mixing for 1-48 hours to obtain an emulsion. Thereby, the polymer electrolyte can be uniformly mixed with the sulfide solid electrolyte.
  • the mass of the sulfide solid electrolyte added in the step (2) satisfies the mass ratio between the polymer electrolyte and the sulfide solid electrolyte.
  • the mass ratio between the polymer electrolyte and the sulfide solid electrolyte is 2:8 to 1:99; or the mass between the polymer electrolyte and the sulfide solid electrolyte a ratio of 8:2 to 99:1; still more preferably, the mass ratio between the polymer electrolyte and the sulfide solid electrolyte is 1:9 to 1:99; or the polymer electrolyte and the sulfide solid electrolyte The mass ratio between 9:1 and 99:1.
  • the lithium ion conductivity of the shell layer can be further improved, and the adhesion property of the shell can be improved, and the use of the nonionic conductive component binder in the coating process of the cathode material can be reduced.
  • the ionic conductivity of the shell polymer electrolyte can be further increased, and the electrochemical window of the shell polymer electrolyte can be increased, so that the obtained cathode composite can match the high ion.
  • the conductivity of the inorganic solid electrolyte and the negative electrode give the battery a higher safety and a longer cycle life.
  • the present invention further provides an all-solid lithium ion battery positive electrode material, comprising a positive electrode composite material and a positive electrode conductive material, wherein the positive electrode composite material is an all-solid lithium ion battery positive electrode composite material proposed by the present invention. .
  • the lithium ion positive electrode material proposed in the present application includes the positive electrode composite material described in the present application, the core of the positive electrode composite material includes a positive electrode active material, and the shell includes a polymer electrolyte and a sulfide solid electrolyte.
  • the above positive electrode material may also optionally comprise a positive electrode binder; since the polymer electrolyte of the shell layer of the positive electrode composite material provided by the present application not only has good ionic conductivity, but also has adhesive properties, and thus is used in the positive electrode material. It may be free of a positive binder or, optionally, a very small amount of a positive binder.
  • the positive electrode binder may be used as a binder in a positive electrode of a high-voltage lithium ion battery.
  • the positive electrode binder may be selected from a fluorine-containing resin and a polyolefin compound such as polyvinylidene fluoride (PVDF) and polytetraethylene. At least one of vinyl fluoride (PTFE) and styrene-butadiene rubber (SBR); preferably, the positive electrode binder is contained in an amount of from 0 to 5%.
  • the positive electrode conductive agent is a conductive agent used in a positive electrode of a high-voltage lithium ion battery.
  • the positive electrode conductive agent may be at least one selected from the group consisting of acetylene black, carbon nanotubes, HV, and carbon black.
  • a cathode material for a lithium ion battery according to the present invention is characterized in that the content of the positive electrode conductive agent is from 0.5% to 5% based on the mass of the positive electrode composite material.
  • the positive electrode composite material of the above embodiment of the present invention is used in the positive electrode material because the polymer electrolyte of the shell layer of the positive electrode composite material itself has good bonding properties, and therefore, the positive electrode material is prepared. In the process, it is only necessary to add a small amount of the positive electrode binder after adding the non-active positive electrode binder, and the corresponding addition amount of the positive electrode conductive agent in the positive electrode material can also be reduced.
  • the present application further provides an all-solid-state lithium ion battery positive electrode comprising the all-solid lithium ion battery positive electrode material of the above embodiment of the present invention.
  • the preparation method of the positive electrode of the present invention is not particularly limited, and is a method for preparing a positive electrode which is conventional in the art, comprising mixing the positive electrode composite material, the positive electrode conductive agent and the organic solvent according to the present invention to prepare a positive electrode slurry for coating the positive electrode current collector. Drying to obtain a positive electrode; or mixing the positive electrode composite material, the positive electrode binder and the positive electrode conductive agent described in the present application with an organic solvent to prepare a positive electrode slurry coated on the positive electrode current collector to be dried to obtain a positive electrode.
  • the positive electrode of the all-solid lithium ion battery described in the present application may also adopt the following methods, including:
  • the positive electrode active material and the positive electrode conductive agent are added to the surface of the step (2), and then coated on the surface of the positive electrode current collector to be dried to obtain the positive electrode described in the present application.
  • the polymer in the step (1) is at least one selected from the group consisting of polyoxyethylene, polyvinylidene fluoride, polyacrylonitrile, polymethyl methacrylate and polyethylene;
  • the lithium salt is selected from the group consisting of LiPF 6 , At least one of LiAsF 6 , LiClO 4 , LiBF 6 , LiN(CF 3 SO 3 ) 2 , LiCF 3 SO 3 , LiC(CF 3 SO 3 ) 2 , LiN(C 4 F 9 SO 2 )(CF 3 SO 3 ) One type;
  • the step (1) comprises dissolving the polymer and the lithium salt in an organic solvent according to a ratio of (20-85): (80-15), and stirring and mixing for 1-48 hours.
  • the polymer and the lithium salt are generated.
  • the complexation reaction results in a polymer electrolyte;
  • the step (2) comprises adding a sulfide solid electrolyte to the step (1), and stirring and mixing for 1-48 hours to obtain an emulsion;
  • the positive electrode conductive agent is well known to those skilled in the art.
  • the conductive agent in the positive electrode of the high-voltage lithium ion battery, wherein the positive electrode conductive agent may be at least one selected from the group consisting of acetylene black, carbon nanotubes, HV, and carbon black.
  • the mass of the sulfide solid electrolyte added in the step (2) satisfies the mass ratio between the polymer electrolyte and the sulfide solid electrolyte.
  • the mass ratio between the polymer electrolyte and the sulfide solid electrolyte is 2:8 to 1:99; or the mass between the polymer electrolyte and the sulfide solid electrolyte a ratio of 8:2 to 99:1; still more preferably, the mass ratio between the polymer electrolyte and the sulfide solid electrolyte is 1:9 to 1:99; or the polymer electrolyte and the sulfide solid electrolyte The mass ratio between 9:1 and 99:1.
  • the quality of the added positive electrode conductive agent satisfies: adding in step (3) based on the total mass of the obtained positive electrode material.
  • the content of the positive electrode conductive agent is from 1% to 5%.
  • the cathode current collector is a cathode current collector well known to those skilled in the art, and for example, may be selected from aluminum foil, carbon paper, carbon nanotube paper, graphene paper or stainless steel foil.
  • the present invention further provides an all-solid-state lithium ion battery comprising a battery case and a battery cell located in the battery case, the battery core including a positive electrode, a negative electrode, and a positive electrode and a negative electrode
  • an inorganic solid electrolyte layer which is the positive electrode proposed in the present application.
  • the inorganic solid electrolyte layer includes an inorganic solid electrolyte and a binder; the present invention has no special requirements on the inorganic solid electrolyte and the binder in the inorganic solid electrolyte layer, and the inorganic solid electrolyte and the binder which are conventional in the art can be used.
  • the binder is selected from at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), and styrene butadiene rubber (SBR).
  • PVDF polyvinylidene fluoride
  • PTFE polytetrafluoroethylene
  • SBR styrene butadiene rubber
  • Negative electrode such as stone A negative electrode, a negative electrode silicon carbon, lithium metal or a lithium anode - the negative electrode can be indium alloy; Specifically, the negative electrode includes a negative current collector and a negative electrode material in said negative electrode current collector surface.
  • the negative current collector is a negative current collector known to those skilled in the art, for example, may be selected from copper foil.
  • the negative electrode material includes a negative electrode active material and a negative electrode binder;
  • the negative electrode active material may be a negative electrode active material conventional in the art; specifically, the negative electrode active material is selected from the group consisting of carbon materials, tin alloys, silicon alloys, silicon, At least one of tin and antimony; further, the carbon material may be selected from the group consisting of natural graphite, naturally modified graphite, artificial graphite, petroleum coke, organic cracked carbon, mesocarbon microbeads, carbon fiber, tin alloy, and silicon alloy.
  • the negative electrode active material may also be metal lithium, lithium-indium alloy or the like; generally, the negative electrode material may further contain a negative electrode conductive agent according to actual use.
  • the negative electrode conductive agent is not particularly limited and may be a conventional negative electrode conductive agent in the art, and may be, for example, at least one of carbon black, acetylene black, furnace black, carbon fiber VGCF, conductive carbon black, and conductive graphite;
  • the fourth binder is a binder known in the art for use in a negative electrode of a lithium ion battery. Specifically, the fourth binder may be selected from the group consisting of polythiophene and poly.
  • Oxide polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, polystyrene, polyacrylamide, ethylene-propylene-diene copolymer resin, styrene butadiene rubber, polybutadiene, fluororubber, Polyethylene oxide, polyvinylpyrrolidone, polyester resin, acrylic resin, phenolic resin, epoxy resin, polyvinyl alcohol, carboxypropyl cellulose, ethyl cellulose, sodium carboxymethyl cellulose, styrene-butadiene latex At least one.
  • the content of the negative electrode active material and the negative electrode binder in the above negative electrode material is known to those skilled in the art, and specifically, the content of the negative electrode conductive agent is 0.5 to 10% by weight based on the weight of the negative electrode active material; The content of the negative electrode binder is 0.01 to 10% by weight.
  • the positive electrode active material is selected from at least one of V 2 O 5 , MnO 2 , TiS 2 , and FeS 2 ;
  • the negative electrode of lithium ion for example, lithium pre-calined graphite or a silicon negative electrode may be used, or metal lithium, lithium-indium alloy or the like may be used as it is; preferably, the corresponding negative electrode is metal lithium, lithium-indium alloy or the like.
  • the preparation method of the negative electrode of the battery in the present invention is not particularly limited, and the preparation method of the negative electrode conventional in the art may be used.
  • the negative electrode slurry containing the negative electrode active and negative electrode binder is coated on the negative electrode current collector.
  • a negative electrode material layer is formed on the negative electrode current collector.
  • the specific preparation method of lithium ion in the present invention is not particularly limited, and is a preparation method of an all-solid lithium ion battery which is conventional in the art; and the battery core is sealed in a battery case; the preparation of the battery core is conventional in the art.
  • the preparation method of the electric core in the all-solid lithium ion battery is not particularly limited; the preparation of the positive electrode is first prepared, and then the solid electrolyte layer is prepared on the surface of the positive electrode.
  • the solid electrolyte layer in the present application is an inorganic solid electrolyte layer;
  • the method of injecting an inorganic solid electrolyte layer comprises: drying an inorganic solid electrolyte slurry on a surface of the positive electrode to form an inorganic solid electrolyte layer on the surface of the positive electrode; the inorganic solid electrolyte slurry comprising an inorganic solid electrolyte and a binder;
  • the inorganic solid electrolyte is preferably a sulfide solid electrolyte; the kind of the binder and the ratio of the inorganic solid electrolyte to the binder are well known to those skilled in the art, and are not specifically limited herein.
  • the negative electrode is laminated on the solid electrolyte layer to obtain a lithium ion battery of the present application.
  • the positive electrode and the solid electrolyte are bonded together to obtain a lithium ion battery according to the present application.
  • the lithium ion battery provided by the present application adopts the positive electrode active material described in the present application, and the positive electrode has high ionic conductivity, and the interface between the positive electrode and the inorganic solid electrolyte layer has little influence, and the prepared battery has high safety. Good cycle performance.
  • step (1) (2) adding 750.0 g of LiNi 0.5 Mn 1.5 O 4 and 10.0 g of carbon nanotubes to the emulsion of step (1), and continuing magnetic stirring for 2 h, after forming a stable and uniform positive electrode slurry, coating on the aluminum foil current collector, and then After drying at 80 ° C, the positive electrode sheet A1 was obtained after being pressed by a roll press.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that the glassy sulfide solid electrolyte 75Li 2 S-25P 2 S 5 was not added in the step (1); And an all-solid-state lithium-ion battery DS1.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that the lithium salt LiN(CF 3 SO 3 ) 2 was not added in the step (1); the positive electrode sheet DA2 and the all solid lithium were prepared. Ion battery DS2.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that step (1) used 7.0 g of polyvinylidene fluoride instead of polyoxyethylene, acetone was used instead of acetonitrile, and step (3) was added. 490.0 g of a glassy sulfide solid electrolyte 75Li 2 S-25P 2 S 5 ; A positive electrode sheet A3 and an all-solid lithium ion battery S3 were prepared.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that step (1) used 7.0 g of polyacrylonitrile instead of polyoxyethylene, acetone was used instead of acetonitrile, and step (3) used 490.0.
  • step (1) used 7.0 g of polyacrylonitrile instead of polyoxyethylene
  • acetone was used instead of acetonitrile
  • step (3) used 490.0.
  • g Crystalline sulfide solid electrolyte Li 3 PS 4 replaces glassy sulfide solid electrolyte 75Li 2 S-25P 2 S 5 ;
  • a positive electrode sheet A4 and an all-solid lithium ion battery S4 were prepared.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that step (1) used 7.0 g of polymethyl methacrylate instead of polyoxyethylene, and acetone was used instead of acetonitrile.
  • Step (3) A 228.0 g crystalline sulfide solid electrolyte Li 4 SnS 4 was used in place of the glassy sulfide solid electrolyte 75Li 2 S-25P 2 S 5 ; a positive electrode sheet A5 and an all-solid lithium ion battery S5 were prepared.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that step (1) used 7.0 g of polyethylene instead of polyoxyethylene and 5.0 g of LiPF 6 instead of LiN (CF 3 SO 3 ). 2 ; A positive electrode sheet A6 and an all-solid lithium ion battery S6 were prepared.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that 750.0 g of LiFePO 4 was used in place of LiNi 0.5 Mn 1.5 O 4 in the step (2); the positive electrode sheet A7 and the all solid lithium were prepared. Ion battery S7.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 7, except that the sulfide solid electrolyte Li 2 SP 2 S 5 was not added in the step (1); the positive electrode sheet DA3 and the all solid lithium were prepared. Ion battery DS3.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 7, except that the lithium salt LiN(CF 3 SO 3 ) 2 was not added in the step (1); the positive electrode sheet DA4 and the all solid lithium were prepared. Ion battery DS4.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that 750.0 g of LiCoO 2 was used in place of LiNi 0.5 Mn 1.5 O 4 in the step (2); the positive electrode sheet A8 and the all solid lithium were prepared. Ion battery S8.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 8, except that the sulfide solid electrolyte Li 2 SP 2 S 5 was not added in the step (1); the positive electrode sheet DA5 and the all solid lithium were prepared. Ion battery DS5.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 8, except that the lithium salt LiN(CF 3 SO 3 ) 2 was not added in the step (1); the positive electrode sheet DA6 and the all solid lithium were prepared. Ion battery DS6.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that 750.0 g of V 2 O 5 was used in place of LiNi 0.5 Mn 1.5 O 4 in the step (2); the positive electrode sheet A9 and the whole were prepared.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 9, except that the sulfide solid electrolyte Li 2 SP 2 S 5 was not added in the step (1); the positive electrode sheet DA7 and the all solid lithium were prepared. Ion battery DS7.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 9, except that the lithium salt LiN(CF 3 SO 3 ) 2 was not added in the step (1); the positive electrode sheet DA8 and the all solid lithium were prepared. Ion battery DS8.
  • a positive electrode sheet and an all-solid lithium ion battery were prepared in the same manner as in Example 1, except that 750.0 g of TiS 2 was used in place of LiNi 0.5 Mn 1.5 O 4 in the step (2); the positive electrode sheet A10 and the all solid lithium were prepared. Ion battery S10.
  • the frequency range is 100KHz-0.1Hz, the amplitude is 50mV; the impedance of all solid-state lithium-ion batteries S1-S10 and DS1-DS8 before charging and discharging is tested.
  • the test results are shown in Table 1;
  • the specific test conditions are: charging the batteries S1-S10 and DS1-DS8 constant current 0.01C to a certain voltage cut-off at 25 ⁇ 1°C (the cut-off voltage of the S1-S6 and DS1-DS2 batteries is set to 5.0V; S7) The cutoff voltage of the DS3 and DS4 batteries is set to 3.8V; the cutoff voltage of the S8, DS5 and DS6 batteries is set to 4.2V; the cutoff voltage of the S9, DS7 and DS8 batteries is set to 4.0V; the cutoff voltage of the S10 battery Set to 3.0V); set aside for 10 minutes; constant current 0.01C discharge to a certain voltage cutoff (S1-S8 and DS1-DS6 battery cut-off voltage is set to 3.0V; S9, S10, DS7 and DS8 battery cut-off voltage setting The cycle was set to 1.5 V. The battery was charged and discharged for 30 cycles, and the impedance after 30 cycles of the battery was recorded. The test results are shown
  • the batteries S1-S10 and DS1-DS8 were subjected to a charge and discharge cycle test at 0.01 C under conditions of 25 ⁇ 1 °C.
  • the specific test procedure is: set aside for 10 minutes, constant current 0.01C charge to a certain voltage cutoff (S1-S6 and DS1-DS2 battery cut-off voltage is set to 5.0V; S7, DS3 and DS4 battery cut-off voltage is set to 3.8V
  • the cutoff voltage of the S8, DS5, and DS6 batteries is set to 4.2V; the cutoff voltage of the S9, DS7, and DS8 batteries is set to 4.0V; the cutoff voltage of the S10 battery is set to 3.0V);; 10 minutes on hold; constant current Discharge to a certain voltage cutoff (S1-S8 and DS1-DS6 battery cut-off voltage is set to 3.0V; S9, S10, DS7 and DS8 battery cut-off voltage is set to 1.5
  • a mixture of a polymer electrolyte and a sulfide solid electrolyte is coated on the surface of the positive electrode active material.

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Abstract

La présente invention concerne un matériau composite d'électrode positive pour accumulateur lithium-ion tout solide, son procédé de préparation et son application, le matériau positif d'électrode positive présentant une structure cœur-écorce, le cœur comprenant un matériau actif d'électrode positive et l'écorce comprenant un électrolyte polymère et un électrolyte solide sulfuré. Le matériau composite d'électrode positive pour accumulateur lithium-ion tout solide selon la présente invention a une procédure de préparation simple, et peut améliorer efficacement le problème d'interface entre l'électrode positive et l'électrolyte solide inorganique d'un accumulateur lithium-ion ; un accumulateur lithium-ion tout solide préparé à partir de ce matériau présente une bonne durée de vie en cycles et de meilleures performances de sécurité.
PCT/CN2017/071314 2016-01-29 2017-01-16 Matériau composite d'électrode positive pour accumulateur lithium-ion tout solide et son procédé de préparation et son application Ceased WO2017128983A1 (fr)

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CN114784276A (zh) * 2022-04-13 2022-07-22 北京理工大学 一种具有电子、离子导电性的复合材料、制备方法及其应用
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CN115117434A (zh) * 2022-07-22 2022-09-27 欣旺达电子股份有限公司 复合材料及其制备方法、固态电池以及用电设备
WO2024071928A1 (fr) * 2022-09-29 2024-04-04 삼성에스디아이주식회사 Cathode et batterie secondaire entièrement solide la comprenant
CN115579527A (zh) * 2022-10-25 2023-01-06 深圳市合壹新能技术有限公司 固态电池及其制备方法
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FR3144891A1 (fr) * 2023-01-09 2024-07-12 Arkema France Composition pour batterie tout solide et film préparé à partir de celle-ci
WO2024149954A1 (fr) * 2023-01-09 2024-07-18 Arkema France Composition pour batterie tout solide et film préparé à partir de celle-ci
CN115810757A (zh) * 2023-02-09 2023-03-17 中创新航科技股份有限公司 一种正极活性材料及含有该正极活性材料的锂离子电池
WO2024250915A1 (fr) * 2023-06-05 2024-12-12 蓝固(常州)新能源有限公司 Électrolyte à l'état solide à noyau-enveloppe/vitreux, son procédé de préparation et son utilisation
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