WO2022032585A1 - 电解液和包含电解液的电化学装置及电子装置 - Google Patents

电解液和包含电解液的电化学装置及电子装置 Download PDF

Info

Publication number
WO2022032585A1
WO2022032585A1 PCT/CN2020/108970 CN2020108970W WO2022032585A1 WO 2022032585 A1 WO2022032585 A1 WO 2022032585A1 CN 2020108970 W CN2020108970 W CN 2020108970W WO 2022032585 A1 WO2022032585 A1 WO 2022032585A1
Authority
WO
WIPO (PCT)
Prior art keywords
substituted
electrolyte
unsubstituted
compound
formula
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/CN2020/108970
Other languages
English (en)
French (fr)
Inventor
彭谢学
郑建明
唐超
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.)
Ningde Amperex Technology Ltd
Original Assignee
Ningde Amperex Technology 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 Ningde Amperex Technology Ltd filed Critical Ningde Amperex Technology Ltd
Priority to JP2021531033A priority Critical patent/JP7343583B2/ja
Priority to KR1020217016625A priority patent/KR102612374B1/ko
Priority to PCT/CN2020/108970 priority patent/WO2022032585A1/zh
Priority to EP20920769.5A priority patent/EP3985773A4/en
Priority to US17/474,335 priority patent/US12100811B2/en
Publication of WO2022032585A1 publication Critical patent/WO2022032585A1/zh
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
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0568—Liquid materials characterised by the solutes
    • 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
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0567—Liquid materials characterised by the additives
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
    • C07F9/00—Compounds containing elements of Groups 5 or 15 of the Periodic Table
    • C07F9/02—Phosphorus compounds
    • C07F9/28—Phosphorus compounds with one or more P—C bonds
    • C07F9/50—Organo-phosphines
    • C07F9/5004—Acyclic saturated phosphines
    • 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
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/056—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes
    • H01M10/0564—Accumulators with non-aqueous electrolyte characterised by the materials used as electrolytes, e.g. mixed inorganic/organic electrolytes the electrolyte being constituted of organic materials only
    • H01M10/0566—Liquid materials
    • H01M10/0569—Liquid materials characterised by the solvents
    • 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
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/483—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides for non-aqueous cells
    • 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
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H01M4/525—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy
    • 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
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H01M4/587—Carbonaceous material, e.g. graphite-intercalation compounds or CFx for inserting or intercalating light metals
    • 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 the technical field of energy storage, and in particular, to an electrolyte and an electrochemical device and an electronic device including the electrolyte.
  • Electrochemical devices such as Li-ion batteries have received extensive attention due to their high energy density, low maintenance, relatively low self-discharge, long cycle life, no memory effect, stable operating voltage, and environmental friendliness, and are widely used In the fields of portable electronic equipment (including mobile phones, notebooks, cameras and other electronic products), power tools and electric vehicles.
  • portable electronic equipment including mobile phones, notebooks, cameras and other electronic products
  • power tools and electric vehicles are widely used in the fields of portable electronic equipment (including mobile phones, notebooks, cameras and other electronic products), power tools and electric vehicles.
  • people have put forward more requirements for the power supply of electronic products, such as thinner, lighter, more diverse shapes, higher security, higher power Wait.
  • Increasing the charging voltage/increasing the capacity of the active material is the main method to improve the energy density of the battery, and these will accelerate the decomposition of the electrolyte and cause the battery to produce gas. How to stabilize high-valence transition metals and inhibit the decomposition of electrolytes is an urgent technical problem to be solved in the prior art.
  • the present application solves at least one problem in the related art by providing an electrolyte and an electrochemical device using the electrolyte.
  • the electrolyte provided by the present application can significantly improve the high temperature performance and float charge performance of the electrochemical device.
  • the application provides an electrolyte solution comprising at least one compound of formula I:
  • a 1 , A 2 and A 3 are each independently selected from the following formulae IA, IB, IC, or ID, and all three are not simultaneously IA:
  • n and m are independently selected from 0 or 1
  • n is selected from an integer from 1 to 6
  • R 11 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 1a , R 1b , R 1c and R 1d are each independently selected from hydrogen, substituted or unsubstituted C 1 -C 10 alkylene, substituted or unsubstituted C 2 -C 10 alkenylene, substituted or unsubstituted C 2 -C 10 alkynylene, substituted or unsubstituted C 3 - C 10 alkenyl, substituted or unsubstituted C 6 -C 10 aryl, substituted or unsubstituted C 3 -C 10 alicyclic hydrocarbon group,
  • R 12 is selected from substituted or unsubstituted C 1 -C 10 alkyl, substituted or unsubstituted C 2 -C 10 alkenyl, substituted or unsubstituted C 2 -C 10 alkynyl, substituted or unsubstituted C 2 -C 10 alkynyl, Substituted or unsubstituted C 3 -C 10 alkenyl, substituted or unsubstituted C 6 -C 10 aryl, substituted or unsubstituted C 3 -C 10 alicyclic hydrocarbon group, substituted or unsubstituted of heteroatom-containing functional groups,
  • the substituents are each independently selected from halogen.
  • the compound of formula I in the electrolyte comprises at least one of the following compounds:
  • the content of the compound of formula I above is 0.01% to 5% based on the total weight of the electrolyte.
  • the electrolyte solution of the present application further includes a compound containing a sulfur-oxygen double bond, which includes at least one of the following compounds: sulfolane, 1,3-propanesultone, 1,4-butanesultone , Methylene methyldisulfonate, 1,3-propanedisulfonic anhydride, vinyl sulfate, vinyl sulfite, 4-methyl vinyl sulfate, 2,4-butanesultone, 2-methyl- 1,3-Propane sultone, 1,3-butane sultone, 1-fluoro-1,3-propane sultone, 2-fluoro-1,3-propane sultone, 3- Fluoro-1,3-propane sultone, propenyl-1,3-sultone, propylene sulfate, propylene sulfite or fluorovinyl sulfate, wherein, based on the total weight of the electrolyte
  • the electrolyte solution of the present application further includes a compound containing PO bonds, which includes at least one of the following compounds: lithium difluorophosphate, lithium difluorobisoxalate, lithium tetrafluorooxalate, 1,2- Bis((difluorophosphino)oxy)ethane, trimethyl phosphate, triphenyl phosphate, triisopropyl phosphate, 3,3,3-trifluoroethyl phosphate, 3,3, 3-trifluoroethyl phosphite, tris(trimethylsilane) phosphate, pentafluoroethoxycyclotriphosphazene or pentafluoro(phenoxy)cyclotriphosphazene, wherein based on the electrolyte
  • the content of the compound containing PO bonds is 0.1% to 3% based on the total weight.
  • the electrolyte solution of the present application further includes a polynitrile compound including at least one of the following compounds: adiponitrile, succinonitrile, 1,2-bis(2-cyanoethoxy)ethane, 1,2,3-propanetricarbonitrile, 1,3,5-pentatricarbonitrile, 1,3,6-hexanetricarbonitrile, 1,2,6-hexanetricarbonitrile or 1,2,3-tris(2- cyanoethoxy)propane.
  • a polynitrile compound including at least one of the following compounds: adiponitrile, succinonitrile, 1,2-bis(2-cyanoethoxy)ethane, 1,2,3-propanetricarbonitrile, 1,3,5-pentatricarbonitrile, 1,3,6-hexanetricarbonitrile, 1,2,6-hexanetricarbonitrile or 1,2,3-tris(2- cyanoethoxy)propane.
  • the content of the compound of formula I is a%
  • the content of the polynitrile compound is b%
  • the ratio a/b of the content of the compound of formula I to the content of the polynitrile compound is greater than or equal to 0.1 and less than or equal to 80.
  • the present application also provides an electrochemical device including a positive electrode, a negative electrode, a separator, and an electrolyte solution according to the present application.
  • the electrolyte in the electrochemical device further includes a metal element, the metal element includes at least one of Cu, Co, Ni or Mn, wherein the content of the metal element in the electrolyte is less than 1000 ppm.
  • the anode in the electrochemical device includes an anode active material that includes a silicon-containing material.
  • the present application also provides an electronic device comprising the electrochemical device according to the present application.
  • a term may refer to a range of variation less than or equal to ⁇ 10% of the numerical value, such as less than or equal to ⁇ 5%, less than or equal to ⁇ 4%, less than or equal to ⁇ 3%, Less than or equal to ⁇ 2%, less than or equal to ⁇ 1%, less than or equal to ⁇ 0.5%, less than or equal to ⁇ 0.1%, or less than or equal to ⁇ 0.05%.
  • the difference between two values is less than or equal to ⁇ 10% of the mean of the values (eg, less than or equal to ⁇ 5%, less than or equal to ⁇ 4%, less than or equal to ⁇ 3%, less than or equal to ⁇ 2%, less than or equal to ⁇ 1%, less than or equal to ⁇ 0.5%, less than or equal to ⁇ 0.1%, or less than or equal to ⁇ 0.05%), then the two values are considered to be "about" the same.
  • a list of items joined by the terms "one of,” “one of,” “one of,” or other similar terms can mean that any of the listed items one.
  • the phrase “one of A and B” means A only or B only.
  • the phrase “one of A, B, and C” means A only; B only; or C only.
  • Item A may contain a single element or multiple elements.
  • Item B may contain a single element or multiple elements.
  • Item C may contain a single element or multiple elements.
  • a list of items joined by the terms "at least one of,” “at least one of,” “at least one of,” or other similar terms may mean the listed items any combination of .
  • the phrase “at least one of A and B” means A only; B only; or A and B.
  • the phrase "at least one of A, B, and C” means A only; or B only; C only; A and B (excluding C); A and C (excluding B); B and C (excluding A); or all of A, B, and C.
  • Item A may contain a single element or multiple elements.
  • Item B may contain a single element or multiple elements.
  • Item C may contain a single element or multiple elements.
  • Cn-Cm refers to a group having “n” to “m” carbon atoms, where “n” and “m” are integers.
  • C 1 -C 10 "alkyl is an alkyl group having 1 to 10 carbon atoms.
  • alkyl is intended to be a straight chain saturated hydrocarbon structure having from 1 to 20 carbon atoms. "Alkyl” is also contemplated to be a branched or cyclic hydrocarbon structure having 3 to 20 carbon atoms.
  • the alkyl group can be an alkyl group of 1 to 20 carbon atoms, an alkyl group of 1 to 10 carbon atoms, an alkyl group of 1 to 5 carbon atoms, an alkyl group of 5 to 20 carbon atoms, an alkyl group of 5 to 15 carbon atoms An alkyl group of carbon atoms or an alkyl group of 5 to 10 carbon atoms.
  • butyl is meant to include n-butyl, sec-butyl, isobutyl, tert-butyl and cyclobutyl;
  • propyl includes n-propyl, isopropyl and cyclopropyl.
  • alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, n-pentyl, isopentyl, neopentyl, cyclopentyl, methylcyclopentyl, ethylcyclopentyl, n-hexyl, isohexyl, cyclohexyl, n-heptyl, octyl, cyclopropyl, cyclobutyl, norbornyl Base et al. Additionally, alkyl groups can be optionally substituted.
  • alkenyl refers to a monovalent unsaturated hydrocarbon group which may be straight or branched and having at least one and usually 1, 2 or 3 carbon-carbon double bonds. Unless otherwise defined, the alkenyl group typically contains from 2 to 20 carbon atoms, for example, it may be alkenyl of 2 to 20 carbon atoms, alkenyl of 6 to 20 carbon atoms, alkenyl of 2 to 10 carbon atoms group or an alkenyl group of 2 to 6 carbon atoms.
  • Representative alkenyl groups include, for example, vinyl, n-propenyl, isopropenyl, n-but-2-enyl, but-3-enyl, n-hex-3-enyl, and the like. Additionally, alkenyl groups may be optionally substituted.
  • alkynyl refers to a monovalent unsaturated hydrocarbon group which may be straight or branched and having at least one and usually one, two or three carbon-carbon triple bonds. Unless otherwise defined, the alkynyl group typically contains from 2 to 20 carbon atoms, for example, it may be alkynyl of 2 to 20 carbon atoms, alkynyl of 6 to 20 carbon atoms, alkynyl of 2 to 10 carbon atoms alkynyl or alkynyl of 2 to 6 carbon atoms.
  • alkynyl groups include, for example, ethynyl, prop-2-ynyl (n-propynyl), n-but-2-ynyl, n-hex-3-ynyl, and the like. Additionally, alkynyl groups may be optionally substituted.
  • alkylene alkenylene
  • alkynylene alkynylene
  • alkylene groups include, but are not limited to, methylene, ethylene, propylene, and butylene.
  • alkenylene groups include, but are not limited to, vinylene groups, propenylene groups, and butenylene groups.
  • alkynylene groups include, but are not limited to: ethynylene, propynylene, and butynylene.
  • alkenyl means that the molecule contains a pair of adjacent carbon-carbon double bonds, that is, one carbon atom is connected to two adjacent carbon atoms through two double bonds, such as
  • aryl means a monovalent aromatic hydrocarbon having a single ring (eg, phenyl) or fused rings. Fused ring systems include those that are fully unsaturated (eg, naphthalene) as well as those that are partially unsaturated (eg, 1,2,3,4-tetrahydronaphthalene). Unless otherwise defined, the aryl group typically contains 6 to 26, 6 to 20, 6 to 15, or 6 to 10 carbon ring atoms and includes, for example, -C6-10 aryl. Representative aryl groups include, for example, phenyl, methylphenyl, propylphenyl, isopropylphenyl, benzyl, and naphth-1-yl, naphth-2-yl, and the like.
  • heterocycle or “heterocyclyl” means a substituted or unsubstituted 5 to 8 membered mono- or bicyclic non-aromatic hydrocarbon in which 1 to 3 carbon atoms are replaced by heteroatoms selected from nitrogen, oxygen or sulfur atoms .
  • heteroatoms selected from nitrogen, oxygen or sulfur atoms .
  • Examples include pyrrolidin-2-yl; pyrrolidin-3-yl; piperidinyl; morpholin-4-yl and the like, which groups may subsequently be substituted.
  • Heteroatom refers to an atom selected from N, O and S.
  • Aliphatic means a saturated, partially unsaturated or unsaturated mono-, di-, tri- or polycyclic hydrocarbon group having about 3 to 15 carbons, alternatively 3 to 12 carbons, alternatively 3 to 8 carbons carbon, or 3 to 6 carbons, or 5 or 6 carbons.
  • alicyclic hydrocarbon groups include, but are not limited to: cyclopropyl, cyclobutyl, cyclobutenyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cycloheptyl, cyclooctyl, and the like .
  • halogen may be F, Cl, Br or I.
  • cyano encompasses organics containing the organic group -CN.
  • the substituents may be selected from the group consisting of halogen, alkyl, alkenyl, aryl and heteroaryl.
  • the application provides an electrolyte solution comprising at least one compound of formula I:
  • a 1 , A 2 and A 3 are each independently selected from the following formulae IA, IB, IC, or ID, and all three are not simultaneously IA:
  • n and m are independently selected from 0 or 1
  • n is selected from an integer from 1 to 6
  • R 11 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 1a , R 1b , R 1c and R 1d are each independently selected from hydrogen, substituted or unsubstituted C 1 -C 10 alkylene, substituted or unsubstituted C 2 -C 10 alkenylene, substituted or unsubstituted C 2 -C 10 alkynylene, substituted or unsubstituted C 3 - C 10 alkenyl, substituted or unsubstituted C 6 -C 10 aryl, substituted or unsubstituted C 3 -C 10 alicyclic hydrocarbon group,
  • R 12 is selected from substituted or unsubstituted C 1 -C 10 alkyl, substituted or unsubstituted C 2 -C 10 alkenyl, substituted or unsubstituted C 2 -C 10 alkynyl, substituted or unsubstituted C 2 -C 10 alkynyl, Substituted or unsubstituted C 3 -C 10 alkenyl, substituted or unsubstituted C 6 -C 10 aryl, substituted or unsubstituted C 3 -C 10 alicyclic hydrocarbon group, substituted or unsubstituted of heteroatom-containing functional groups,
  • the substituents are each independently selected from halogen.
  • a 1 , A 2 and A 3 in the compound of formula I are selected from formula IA and formula IB, formula IB and formula IC, formula IA and formula IC, or all formula IB.
  • the compound of formula I in the electrolyte comprises at least one of the following compounds:
  • the content of the above-mentioned compound of formula I is 0.01% to 5% based on the total weight of the electrolyte; for example, the content of the compound of formula I may be about 0.01%, about 0.05%, about 0.1%, about 0.2% or is the range between any two of the above values.
  • the electrolyte further includes at least one of the following compounds: a compound containing a sulfur-oxygen double bond, a compound containing a P-O bond, a polynitrile compound, or a cyclic carbonate compound.
  • the electrolyte solution of the present application may further comprise a compound containing a sulfur-oxygen double bond, and the compound containing a sulfur-oxygen double bond may comprise at least one of the compounds of formula II-A:
  • R 21 and R 22 are each independently selected from substituted or unsubstituted C 1 -C 5 alkyl, substituted or unsubstituted C 1 -C 5 alkylene, substituted or unsubstituted C 1 -C 5 alkylene C 2 -C 10 alkenyl, substituted or unsubstituted C 2 -C 10 alkynyl, substituted or unsubstituted C 3 -C 10 alicyclic, substituted or unsubstituted C 6 -C 10 aryl group, substituted or unsubstituted C 1 -C 6 heterocyclic group (heterocyclic group includes alicyclic heterocyclic group and aromatic heterocyclic group), wherein, when substituted, the substituent is One or more of halogen atoms or functional groups containing heteroatoms, wherein R 21 and R 22 can form a closed ring structure, and the hetero atoms are selected from one or more of B, N, O, F, Si, P or S. kind
  • the sulfur-oxygen double bond-containing compound includes, but is not limited to, at least one of the following compounds:
  • the sulfur-oxygen double bond-containing compound includes at least one of the following: sulfolane, 1,3-propane sultone, 1,4-butane sultone, methylene methanedisulfonate Esters, 1,3-propanedisulfonic anhydride, vinyl sulfate, vinyl sulfite, 4-methyl vinyl sulfate, 2,4-butanesultone, 2-methyl-1,3-propanesulfonic acid Esters, 1,3-Butane Sultone, 1-Fluoro-1,3-Propane Sultone, 2-Fluoro-1,3-Propane Sultone, 3-Fluoro-1,3-Propane Sultone Acid lactone, propenyl-1,3-sultone, propylene sulfate, propylene sulfite or fluorovinyl sulfate.
  • the sulfur-oxygen double bond-containing compound includes at least one of the following: sulfolane (II-7), 1,3-propanesultone (II-12), propenyl-1,3 - Sultone (II-17), vinyl sulfate (II-18) or methylene methanedisulfonate (II-21).
  • the content of the compound containing sulfur-oxygen double bonds is 0.01% to 10%, more preferably 0.1% to 10%, based on the total weight of the electrolyte. 8%; for example, the sulfur-oxygen double bond-containing compound may be present at about 0.01%, about 0.05%, about 0.1%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7% %, about 0.8%, about 0.9%, about 1.0%, about 2.0%, about 3.0%, about 4.0%, about 5.0%, about 6.0%, about 8.0%, about 9.0%, or about 10.0%, or any of the foregoing The range between two values.
  • the compound containing the sulfur-oxygen double bond has strong anti-oxidation ability, and the positive electrode material is not easily oxidized. Thereby, the heat generation caused by the decomposition reaction of metallic lithium and the electrolyte is suppressed, and the protection of the active material is further enhanced.
  • the electrolyte solution of the present application further includes a compound containing PO bonds, which includes at least one of the following compounds: lithium difluorophosphate, lithium difluorobisoxalate, lithium tetrafluorooxalate, 1,2- Bis((difluorophosphino)oxy)ethane, trimethyl phosphate, triphenyl phosphate, triisopropyl phosphate, 3,3,3-trifluoroethyl phosphate, 3,3, 3-Trifluoroethyl phosphite, tris(trimethylsilane) phosphate, pentafluoroethoxycyclotriphosphazene or pentafluoro(phenoxy)cyclotriphosphazene.
  • a compound containing PO bonds which includes at least one of the following compounds: lithium difluorophosphate, lithium difluorobisoxalate, lithium tetrafluorooxalate, 1,2- Bis((difluorophosphino
  • the content of the compound containing PO bonds is 0.1% to 3% based on the total weight of the electrolyte; for example, the content of the compound containing PO bonds may be about 0.1%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 1.5%, about 2.0%, about 2.5%, or about 3.0%, or any two of the above range between values.
  • the electrolyte solution of the present application further includes a polynitrile compound including at least one of a dinitrile or a trinitrile compound.
  • the polynitrile compound includes, but is not limited to, at least one of the following: adiponitrile, succinonitrile, 1,2-bis(2-cyanoethoxy)ethane, 1,2, 3-Propanetricarbonitrile, 1,3,5-pentanetricarbonitrile, 1,3,6-hexanetricarbonitrile, 1,2,6-hexanetricarbonitrile or 1,2,3-tris(2-cyanoethoxy base) propane.
  • the polynitrile compound includes at least one of the following: 1,2,3-tris(2-cyanoethoxy)propane (TCEP), 1,3,6-hexanetricarbonitrile (HTCN) , 1,2-bis(2-cyanoethoxy)ethane (DENE), or adiponitrile (ADN), whose structures are shown below:
  • the mass ratio of the compound of formula I to the polynitrile compound is greater than or equal to 0.1 and less than or equal to 80; for example, the mass ratio of the compound of formula I to the polynitrile compound may be about 0.1, about 0.15, about 0.2, about 0.25, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, about 1.0, about 1.5, about 2, about 3, about 4, about 5, about 6, about 7, about 8, about 9, about 10, about 12, about 15, about 18, about 20, about 25, about 28, about 30, about 35, about 40, about 45, about 50 , about 60, about 70, about 80, or a range between any two of the above values.
  • the electrolyte may further comprise a cyclic carbonate additive comprising at least one of the compounds of formula III:
  • R 3 is selected from substituted C 1 -C 6 alkylene or substituted or unsubstituted C 2 -C 6 alkenylene; when substituted, the substituent is selected from halogen, C 1 -C 6 alkane or C 2 -C 6 alkenyl.
  • the cyclic carbonate additive includes, but is not limited to, at least one of the following compounds:
  • the cyclic carbonate additive includes at least one of fluoroethylene carbonate (FEC) or vinylene carbonate (VC).
  • FEC fluoroethylene carbonate
  • VC vinylene carbonate
  • the content of the cyclic carbonate additive is 0.01% to 30% based on the total weight of the electrolyte, for example, the content of the cyclic carbonate additive may be about 0.01%, about 0.05%, about 0.1%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 2.0 %, about 3.0%, about 4.0%, about 5.0%, about 6.0%, about 8.0%, about 9.0%, about 10%, about 15%, about 18%, about 20%, about 25%, or about 30%, Or a range between any two of the above values.
  • the compound of formula I and the cyclic carbonate additive can further help to enhance the stability of the SEI film, and at the same time can increase the flexibility of the SEI film, enhance the protection effect on the active material, and reduce the amount of the active material and the electrolyte. The probability of interfacial contact is improved, thereby improving the impedance growth caused by by-product accumulation during cycling.
  • the electrolyte of the present application further includes a boron-containing lithium salt, which includes lithium tetrafluoroborate (LiBF 4 ), lithium bisoxalatoborate (LiB(C 2 O 4 ) 2 , LiBOB), or difluorooxalate borate At least one of lithium (LiBF 2 (C 2 O 4 ), LiDFOB).
  • a boron-containing lithium salt which includes lithium tetrafluoroborate (LiBF 4 ), lithium bisoxalatoborate (LiB(C 2 O 4 ) 2 , LiBOB), or difluorooxalate borate At least one of lithium (LiBF 2 (C 2 O 4 ), LiDFOB).
  • the content of the boron-containing lithium salt is 0.01% to 3% based on the total weight of the electrolyte, for example, the content of the boron-containing lithium salt may be about 0.01% , about 0.05%, about 0.1%, about 0.2%, about 0.3%, about 0.4%, about 0.5%, about 0.6%, about 0.7%, about 0.8%, about 0.9%, about 1.0%, about 2.0%, about 3.0%, or a range between any two of the above values.
  • the electrolytic solution of the present application may further contain a non-aqueous organic solvent.
  • the non-aqueous organic solvent may comprise carbonates, carboxylates, ethers, or other aprotic solvents.
  • carbonate-based solvents include dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, dipropyl carbonate, and the like.
  • carboxylate-based solvents include methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl propionate, ethyl propionate, propyl propionate, butyl propionate, methyl butyrate , ethyl butyrate, propyl butyrate, butyl butyrate, ⁇ -butyrolactone, 2,2-difluoroethyl acetate, valerolactone, butyrolactone, 2-fluoroethyl acetate, 2,2 - Ethyl difluoroacetate, ethyl trifluoroacetate, ethyl 2,2,3,3,3-pentafluoropropionate, 2,2,3,3,4,4,4,4-heptafluorobutyric acid Methyl ester, methyl 4,4,4-trifluoro-3-(trifluoromethyl)butyrate, ethyl 2,
  • ether-based solvents include ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dibutyl ether, tetrahydrofuran, 2-methyltetrahydrofuran, bis(2,2,2- trifluoroethyl) ether, etc.
  • one non-aqueous organic solvent or a mixture of multiple non-aqueous organic solvents can be used in the electrolyte.
  • the mixing ratio can be controlled according to the desired performance of the electrochemical device.
  • the electrolyte solution of the present application may further comprise a lithium salt, which includes or is selected from at least one of organic lithium salts or inorganic lithium salts.
  • the lithium salt contains at least one of fluorine, boron or phosphorus.
  • the lithium salts of the present application include or are selected from lithium hexafluorophosphate (LiPF 6 ), lithium hexafluoroantimonate (LiSbF 6 ), lithium hexafluoroarsenate (LiAsF 6 ), lithium perfluorobutanesulfonate (LiC 4 ) F 9 SO 3 ), lithium perchlorate (LiClO 4 ), lithium aluminate (LiAlO 2 ), lithium tetrachloroaluminate (LiAlCl 4 ), lithium bissulfonimide (LiN(C x F 2x+1 SO 2 ) ) (C y F 2y+1 SO 2 ), where x and y are natural numbers), at least one of lithium chloride (LiCl) or lithium fluoride (LiF).
  • LiPF 6 lithium hexafluorophosphate
  • LiSbF 6 lithium hexafluoroarsenate
  • the concentration of the lithium salt in the electrolyte of the present application is: 0.5 mol/L to 3 mol/L, 0.5 mol/L to 2 mol/L, or 0.8 mol/L to 1.5 mol/L.
  • the electrolyte may include a combination of the following additives: a compound of formula I and a compound containing a sulfur-oxygen double bond; a compound of formula I and a lithium boron-containing salt; a compound of formula I and a polynitrile compound; a compound of formula I, a sulfur-containing compound Oxygen double bond compounds and boron-containing lithium salts; compounds of formula I, sulfur-oxygen double bond-containing compounds and polynitrile compounds; compounds of formula I, polynitrile compounds and boron-containing lithium salts.
  • the electrolyte comprises a compound of formula I and an additive of at least one of the following compounds: 1,3-propane sultone, sulfolane, vinyl sulfate, methylene methanedisulfonate, tetrafluoroboric acid Lithium, lithium difluorooxalate borate, lithium difluorophosphate, lithium tetrafluorooxalate phosphate, fluoroethylene carbonate or vinylene carbonate.
  • the present application also provides an electrochemical device including a positive electrode, a negative electrode, a separator, and an electrolyte solution according to the present application.
  • the electrolyte in the electrochemical device further includes a metal element including at least one of Cu, Co, Ni, or Mn. In some embodiments, the content of the metal element in the electrolyte is less than 1000 ppm.
  • At least one of the compound of formula I or the compound containing sulfur-oxygen double bond, the compound containing PO bond, and the polynitrile compound works together with the compound of formula I, which can effectively inhibit the metal in the positive electrode and the negative electrode current collector. Elution, maintaining the stability of the positive electrode active material structure, and suppressing corrosion of the negative electrode current collector (eg, copper foil).
  • the positive electrode of the electrochemical device includes a current collector and a positive electrode active material layer provided on the current collector.
  • the positive electrode active material layer includes a positive electrode active material including a compound that reversibly intercalates and deintercalates lithium ions (ie, a lithiated intercalation compound).
  • the positive electrode active material may include a composite oxide containing lithium and at least one selected from cobalt, manganese, and nickel.
  • the above-mentioned compound as a positive electrode active material may have a coating layer on the surface, or may be mixed with a compound having a coating layer.
  • the cladding layer may comprise an oxide from a cladding element, a hydroxide of the cladding element, an oxyhydroxide of the cladding element, an oxycarbonate of the cladding element, and a hydroxycarbonate of the cladding element ( at least one cladding element compound selected from hydroxyl carbonate.
  • the compound used for the cladding layer may be amorphous or crystalline.
  • the cladding elements used for the cladding layer may include Mg, Al, Co, K, Na, Ca, Si, Ti, V, Sn, Ge, Ga, B, As, Zr, or mixtures thereof .
  • the coating layer may be formed by any method as long as the properties of the positive electrode active material are not adversely affected by including the element in the compound.
  • the method may include any coating method known to those skilled in the art, such as spraying, dipping, and the like.
  • the positive electrode active material layer may include a binder and a conductive material.
  • the binder improves the bonding performance between the positive electrode active material particles and between the positive electrode active material particles and the current collector.
  • binders include polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, diacetyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyfluoro Ethylene, ethylene oxide-containing polymers, polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyvinylidene fluoride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated styrene-butadiene rubber, epoxy Resin, nylon, etc.
  • Conductive materials are used to provide electrical conductivity to the electrodes.
  • the conductive material may include any conductive material as long as it does not cause unwanted chemical changes.
  • examples of conductive materials include one or a mixture of conductive materials such as: natural graphite; artificial graphite; carbon black; acetylene black; ketjen black; carbon fiber; metal powder, metal fiber, etc., eg Copper, nickel, aluminum, silver, etc.; or polyphenylene derivatives, etc.
  • the current collector may include aluminum, but is not limited thereto.
  • the compacted density of the cathode active material layer is 3.2 g/cm 3 -4.5 g/cm 3 .
  • the positive active material includes lithium cobalt oxide
  • the positive active material layer has a compacted density of 3.8 g/cm 3 -4.5 g/cm 3
  • the positive active material layer may have a compacted density of about 3.8 g/cm 3 , about 3.85 g/cm 3 , about 3.9 g/cm 3 , about 4.0 g/cm 3 , about 4.1 g/cm 3 , about 4.15 g/cm 3 , about 4.2 g/cm 3 , about 4.3 g /cm 3 , about 4.5 g/cm 3 , or a range between any two values above.
  • the anode of the electrochemical device includes a current collector and an anode active material layer formed on the current collector, the anode active material layer includes an anode active material, and the anode active material may include a material that reversibly intercalates/deintercalates lithium ions , lithium metal, lithium metal alloys, materials capable of doping/dedoping lithium, or transition metal oxides.
  • the material that reversibly intercalates/deintercalates lithium ions may be a carbon material.
  • the carbon material may be any carbon-based negative active material commonly used in lithium-ion rechargeable electrochemical devices. Examples of carbon materials include crystalline carbon, amorphous carbon, and combinations thereof.
  • Crystalline carbon can be amorphous or plate-shaped, platelet-shaped, spherical or fibrous natural graphite or artificial graphite.
  • the amorphous carbon can be soft carbon, hard carbon, mesophase pitch carbonization product, fired coke, and the like. Both low-crystalline carbon and high-crystalline carbon can be used as the carbon material.
  • soft carbon and hard carbon can be generally included.
  • highly crystalline carbon material natural graphite, crystalline graphite, pyrolytic carbon, mesophase pitch-based carbon fibers, mesophase carbon microbeads, mesophase pitch, and high temperature calcined carbon (such as petroleum or coke derived from coal tar pitch can be generally included) ).
  • the negative electrode active material layer may contain a binder, and the binder may include various binder polymers, such as vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinylidene fluoride, Polyacrylonitrile, polymethyl methacrylate, polyvinyl alcohol, carboxymethyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, carboxylated polyvinyl chloride, polyvinyl fluoride, ethylene oxide-containing polymers , polyvinylpyrrolidone, polyurethane, polytetrafluoroethylene, polyethylene, polypropylene, styrene-butadiene rubber, acrylic (esterified) styrene-butadiene rubber, epoxy resin, nylon, etc., but not limited thereto.
  • PVDF-co-HFP vinylidene fluoride-hexafluoropropylene copolymer
  • PVDF-co-HFP poly
  • the negative electrode active material layer may further include a conductive material to improve electrode conductivity.
  • a conductive material can be used as the conductive material as long as it does not cause unwanted chemical changes.
  • examples of conductive materials include: carbon-based materials, such as natural graphite, artificial graphite, carbon black, acetylene black, ketjen black, carbon fiber, etc.; metal-based materials, such as copper, nickel, aluminum, silver, etc. metal powder or metal fibers; conductive polymers, such as polyphenylene derivatives, etc.; or their mixtures.
  • the current collector may be copper foil, nickel foil, stainless steel foil, titanium foil, nickel foam, copper foam, a polymer substrate clad with conductive metal, or a combination thereof.
  • the negative active material includes a silicon-containing material. In some embodiments, the negative active material includes a silicon-oxygen composite.
  • the average particle size of the anode active material particles in the electrochemical device is 5 ⁇ m to 22 ⁇ m.
  • the particles of the anode active material in the electrochemical device have a specific surface area of 1 m 2 /g to 50 m 2 /g.
  • the silicon-oxygen composite SiO x (0 ⁇ x ⁇ 2) is a porous silicon-based negative electrode active material.
  • the porous SiO x particle silicon-based negative electrode active material may also contain at least one of Li 2 SiO 3 or Li 4 SiO 4 .
  • the compacted density of the negative active material layer is 1.4 g/cm 3 -2.0 g/cm 3 , for example, the compacted density of the negative active material layer may be about 1.4 g/cm 3 , about 1.5 g/cm cm 3 , about 1.6 g/cm 3 , about 1.65 g/cm 3 , about 1.7 g/cm 3 , about 1.75 g/cm 3 , about 1.8 g/cm 3 , about 1.9 g/cm 3 , about 2.0 g/cm 3 , or a range between any two of the above values.
  • the separator of the electrochemical device comprises a polyolefin-based porous membrane, a coating (coated on the surface of the polyolefin-based porous membrane), and a polymer binder.
  • the release film comprises polyethylene (PE), ethylene-propylene copolymer, polypropylene (PP), ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-methyl methacrylate copolymer
  • PE polyethylene
  • PP polypropylene
  • PP polypropylene
  • ethylene-butene copolymer ethylene-butene copolymer
  • ethylene-hexene copolymer ethylene-methyl methacrylate copolymer
  • One or more of single-layer or multi-layer polyolefin-based porous membranes One or more of single-layer or multi-layer polyolefin-based porous membranes.
  • the coating of the isolation film includes: inorganic ceramic particles and organic matter, wherein the organic matter in the coating includes polyvinylidene fluoride, vinylidene fluoride-hexafluoropropylene copolymer, polyacrylonitrile, polyimide , acrylonitrile-butadiene copolymer, acrylonitrile-styrene-butadiene copolymer, polymethyl methacrylate, polymethyl acrylate, polyethyl acrylate, acrylic-styrene copolymer, polydimethyl acrylate At least one of siloxane, sodium polyacrylate or sodium carboxymethyl cellulose, and the inorganic ceramic particles in the coating include SiO 2 , Al 2 O 3 , CaO, TiO 2 , ZnO 2 , MgO, ZrO 2 or SnO at least one of 2 .
  • the organic matter in the coating includes polyvinylidene fluoride, vinylidene fluoride-hexafluor
  • the polymer in the coating includes polyvinylidene fluoride.
  • the electrochemical device of the present application has a charge cutoff voltage of 4.2V and above.
  • the present application also provides an electronic device comprising the electrochemical device according to the present application.
  • the electrochemical device according to the present application is suitable for electronic equipment in various fields.
  • the use of the electrochemical device of the present application is not particularly limited, and it can be used for any use known in the art.
  • the electrochemical devices of the present application may be used in, but are not limited to, the following electronic devices: notebook computers, pen input computers, mobile computers, e-book players, portable telephones, portable fax machines, portable copiers, portable printers , Headphones, VCRs, LCD TVs, Portable Cleaners, Portable CD Players, Mini Discs, Transceivers, Electronic Notepads, Calculators, Memory Cards, Portable Recorders, Radios, Backup Power, Motors, Cars, Motorcycles Cars, power-assisted bicycles, bicycles, lighting equipment, toys, game consoles, clocks, power tools, flashlights, cameras, large household batteries and lithium-ion capacitors, etc.
  • the compound of formula I provided by the application can stabilize the transition metal in the high valence state of the positive electrode, and because it contains an increased number of cyano groups and contains phosphorus elements in the material structure, it can enhance the high valence state of the positive electrode. Stability of transition metals.
  • the electrolyte of the present application significantly improves the high temperature storage performance of electrochemical devices (eg, lithium ion batteries).
  • Basic electrolyte 1 In an argon atmosphere glove box with water content ⁇ 10ppm, mix ethylene carbonate (abbreviated as EC), propylene carbonate (abbreviated as PC), diethyl carbonate (abbreviated as DEC), ethyl propionate Esters (abbreviated as EP) and propyl propionate (abbreviated as PP) were mixed uniformly according to the mass ratio of 1:1:1:1:1, and then fully dried lithium salt LiPF 6 (1mol/L) was dissolved in the above mixture to obtain base electrolyte one.
  • EC ethylene carbonate
  • PC propylene carbonate
  • DEC diethyl carbonate
  • EP ethyl propionate Esters
  • PP propyl propionate
  • Basic electrolyte 2 In an argon atmosphere glove box with water content ⁇ 10ppm, ethylene carbonate (abbreviated as EC), propylene carbonate (abbreviated as PC), diethyl carbonate (abbreviated as DEC), according to 3: The mass ratio of 3:4 is mixed evenly, and then fully dried lithium salt LiPF 6 (1 mol/L) is dissolved in the above mixture to obtain the second basic electrolyte.
  • EC ethylene carbonate
  • PC propylene carbonate
  • DEC diethyl carbonate
  • Basic electrolyte 3 In an argon atmosphere glove box with water content ⁇ 10ppm, mix ethylene carbonate (abbreviated as EC), propylene carbonate (abbreviated as PC), diethyl carbonate (abbreviated as DEC), ethyl propionate Esters (abbreviated as EP) are mixed uniformly according to the mass ratio of 1:2:6:1, and then fully dried lithium salt LiPF 6 (1mol/L) is dissolved in the above mixture to obtain basic electrolyte three.
  • EC ethylene carbonate
  • PC propylene carbonate
  • DEC diethyl carbonate
  • EP ethyl propionate Esters
  • Positive electrode 1 NCM811 (LiNi 0.8 Mn 0.1 Co 0.1 O 2 ), conductive agent acetylene black, and binder polyvinylidene fluoride (abbreviated as PVDF) in a weight ratio of 96:2:2 in an appropriate amount of N-methylpyrrolidone (abbreviated as NMP) in a solvent, fully stirring and mixing to form a uniform positive electrode slurry; coating the slurry on the positive electrode current collector aluminum foil, drying, cold pressing, and welding the tabs to obtain a positive electrode one, a positive electrode one
  • the compacted density was 3.50 g/cm 3 .
  • Positive electrode two LCO (LiCoO 2 ), conductive carbon black, conductive paste, binder polyvinylidene fluoride (abbreviated as PVDF) in a weight ratio of 97.9:0.4:0.5:1.2 in an appropriate amount of N-methylpyrrolidone ( abbreviated as NMP) in a solvent to fully stir and mix to form a uniform positive electrode slurry; coat the slurry on the positive electrode current collector aluminum foil, dry, cold-press, and weld the tabs to obtain a positive electrode two, a positive electrode two pressure
  • NMP N-methylpyrrolidone
  • Negative electrode 1 fully stir and mix graphite, binder styrene-butadiene rubber (abbreviated as SBR), and thickener sodium carboxymethyl cellulose (abbreviated as CMC) according to the weight ratio of 97.4:1.4:1.2 in an appropriate amount of deionized water. Make it into a uniform negative electrode slurry; coat the slurry on the copper foil of the negative electrode current collector, dry, cold-press, and weld the tabs to obtain a negative electrode one, and the compaction density of the negative electrode one is 1.80g/cm 3 , Graphite Dv50 is 10 ⁇ m.
  • SBR binder styrene-butadiene rubber
  • CMC thickener sodium carboxymethyl cellulose
  • Negative electrode 2 fully stir and mix graphite, silicon material (SiO), sodium carboxymethyl cellulose (CMC), and modified polyacrylic acid in an appropriate amount of deionized water in a weight ratio of 87:10:0.6:2.4 to form a uniform
  • the negative electrode slurry was obtained by coating the slurry on the copper foil of the negative electrode current collector, drying, cold pressing and welding the tabs to obtain the second negative electrode.
  • the Dv50 of the mixture was 17 ⁇ m.
  • a single-layer PE porous polymer film is used as the separator (S), with a thickness of 5 microns and a porosity of 39%.
  • the separator comprises an inorganic coating and an organic substance, wherein the inorganic coating is Al 2 O 3 , the organic matter is polyvinylidene fluoride.
  • the positive electrode, the separator and the negative electrode are stacked in order, so that the separator is placed between the positive electrode and the negative electrode to play a role of isolation, and then rolled to obtain a bare cell; the bare cell is placed in the outer packaging foil, and the prepared
  • the electrolyte is injected into the dried battery, and the preparation of the lithium ion battery is completed after the processes of vacuum packaging, standing, chemical formation, and shaping.
  • Examples 1 to 80 and Comparative Examples 1 to 5 base electrolyte one, positive electrode two and negative electrode one were used to prepare lithium ion batteries according to the methods described above, and were subjected to cycle tests and high temperature storage tests.
  • the specific test method is as follows:
  • 25 °C cycle test process under the condition of 25 °C, the battery is charged to 4.45V at 0.7C, and the constant voltage is charged to 0.05C under the condition of 4.45V. Then discharge to 3.0V with a current of 1C, test the capacity of the lithium-ion battery and denote it as C 0 , charge it with a current of 1.5C to a voltage of 4.45V, and then discharge it to 3.0V with a current of 1C as a cycle, 800 cycles were performed to test the capacity of the lithium-ion battery, and the capacity was recorded as C.
  • the cycle capacity retention rate is calculated according to the following formula:
  • Cycle capacity retention rate (%) (CC 0 ) ⁇ C 0 ⁇ 100%.
  • Thickness expansion ratio of float charge (%) (DD 0 ) ⁇ D 0 ⁇ 100%.
  • 85°C high temperature storage test process Charge the battery to 4.45V with a constant current of 0.5C at 25°C, and then charge it with a constant voltage until the current is 0.05C, test the thickness of the lithium-ion battery and record it as D 1 , and place it in an oven at 85°C During 24h, the thickness at this time was monitored and recorded as D 2 .
  • the thickness expansion rate of the lithium-ion battery after being stored at high temperature for 24h is calculated according to the following formula:
  • Thickness expansion ratio (%) (D 2 -D 1 ) ⁇ D 1 ⁇ 100%.
  • Examples 35 to 49 show the combination of the compound of formula I of the present application and the boron-containing lithium salt. It can be seen from the test results that the combination can significantly improve the high temperature storage and cycle performance of the electrochemical device.
  • Examples 50 to 66 and Example 4 that the additional addition of a compound containing a P-O bond in combination with the compound of formula I of the present application can further improve the high temperature storage performance of the electrochemical device.
  • compounds containing P-O bonds for example, lithium difluorophosphate and lithium tetrafluorooxalate phosphate
  • work together with the compound of formula I to form a film on the positive electrode which can reduce the contact between the electrolyte and the positive electrode, and play a role in inhibiting gas production.
  • the inventors of the present application have unexpectedly found that the combination of the compound of formula I of the present application and the polynitrile compound can effectively reduce the viscosity and cost of the electrolyte. It can be seen from the test results in Table 4 above that the combined use of the compound of formula I and the polynitrile compound provided by the present application can significantly improve the floating charge performance and cycle performance of the battery, but the excessive addition of the polynitrile compound will lead to electrolyte viscosity. If it is too large, the kinetics will be affected and the degree of improvement in cycle performance will be reduced.
  • Examples 83 to 90 the base electrolyte two, the positive electrode one and the negative electrode one were used to prepare lithium ion batteries according to the method described above, and were subjected to the overcharge test.
  • the substances shown in Table 5 were added on the basis of Example 4.
  • Examples 91 to 96 and Comparative Examples 6 to 7 the base electrolyte 2, the positive electrode 1 and the negative electrode 1 were used to prepare lithium ion batteries according to the method described above, and were subjected to an overcharge test.
  • the specific test method is as follows:
  • Overcharge test process discharge the battery at 25°C at 0.5C to 2.8V, charge it with 2C (6.8A) constant current to different voltages as shown in the table, and then charge it at constant voltage for 3 hours, monitor the temperature change of the battery surface, No fire or no smoke is passed, and the number of passing batteries is counted, 10 batteries are tested in each group, and the number of passing batteries is recorded.
  • Lithium-ion batteries were prepared using basic electrolyte 3, positive electrode 2 and negative electrode 2, and were subjected to a high-temperature storage test at 60 °C.
  • the specific test method is as follows:
  • Thickness expansion ratio (%) for high temperature storage at 60°C (D 4 -D 3 ) ⁇ D 3 ⁇ 100%.
  • the high temperature storage performance can be significantly improved after adding the compound of formula I according to the present application.
  • the compound of formula I of the present application can improve the stability of the interface of the positive electrode material, and the phosphorus part contained in the compound of formula I can absorb the oxygen released by the positive electrode, reduce the decomposition of the electrolyte, inhibit gas production, and improve high-temperature storage and circulation.

Landscapes

  • Chemical & Material Sciences (AREA)
  • General Chemical & Material Sciences (AREA)
  • Electrochemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Inorganic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Secondary Cells (AREA)

Abstract

一种电解液，其包括至少一种式I化合物。还提供一种电化学装置和电子装置，其包含所述的电解液。所述的电解液能够改善电化学装置的高温存储性能。

Description

电解液和包含电解液的电化学装置及电子装置 技术领域
本申请涉及储能技术领域，尤其涉及一种电解液以及包括该电解液的电化学装置及电子装置。
背景技术
由于电化学装置，如锂离子电池，具有高能量密度、低维护、相对较低的自放电、长循环寿命、无记忆效应、工作电压稳定和环境友好等特性受到人们的广泛关注，被广泛用于便携式电子设备(包括手机、笔记本、相机等电子产品)、电动工具和电动汽车等领域。然而随着技术的快速发展以及市场需求的多样性，人们对电子产品的电源也提出了更多要求，例如更薄、更轻、外形更多样化、更高的安全性、更高的功率等。
提高充电电压/增加活性物质的容量是提升电池的能量密度的主要方法，而这些都会加速电解液的分解，导致电池产气。如何能够稳定高价态的过渡金属，抑制电解液分解是现有技术中亟待解决的技术问题。
发明内容
本申请通过提供一种电解液和使用该电解液的电化学装置以解决至少一种存在于相关领域中的问题。特别地，本申请提供的电解液能够显著改善电化学装置的高温性能和浮充性能。
本申请提供一种电解液，其包括至少一种式I的化合物：
Figure PCTCN2020108970-appb-000001
其中，A 1、A 2和A 3各自独立地选自以下式I-A、I-B、I-C、或I-D，且三者不同时为I-A：
Figure PCTCN2020108970-appb-000002
Figure PCTCN2020108970-appb-000003
其中，
Figure PCTCN2020108970-appb-000004
表示与相邻原子的结合位点，
其中，m、k各自独立地选自0或1，n选自1到6的整数，
R 11、R 13、R 14、R 15、R 16、R 17、R 18、R 19、R 1a、R 1b、R 1c和R 1d各自独立地选自氢、经取代或未经取代的C 1-C 10亚烷基、经取代或未经取代的C 2-C 10亚烯基、经取代或未经取代的C 2-C 10亚炔基、经取代或未经取代的C 3-C 10的连烯基、经取代或未经取代的C 6-C 10芳基、经取代或未经取代的C 3-C 10脂环烃基，
R 12选自经取代或未经取代的C 1-C 10烷基、经取代或未经取代的C 2-C 10烯基、经取代或未经取代的C 2-C 10炔基、经取代或未经取代的C 3-C 10连烯基、经取代或未经取代的C 6-C 10芳基、经取代或未经取代的C 3-C 10脂环烃基、取代或未取代的含杂原子的官能团，
其中，经取代时，取代基各自独立选自卤素。
在一些实施例中，电解液中的式I化合物包含以下化合物的至少一种：
Figure PCTCN2020108970-appb-000005
Figure PCTCN2020108970-appb-000006
Figure PCTCN2020108970-appb-000007
在一些实施例中，基于电解液的总重量，上述式I化合物的含量为0.01％至5％。
在一些实施例中，本申请的电解液还包括含有硫氧双键的化合物，其包括以下化合物的至少一种：环丁砜、1,3-丙磺酸内酯、1,4-丁磺内酯、甲基二磺酸亚甲酯、1,3-丙二磺酸酐、硫酸乙烯酯、亚硫酸乙烯酯、4-甲基硫酸乙烯酯、2,4-丁磺内酯、2-甲基-1,3-丙磺酸内酯、1,3-丁磺酸内酯、1-氟-1,3-丙磺酸内酯、2-氟-1,3-丙磺酸内酯、3-氟-1,3-丙磺酸内酯、丙烯基-1,3-磺酸内酯、硫酸丙烯酯、亚硫酸丙烯酯或氟代硫酸乙烯酯，其中，基于电解液的总重量，上述含有硫氧双键的化合物的含量为0.01％至10％。
在一些实施例中，本申请的电解液还包括含有P-O键的化合物，其包括以下化合物的至少一种：二氟磷酸锂、二氟双草酸磷酸锂、四氟草酸磷酸锂、1,2-双((二氟膦基)氧基)乙烷、三甲基磷酸酯、三苯基磷酸酯、三异丙基磷酸酯、3,3,3-三氟乙基磷酸酯、3,3,3-三氟乙基亚磷酸酯、三(三甲基硅烷)磷酸酯、五氟乙氧基环三磷腈或五氟(苯氧基)环三磷腈，其中，基于所述电解液的总重量，所述含有P-O键的化合物的含量为0.1％至3％。
在一些实施例中，本申请的电解液还包括多腈化合物，其包括以下化合物的至少一种：己二腈、丁二腈、1,2-二(2-氰乙氧基)乙烷、1,2,3-丙三甲腈、1,3,5-戊三甲腈、1,3,6- 己三甲腈、1,2,6-己三甲腈或1,2,3-三(2-氰基乙氧基)丙烷。
在一些实施例中，基于电解液的总重量，式I化合物的含量为a％，多腈化合物的含量为b％，式I化合物的含量与多腈化合物的含量的比值a/b为大于等于0.1且小于等于80。
本申请还提供一种电化学装置，其包括正极、负极、隔离膜和根据本申请的电解液。
在一些实施例中，电化学装置中的电解液还包含金属元素，该金属元素包含Cu、Co、Ni或Mn的至少一种，其中金属元素在电解液中的含量小于1000ppm。
在一些实施例中，电化学装置中的负极包括负极活性物质，该负极活性物质包括含硅材料。
本申请还提供一种电子装置，其包含根据本申请的电化学装置。
具体实施方式
为使本申请的目的、技术方案和优点更加清楚，下面将结合实施例对本申请的技术方案进行清楚、完整地描述，显然，所描述的实施例是本申请一部分实施例，而不是全部的实施例。在此所描述的有关实施例为说明性质的且用于提供对本申请的基本理解。本申请的实施例不应该被解释为对本申请的限制。基于本申请提供的技术方案及所给出的实施例，本领域技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都属于本申请保护的范围。
如本文中所使用，术语“约”用以描述及说明小的变化。当与事件或情形结合使用时，所述术语可指代其中事件或情形精确发生的例子以及其中事件或情形极近似地发生的例子。举例来说，当结合数值使用时，术语可指代小于或等于所述数值的±10％的变化范围，例如小于或等于±5％、小于或等于±4％、小于或等于±3％、小于或等于±2％、小于或等于±1％、小于或等于±0.5％、小于或等于±0.1％、或小于或等于±0.05％。举例来说，如果两个数值之间的差值小于或等于所述值的平均值的±10％(例如小于或等于±5％、小于或等于±4％、小于或等于±3％、小于或等于±2％、小于或等于±1％、小于或等于±0.5％、小于或等于±0.1％、或小于或等于±0.05％)，那么可认为所述两个数值“约”相同。
另外，有时在本文中以范围格式呈现量、比率和其它数值。应理解，此类范围格式 是用于便利及简洁起见，且应灵活地理解，不仅包含明确地指定为范围限制的数值，而且包含涵盖于所述范围内的所有个别数值或子范围，如同明确地指定每一数值及子范围一般。
在具体实施方式及权利要求书中，由术语“中的一者”、“中的一个”、“中的一种”或其他相似术语所连接的项目的列表可意味着所列项目中的任一者。例如，如果列出项目A及B，那么短语“A及B中的一者”意味着仅A或仅B。在另一实例中，如果列出项目A、B及C，那么短语“A、B及C中的一者”意味着仅A；仅B；或仅C。项目A可包含单个元件或多个元件。项目B可包含单个元件或多个元件。项目C可包含单个元件或多个元件。
在具体实施方式及权利要求书中，由术语“中的至少一者”、“中的至少一个”、“中的至少一种”或其他相似术语所连接的项目的列表可意味着所列项目的任何组合。例如，如果列出项目A及B，那么短语“A及B中的至少一者”意味着仅A；仅B；或A及B。在另一实例中，如果列出项目A、B及C，那么短语“A、B及C中的至少一者”意味着仅A；或仅B；仅C；A及B(排除C)；A及C(排除B)；B及C(排除A)；或A、B及C的全部。项目A可包含单个元件或多个元件。项目B可包含单个元件或多个元件。项目C可包含单个元件或多个元件。
本申请中使用下列定义(除非另外明确地说明)：
为简单起见，“Cn-Cm”基团是指具有“n”至“m”个碳原子的基团，其中“n”和“m”是整数。例如，“C 1-C 10”烷基是具有1至10个碳原子的烷基。
术语“烷基”预期是具有1至20个碳原子的直链饱和烃结构。“烷基”还预期是具有3至20个碳原子的支链或环状烃结构。例如，烷基可为1至20个碳原子的烷基、1至10个碳原子的烷基、1至5个碳原子的烷基、5至20个碳原子的烷基、5至15个碳原子的烷基或5至10个碳原子的烷基。当指定具有具体碳数的烷基时，预期涵盖具有该碳数的所有几何异构体；因此，例如，“丁基”意思是包括正丁基、仲丁基、异丁基、叔丁基和环丁基；“丙基”包括正丙基、异丙基和环丙基。烷基实例包括，但不限于甲基、乙基、正丙基、异丙基、环丙基、正丁基、异丁基、仲丁基、叔丁基、环丁基、正戊基、异戊基、新戊基、环戊基、甲基环戊基、乙基环戊基、正己基、异己基、环己基、正庚基、辛基、环丙基、环丁基、降冰片基等。另外，烷基可以是任选地被取代的。
术语“烯基”是指可为直链或具支链且具有至少一个且通常1个、2个或3个碳碳 双键的单价不饱和烃基团。除非另有定义，否则所述烯基通常含有2至20个碳原子，例如可以为2至20个碳原子的烯基、6至20个碳原子的烯基、2至10个碳原子的烯基或2至6个碳原子的烯基。代表性烯基包括(例如)乙烯基、正丙烯基、异丙烯基、正-丁-2-烯基、丁-3-烯基、正-己-3-烯基等。另外，烯基可以是任选地被取代的。
术语“炔基”是指可为直链或具支链且具有至少一个且通常具有1个、2个或3个碳碳三键的单价不饱和烃基团。除非另有定义，否则所述炔基通常含有2至20个碳原子，例如可以为2至20个碳原子的炔基、6至20个碳原子的炔基、2至10个碳原子的炔基或2至6个碳原子的炔基。代表性炔基包括(例如)乙炔基、丙-2-炔基(正-丙炔基)、正-丁-2-炔基、正-己-3-炔基等。另外，炔基可以是任选地被取代的。
本文使用的术语“亚烷基”、“亚烯基”或“亚炔基”是指位于两个其它化学基团之间并且连接两个其它化学基团的上文分别定义的烷基、烯基或炔基。亚烷基的实例包括但不限于：亚甲基，亚乙基，亚丙基和亚丁基。亚烯基的实例包括但不限于：亚乙烯基，亚丙烯基和亚丁烯基。亚炔基的实例包括但不限于：亚乙炔基，亚丙炔基和亚丁炔基。
术语“连烯基”意指分子中含有一对相邻碳碳双键，即有一个碳原子通过两个双键与相邻两个碳原子连接，如
Figure PCTCN2020108970-appb-000008
术语“芳基”意指具有单环(例如，苯基)或稠合环的单价芳香族烃。稠合环系统包括那些完全不饱和的环系统(例如，萘)以及那些部分不饱和的环系统(例如，1,2,3,4-四氢萘)。除非另有定义，否则所述芳基通常含有6个到26个、6至20个、6至15个或6至10个碳环原子且包括(例如)-C 6-10芳基。代表性芳基包括(例如)苯基、甲基苯基、丙基苯基、异丙基苯基、苯甲基和萘-1-基、萘-2-基等等。
术语“杂环”或“杂环基”意指取代或未取代的5至8元单或双环非芳族烃，其中1至3个碳原子被选自氮、氧或硫原子的杂原子替换。实例包括吡咯烷-2-基；吡咯烷-3-基；哌啶基；吗啉-4-基等，这些基团随后可被取代。“杂原子”是指选自N、O和S的原子。
“脂环烃基”是指是指饱和、部分不饱和或不饱和的单、二、三或多环烃基，其具有大约3至15个碳，或者具有3至12个碳，或者3至8个碳，或者3至6个碳，或者5或6个碳。脂环烃基的实例包括但不限于：环丙基，环丁基，环丁烯基，环戊基，环戊烯基，环己基，环己烯基，环庚基，环辛基，等等。
如本文所用，术语“卤素”可为F、Cl、Br或I。
如本文所用，术语“氰基”涵盖含有机基团-CN的有机物。
当上述取代基经取代时，取代基可选自由以下组成的群组：卤素、烷基、烯基、芳基和杂芳基。
一、电解液
1、式I化合物
本申请提供一种电解液，其包括至少一种式I化合物：
Figure PCTCN2020108970-appb-000009
其中，A 1、A 2和A 3各自独立地选自以下式I-A、I-B、I-C、或I-D，且三者不同时为I-A：
Figure PCTCN2020108970-appb-000010
其中，
Figure PCTCN2020108970-appb-000011
表示与相邻原子的结合位点，
其中，m、k各自独立地选自0或1，n选自1到6的整数，
R 11、R 13、R 14、R 15、R 16、R 17、R 18、R 19、R 1a、R 1b、R 1c和R 1d各自独立地选自氢、经取代或未经取代的C 1-C 10亚烷基、经取代或未经取代的C 2-C 10亚烯基、经取代或未经取代的C 2-C 10亚炔基、经取代或未经取代的C 3-C 10的连烯基、经取代或未经取代的C 6-C 10芳基、经取代或未经取代的C 3-C 10脂环烃基，
R 12选自经取代或未经取代的C 1-C 10烷基、经取代或未经取代的C 2-C 10烯基、经取代或未经取代的C 2-C 10炔基、经取代或未经取代的C 3-C 10连烯基、经取代或未经取代的C 6-C 10芳基、经取代或未经取代的C 3-C 10脂环烃基、取代或未取代的含杂原子的官能团，
其中，经取代时，取代基各自独立选自卤素。
在一些实施例中，式I化合物中的A 1、A 2和A 3选自式I-A和式I-B、式I-B和式I-C、 式I-A和式I-C或者均为式I-B。
在一些实施例中，电解液中的式I化合物包含以下化合物的至少一种：
Figure PCTCN2020108970-appb-000012
Figure PCTCN2020108970-appb-000013
在一些实施例中，基于电解液的总重量，上述式I化合物的含量为0.01％至5％；例如，式I化合物的含量可以为约0.01％、约0.05％、约0.1％、约0.2％、约0.3％、约0.4％、约0.5％、约0.6％、约0.7％、约0.8％、约0.9％、约1.0％、约2.0％、约3.0％、约4.0％或 约5.0％，或者为上述任意两个数值之间的范围。
2、其他添加剂
在一些实施例中，电解液还包含以下化合物中的至少一种：含硫氧双键的化合物、含有P-O键的化合物、多腈化合物、或环状碳酸酯类化合物。
(1)含硫氧双键的化合物
本申请的电解液可以进一步包含含硫氧双键的化合物，该含硫氧双键的化合物可包含式II-A化合物的至少一种：
Figure PCTCN2020108970-appb-000014
其中，
R 21和R 22各自独立地选自经取代或未经取代的C 1-C 5的烷基、经取代或未经取代的C 1-C 5的亚烷基、经取代或未经取代的C 2-C 10的烯基、经取代或未经取代的C 2-C 10的炔基、经取代或未经取代的C 3-C 10的脂环基、经取代或未经取代的C 6-C 10的芳基、经取代或未经取代的C 1-C 6的杂环基团(杂环基包括脂杂环基和芳杂环基)，其中，经取代时，取代基为卤素原子或者含杂原子的官能团中的一种或几种，其中，R 21和R 22可以构成闭环结构，含杂原子选自B、N、O、F、Si、P或S一种或几种。
在一些实施例中，含硫氧双键的化合物包括，但不限于以下化合物中的至少一种：
Figure PCTCN2020108970-appb-000015
Figure PCTCN2020108970-appb-000016
在一些实施例中，含硫氧双键的化合物包括以下物质中的至少一种：环丁砜、1,3-丙磺酸内酯、1,4-丁磺内酯、甲基二磺酸亚甲酯、1,3-丙二磺酸酐、硫酸乙烯酯、亚硫酸乙烯酯、4-甲基硫酸乙烯酯、2,4-丁磺内酯、2-甲基-1,3-丙磺酸内酯、1,3-丁磺酸内酯、1-氟 -1,3-丙磺酸内酯、2-氟-1,3-丙磺酸内酯、3-氟-1,3-丙磺酸内酯、丙烯基-1,3-磺酸内酯、硫酸丙烯酯、亚硫酸丙烯酯或氟代硫酸乙烯酯。
在一些实施例中，含硫氧双键的化合物包括以下物质中的至少一种：环丁砜(II-7)、1,3-丙磺酸内酯(II-12)、丙烯基-1,3-磺酸内酯(II-17)、硫酸乙烯酯(II-18)或甲基二磺酸亚甲酯(II-21)。
在一些实施例中，当电解液中包括含硫氧双键的化合物时，基于该电解液的总重量，含硫氧双键的化合物的含量为0.01％至10％，更优选为0.1％至8％；例如，含硫氧双键的化合物的含量可以为约0.01％、约0.05％、约0.1％、约0.2％、约0.3％、约0.4％、约0.5％、约0.6％、约0.7％、约0.8％、约0.9％、约1.0％、约2.0％、约3.0％、约4.0％、约5.0％、约6.0％、约8.0％、约9.0％或约10.0％，或者为上述任意两个数值之间的范围。
根据本申请的含有硫氧双键的化合物抗氧化能力较强，在正极材料不易被氧化，另一方面，在负极析锂的情况下，其会在金属锂表面还原，形成一层保护膜，从而抑制因金属锂与电解液的分解反应导致的产热，进一步增强对活性材料的保护。
(2)含有P-O键的化合物
在一些实施例中，本申请的电解液还包括含有P-O键的化合物，其包括以下化合物的至少一种：二氟磷酸锂、二氟双草酸磷酸锂、四氟草酸磷酸锂、1,2-双((二氟膦基)氧基)乙烷、三甲基磷酸酯、三苯基磷酸酯、三异丙基磷酸酯、3,3,3-三氟乙基磷酸酯、3,3,3-三氟乙基亚磷酸酯、三(三甲基硅烷)磷酸酯、五氟乙氧基环三磷腈或五氟(苯氧基)环三磷腈。
在一些实施例中，基于电解液的总重量，含有P-O键的化合物的含量为0.1％至3％；例如，含有P-O键的化合物的含量可以为约0.1％、约0.2％、约0.3％、约0.4％、约0.5％、约0.6％、约0.7％、约0.8％、约0.9％、约1.0％、约1.5％、约2.0％、约2.5％或约3.0％，或者为上述任意两个数值之间的范围。
(3)多腈化合物
在一些实施例中，本申请的电解液还包括多腈化合物，其包括二腈或三腈化合物中的至少一种。在一些实施例中，多腈化合物包括，但不限于以下物质中的至少一种：己二腈、丁二腈、1,2-二(2-氰乙氧基)乙烷、1,2,3-丙三甲腈、1,3,5-戊三甲腈、1,3,6-己三甲腈、1,2,6-己三甲腈或1,2,3-三(2-氰基乙氧基)丙烷。
在一些实施例中，多腈化合物包括以下物质中的至少一种：1,2,3-三(2-氰乙氧基)丙烷(TCEP)、1,3,6-己三甲腈(HTCN)、1,2-二(2-氰乙氧基)乙烷(DENE)或己二腈(ADN)，其结构如下所示：
Figure PCTCN2020108970-appb-000017
在一些实施例中，当电解液中包括多腈化合物时，式I的化合物与多腈化合物的质量比为大于等于0.1且小于等于80；例如，式I的化合物与多腈化合物的质量比可以为约0.1、约0.15、约0.2、约0.25、约0.3、约0.4、约0.5、约0.6、约0.7、约0.8、约0.9、约1.0、约1.5、约2、约3、约4、约5、约6、约7、约8、约9、约10、约12、约15、约18、约20、约25、约28、、约30、约35、约40、约45、约50、约60、约70、约80，或者为以上数值中任意两者之间的范围。
(4)环状碳酸酯添加剂
在一些实施例中，电解液可以进一步包含环状碳酸酯添加剂，其包括式III化合物的至少一种:
Figure PCTCN2020108970-appb-000018
其中，R 3选自经取代的C 1-C 6亚烷基或经取代或未经取代的C 2-C 6亚烯基；经取代时，取代基选自卤素、C 1-C 6烷基或C 2-C 6烯基。
在一些实施例中，环状碳酸酯添加剂包括，但不限于以下化合物中的至少一种：
Figure PCTCN2020108970-appb-000019
Figure PCTCN2020108970-appb-000020
在一些实施例中，环状碳酸酯添加剂包括氟代碳酸乙烯酯(FEC)或碳酸亚乙烯酯(VC)中的至少一种。
在一些实施例中，当电解液包含环状碳酸酯添加剂时，基于该电解液的总重量，环状碳酸酯添加剂的含量为0.01％至30％，例如，环状碳酸酯添加剂的含量可以为约0.01％、约0.05％、约0.1％、约0.2％、约0.3％、约0.4％、约0.5％、约0.6％、约0.7％、约0.8％、约0.9％、约1.0％、约2.0％、约3.0％、约4.0％、约5.0％、约6.0％、约8.0％、约9.0％、约10％、约15％、约18％、约20％、约25％或约30％，或者为上述任意两个数值之间的范围。
在本申请中，式I化合物与环状碳酸酯添加剂共同作用可以进一步有助于增强SEI膜的稳定性，同时可以增加SEI膜的柔性，增强对活性材料的保护作用，降低活性材料与电解液的界面接触几率，从而改善循环过程中副产物累积产生的阻抗增长。
(5)含硼锂盐
在一些实施例中，本申请的电解液还包括含硼锂盐，其包括四氟硼酸锂(LiBF 4)、双草酸硼酸锂(LiB(C 2O 4) 2、LiBOB)或二氟草酸硼酸锂(LiBF 2(C 2O 4)、LiDFOB)中的至少一种。
在一些实施例中，当电解液包括含硼锂盐时，基于该电解液的总重量，含硼锂盐的含量为0.01％至3％，例如，含硼锂盐的含量可以为约0.01％、约0.05％、约0.1％、约0.2％、约0.3％、约0.4％、约0.5％、约0.6％、约0.7％、约0.8％、约0.9％、约1.0％、约2.0％、约3.0％，或者为上述任意两个数值之间的范围。
3、有机溶剂
本申请的电解液可以进一步包含非水有机溶剂。
在一些实施例中，非水有机溶剂可以包含碳酸酯、羧酸酯、醚类或其他非质子溶剂。碳酸酯类溶剂的示例包括碳酸二甲酯、碳酸二乙酯、碳酸甲乙酯、碳酸甲丙酯、碳酸乙丙酯、碳酸二丙酯等。羧酸酯类溶剂的示例包括乙酸甲酯、乙酸乙酯、乙酸正丙酯、乙酸正丁酯、丙酸甲酯、丙酸乙酯、丙酸丙酯、丙酸丁酯、丁酸甲酯、丁酸乙酯、丁酸丙酯、丁酸丁酯、γ-丁内酯、乙酸2,2-二氟乙酯、戊内酯、丁内酯、2-氟乙酸乙酯、2,2- 二氟乙酸乙酯、三氟乙酸乙酯、2,2,3,3,3-五氟丙酸乙酯、2,2,3,3,4,4,4,4-七氟丁酸甲酯、4,4,4-三氟-3-(三氟甲基)丁酸甲酯、2,2,3,3,4,4,5,5,5,5-九氟戊酸乙酯、2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-十七氟壬酸甲酯、2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-十七氟壬酸乙酯等。醚类类溶剂的示例包括乙二醇二甲醚、二乙二醇二甲醚、四乙二醇二甲醚、二丁醚、四氢呋喃、2-甲基四氢呋喃、双(2,2,2-三氟乙基)醚等。
在一些实施例中，电解液中可以使用一种非水有机溶剂，也可以使用多种非水有机溶剂混合物，当使用混合溶剂时，可以根据期望的电化学装置性能进行控制混合比。
4、锂盐
本申请的电解液可以进一步包含锂盐，其包括或选自有机锂盐或无机锂盐中的至少一种。在一些实施例中，锂盐中含有氟元素、硼元素或磷元素中的至少一种。
在一些实施例中，本申请锂盐包括或选自六氟磷酸锂(LiPF 6)、六氟锑酸锂(LiSbF 6)、六氟砷酸锂(LiAsF 6)、全氟丁基磺酸锂(LiC 4F 9SO 3)、高氯酸锂(LiClO 4)、铝酸锂(LiAlO 2)、四氯铝酸锂(LiAlCl 4)、双磺酰亚胺锂(LiN(C xF 2x+1SO 2)(C yF 2y+1SO 2)，其中x和y是自然数)、氯化锂(LiCl)或氟化锂(LiF)中的至少一种。
在一些实施例中，本申请的电解液中锂盐的浓度为：0.5mol/L至3mol/L、0.5mol/L至2mol/L或者0.8mol/L至1.5mol/L。
在一些实施例中，电解液可以包含以下添加剂的组合：式I化合物和含硫氧双键的化合物；式I化合物和含硼锂盐；式I化合物和多腈化合物；式I化合物、含硫氧双键化合物和含硼锂盐；式I化合物、含硫氧双键的化合物和多腈化合物；式I化合物、多腈化合物和含硼锂盐。
在一些实施例中，电解液包含式I化合物以及以下化合物中至少一种的添加剂：1,3-丙磺酸内酯、环丁砜、硫酸乙烯酯、甲基二磺酸亚甲酯、四氟硼酸锂、二氟草酸硼酸锂、二氟磷酸锂、四氟草酸磷酸锂、氟代碳酸乙烯酯或碳酸亚乙烯酯。
二、电化学装置
本申请还提供一种电化学装置，其包括正极、负极、隔离膜和根据本申请的电解液。
在一些实施例中，电化学装置中的电解液还包含金属元素，该金属元素包含Cu、Co、Ni或Mn的至少一种。在一些实施例中，金属元素在电解液中的含量小于1000ppm。
在本申请中，式I化合物或含有硫氧双键的化合物、含有P-O键的化合物、多腈化合物中的至少一者与式I化合物共同作用，可以有效的抑制正极以及负极集流体中金属的溶出，维持正极活性材料结构的稳定，以及抑制负极集流体(例如，铜箔)的腐蚀。
(1)正极
根据本申请的电化学装置的正极包括集流体和设置在集流体上的正极活性物质层。正极活性物质层包括正极活性物质，正极活性物质包括可逆地嵌入和脱嵌锂离子的化合物(即，锂化插层化合物)。正极活性物质可以包括包含锂以及从钴、锰和镍中选择的至少一种的复合氧化物。
上述作为正极活性物质的化合物可以具有位于表面上的包覆层，或者可以与具有包覆层的化合物混合。包覆层可以包括从包覆元素的氧化物、包覆元素的氢氧化物、包覆元素的羟基氧化物、包覆元素的碳酸氧盐(oxycarbonate)和包覆元素的碱式碳酸盐(hydroxyl carbonate)中选择的至少一种包覆元素化合物。用于包覆层的化合物可为非晶的或结晶的。在一些实施例中，用于包覆层的包覆元素可以包括Mg、Al、Co、K、Na、Ca、Si、Ti、V、Sn、Ge、Ga、B、As、Zr或它们的混合物。可以通过任何方法形成包覆层，只要不会因为在该化合物中包括所述元素而对正极活性物质的性质产生负面影响即可。例如，该方法可以包括对本领域技术人员来讲已知的任何包覆方法，例如喷涂、浸渍等。
正极活性物质层可以包括粘结剂和导电材料。粘结剂改善正极活性物质颗粒彼此间以及正极活性物质颗粒与集流体的粘结性能。在一些实施例中，粘结剂的非限制性示例包括聚乙烯醇、羧甲基纤维素、羟丙基纤维素、二乙酰基纤维素、聚氯乙烯、羧化的聚氯乙烯、聚氟乙烯、含亚乙基氧的聚合物、聚乙烯吡咯烷酮、聚氨酯、聚四氟乙烯、聚偏二氟乙烯、聚乙烯、聚丙烯、丁苯橡胶、丙烯酸(酯)化的丁苯橡胶、环氧树脂、尼龙等。
导电材料用于为电极提供导电性。导电材料可以包括任何导电的材料，只要它不引起不想要的化学变化即可。在一些实施例中，导电材料的示例包括诸如下述的导电材料中的一种或混合物：天然石墨；人造石墨；炭黑；乙炔黑；科琴黑；碳纤维；金属粉、金属纤维等，例如铜、镍、铝、银等；或聚亚苯基衍生物等。集流体可以包括铝，但不限于此。
在一些实施例中，正极活性材料层的压实密度为3.2g/cm 3-4.5g/cm 3。
在一些实施例中，正极活性材料包括锂钴氧化物，正极活性材料层的压实密度为3.8g/cm 3-4.5g/cm 3，例如，正极活性材料层的压实密度可以为约3.8g/cm 3、约3.85g/cm 3、约3.9g/cm 3、约4.0g/cm 3、约4.1g/cm 3、约4.15g/cm 3、约4.2g/cm 3、约4.3g/cm 3、约4.5g/cm 3，或者为上述任意两个数值之间的范围。
(2)负极
在一些实施例中，电化学装置的负极包括集流体和形成在集流体上的负极活性物质层，负极活性物质层包括负极活性物质，负极活性物质可以包括可逆地嵌入/脱嵌锂离子的材料、锂金属、锂金属合金、能够掺杂/脱掺杂锂的材料或过渡金属氧化物。可逆地嵌入/脱嵌锂离子的材料可以是碳材料。碳材料可以是在锂离子可再充电电化学装置中通常使用的任何碳基负极活性物质。碳材料的示例包括结晶碳、非晶碳和它们的组合。结晶碳可以是无定形的或板形的、小片形的、球形的或纤维形的天然石墨或人造石墨。非晶碳可以是软碳、硬碳、中间相沥青碳化产物、烧制焦炭等。低结晶碳和高结晶碳均可以用作碳材料。作为低结晶碳材料，可通常包括软碳和硬碳。作为高结晶碳材料，可通常包括天然石墨、结晶石墨、热解碳、中间相沥青基碳纤维、中间相碳微珠、中间相沥青和高温锻烧炭(如石油或衍生自煤焦油沥青的焦炭)。
负极活性物质层可以包含有粘合剂，且该粘合剂可以包括各种粘合剂聚合物，如二氟乙烯一六氟丙烯共聚物(PVDF-co-HFP)，聚偏二氟乙烯、聚丙烯睛、聚甲基丙烯酸甲醋、聚乙烯醇、羧甲基纤维素、羟丙基纤维素、聚氯乙烯、羧化的聚氯乙烯、聚氟乙烯、含亚乙基氧的聚合物、聚乙烯吡咯烷酮、聚氨酯、聚四氟乙烯、聚乙烯、聚丙烯、丁苯橡胶、丙烯酸(酯)化的丁苯橡胶、环氧树脂、尼龙等，但不限于此等。
负极活性物质层还可以包括导电材料来改善电极导电率。可以使用任何导电的材料作为该导电材料，只要它不引起不想要的化学变化即可。在一些实施例中，导电材料的示例包括：碳基材料，例如天然石墨、人造石墨、炭黑、乙炔黑、科琴黑、碳纤维等；金属基材料，例如包括铜、镍、铝、银等的金属粉或金属纤维；导电聚合物，例如聚亚苯基衍生物等；或它们的混合物。在一些实施例中，集流体可以为铜箔、镍箔、不锈钢箔、钛箔、泡沫镍、泡沫铜、包覆有导电金属的聚合物基板或它们的组合。
在一些实施例中，负极活性物质包括含硅材料。在一些实施例中，负极活性物质包 含硅氧复合物。
在一些实施例中，电化学装置中的负极活性物质颗粒的平均粒径为5μm至22μm。
在一些实施例中，电化学装置中的负极活性物质的粒子具有1m 2/g至50m 2/g的比表面积。
在一些实施例中，硅氧复合物SiO x(0<x<2)是多孔性硅类负极活性物质。
在一些实施例中，该多孔性SiO x粒子硅类负极活性物质也可以含有Li 2SiO 3或Li 4SiO 4中的至少一种。
在一些实施例中，负极活性材料层的压实密度为1.4g/cm 3-2.0g/cm 3，例如，负极活性材料层的压实密度可以为约1.4g/cm 3、约1.5g/cm 3、约1.6g/cm 3、约1.65g/cm 3、约1.7g/cm 3、约1.75g/cm 3、约1.8g/cm 3、约1.9g/cm 3、约2.0g/cm 3，或者为上述任意两个数值之间的范围。
(3)隔离膜
在一些实施例中，电化学装置的隔离膜包含聚烯烃类多孔膜、涂层(涂覆于聚烯烃类多孔膜的表面上)和聚合物粘合剂。
在一些实施例中，隔离膜包括聚乙烯(PE)、乙烯-丙烯共聚物、聚丙烯(PP)、乙烯-丁烯共聚物、乙烯-己烯共聚、乙烯-甲基丙烯酸甲酯共聚物中的一种或多种组成的单层或多层的聚烯烃类多孔膜。
在一些实施例中，隔离膜的涂层包括：无机陶瓷颗粒和有机物，其中，涂层中的有机物包括聚偏氟乙烯、偏氟乙烯-六氟丙烯共聚物、聚丙烯腈、聚酰亚胺、丙烯腈-丁二烯共聚物、丙烯腈-苯乙烯-丁二烯共聚物、聚甲基丙烯酸甲酯、聚丙烯酸甲酯、聚丙烯酸乙酯、丙烯酸-苯乙烯共聚物、聚二甲基硅氧烷、聚丙烯酸钠或羧甲基纤维素钠中的至少一种，涂层中的无机陶瓷颗粒包括SiO 2、Al 2O 3、CaO、TiO 2、ZnO 2、MgO、ZrO 2或SnO 2中的至少一种。
在一些实施例中，涂层中的聚合物包括聚偏二氟乙烯。
在一些实施例中，本申请的电化学装置的充电截止电压为4.2V及以上。
三、电子装置
本申请还提供一种电子装置，其包括根据本申请的电化学装置。
根据本申请的电化学装置适用于各种领域的电子设备。本申请的电化学装置的用途没有特别限定，其可用于现有技术中已知的任何用途。在一个实施例中，本申请的电化学装置可用于，但不限于以下电子装置：笔记本电脑、笔输入型计算机、移动电脑、电子书播放器、便携式电话、便携式传真机、便携式复印机、便携式打印机、头戴式立体声耳机、录像机、液晶电视、手提式清洁器、便携CD机、迷你光盘、收发机、电子记事本、计算器、存储卡、便携式录音机、收音机、备用电源、电机、汽车、摩托车、助力自行车、自行车、照明器具、玩具、游戏机、钟表、电动工具、闪光灯、照相机、家庭用大型蓄电池和锂离子电容器等。
本申请实现了以下意料不到的技术效果：本申请提供的式I化合物可以稳定正极高价态的过渡金属，由于包含增加的氰基数量且物质结构中含磷元素，其可以增强正极高价态的过渡金属的稳定性。由此，本申请的电解液显著改善了电化学装置(例如，锂离子电池)的高温存储性能。
实施例
下面结合实施例，进一步阐述本申请。应理解，这些实施例仅用于说明本申请而不用于限制本申请的范围。
实施例I
1、化合物I-13的合成
在500mL的三口瓶中加入三(2-氰基乙基)膦(38.64g，0.2mol)和150mL的正丁醇，加热回流，当完全溶解后，边搅拌边缓慢加入16.9g(0.09mol)的1,2-二溴乙烷。将混合物加热回流总共24h，然后趁热过滤，收集沉淀物，干燥，并用乙腈重结晶，得到47.3g的亚乙基-双[三-(2-氰乙基)-溴化鏻]。
将金属钠(3.8g)溶解在200mL无水乙醇中，将溶液冷却至25℃。将47.3g的亚乙基-双[三-(2-氰乙基)-溴化鏻]加到乙醇钠溶液中，并将混合物回流2小时，然后将反应混合物浓缩。过滤，用冰水洗涤以除去溴化钠，用丙酮水溶液中重结晶得到18.2g的3,3',3″,3″′-(乙烷-1,2-二基双(膦三基))四丙腈(I-13)。
Figure PCTCN2020108970-appb-000021
2、化合物I-21的合成
在100mL的圆底烧瓶中加入2.8g的二(β-氰基乙基)膦和1.9g的吡啶和40mL的氯仿，在0℃下，加入3.5g的二(β-氰基乙基)膦氯，反应2h后，用水萃取两次，每次用20mL的水，干燥，移去氯仿，用丙酮-水重结晶得到2.7g的3,3',3″,3″′-(二膦-1,1,2,2-四基)四丙腈(I-21)。
Figure PCTCN2020108970-appb-000022
实施例II
1、制备方法
1)电解液的制备
基础电解液一：在含水量<10ppm的氩气气氛手套箱中，将碳酸乙烯酯(简写为EC)、碳酸丙烯酯(简写为PC)、碳酸二乙酯(简写为DEC)、丙酸乙酯(简写为EP)、丙酸丙酯(简写为PP)，按照1:1:1:1:1的质量比混合均匀，再将充分干燥的锂盐LiPF 6(1mol/L)溶解于上述混合物，得到基础电解液一。
基础电解液二：在含水量<10ppm的氩气气氛手套箱中，将碳酸乙烯酯(简写为EC)、碳酸丙烯酯(简写为PC)、碳酸二乙酯(简写为DEC)，按照3:3:4的质量比混合均匀，再将充分干燥的锂盐LiPF 6(1mol/L)溶解于上述混合物，得到基础电解液二。
基础电解液三：在含水量<10ppm的氩气气氛手套箱中，将碳酸乙烯酯(简写为EC)、碳酸丙烯酯(简写为PC)、碳酸二乙酯(简写为DEC)、丙酸乙酯(简写为EP)，按照1:2:6:1的质量比混合均匀，再将充分干燥的锂盐LiPF 6(1mol/L)溶解于上述混合物，得到基础电解液三。
在上述各个基础电解液中分别加入根据本申请的式I化合物、其他化合物或其组合以得到各个实施例的电解液。具体添加剂的种类和含量在下文的表格中提供。
2)正极的制备：
正极一：将NCM811(LiNi 0.8Mn 0.1Co 0.1O 2)、导电剂乙炔黑、粘结剂聚偏二氟乙烯(简写为PVDF)按重量比96:2:2在适量的N-甲基吡咯烷酮(简写为NMP)溶剂中充分搅拌混合，使其形成均匀的正极浆料；将此浆料涂覆于正极集流体铝箔上，烘干、冷压、焊接极耳，得到正极一，正极一的压实密度为3.50g/cm 3。
正极二：将LCO(LiCoO 2)、导电碳黑、导电浆料、粘结剂聚偏二氟乙烯(简写为PVDF)按重量比97.9:0.4:0.5:1.2在适量的N-甲基吡咯烷酮(简写为NMP)溶剂中充分搅拌混合，使其形成均匀的正极浆料；将此浆料涂覆于正极集流体铝箔上，烘干、冷压、焊接极耳，得到正极二，正极二的压实密度为4.15g/cm 3。
3)负极的制备
负极一：将石墨、粘结剂丁苯橡胶(简写为SBR)、增稠剂羧甲基纤维素钠(简写为CMC)按照重量比97.4:1.4:1.2在适量的去离子水中充分搅拌混合，使其形成均匀的负极浆料；将此浆料涂覆于负极集流体铜箔上，烘干、冷压、焊接极耳，得到负极一，负极一的压实密度为1.80g/cm 3，石墨Dv50为10μm。
负极二：将石墨、硅材料(SiO)、羧甲基纤维素钠(CMC)、改性聚丙烯酸按照重量比87:10:0.6:2.4在适量的去离子水中充分搅拌混合，使其形成均匀的负极浆料；将此浆料涂覆于负极集流体铜箔上，烘干、冷压、焊接极耳，得到负极二，负极二的压实密度为1.70g/cm 3，石墨和硅材料的混合物的Dv50为17μm。
3)隔离膜
实施例中使用单层PE多孔聚合物薄膜作为隔离膜(S)，其厚度为5微米，孔隙率为39％，该隔离膜包含无机涂层和有机物，其中，无机涂层为Al 2O 3，有机物为聚偏二氟乙烯。
4)锂离子电池的制备：
将正极、隔离膜、负极按顺序叠好，使隔离膜处于正极和负极之间起到隔离的作用，然后卷绕得到裸电芯；将裸电芯置于外包装箔中，将制备好的电解液注入到干燥后的电池中，经过真空封装、静置、化成、整形等工序，即完成锂离子电池的制备。
2、测试方法及测试结果
实施例1至80和对比例1至5
实施例1至80和对比例1至5中使用基础电解液一、正极二和负极一来根据上文所描述的方法制备锂离子电池，并对其进行循环测试和高温存储测试。具体测试方法如下：
25℃循环测试流程：在25℃条件下，将电池以0.7C充电至4.45V，4.45V条件下恒压充电至0.05C。之后以1C的电流放电至3.0V，测试锂离子电池的容量并记为C 0，并以1.5C的电流充电至电压为4.45V，然后以1C的电流放电至3.0V的流程作为一次循环，循环进行800圈测试锂离子电池的容量，并将容量记为C。循环容量保持率率按照下式进行计算：
循环容量保持率(％)＝(C-C 0)÷C 0×100％。
45℃浮充测试流程：将电池在25℃下以0.5C放电至3.0V，再以0.5C充电至4.45V，4.45V下恒压充电至0.05C，测试锂离子电池的厚度并记为D 0，放置到45℃烘箱当中，4.45V恒压充电42天，监控厚度变化，厚度记为D，浮充的厚度膨胀率按照下式进行计算：
浮充的厚度膨胀率(％)＝(D-D 0)÷D 0×100％。
85℃高温存储测试流程：将电池在25℃下以0.5C恒流充电至4.45V，然后恒压充电至电流为0.05C，测试锂离子电池的厚度并记为D 1，放置到85℃烘箱当中24h，监控此时厚度，记为D 2。锂离子电池高温存储24h后的厚度膨胀率按照下式进行计算：
厚度膨胀率(％)＝(D 2-D 1)÷D 1×100％。
具体测试结果见下文。
表1.实施例1至34以及对比例1的电解液以及测试结果
Figure PCTCN2020108970-appb-000023
Figure PCTCN2020108970-appb-000024
通过表1的实施例和对比例可以看出，根据本申请的式I化合物可以显著改善电池的浮充和高温存储性能。以上测试结果表明，当式I化合物的含量在0.01wt％至10wt％之间时，本申请提供的式I化合物均能够稳定高价态的过渡金属，从而改善电化学装置的性能。
实施例18至34中额外添加了含硫氧双键的化合物，测试结果表明，本申请式I化合物与含硫氧双键的化合物组合使用能够进一步改善电化学装置的高温存储性能。
表2.实施例4、35至49的电解液以及测试结果
Figure PCTCN2020108970-appb-000025
通过实施例35至49示出了本申请的式I化合物与含硼锂盐组合使用的实例，从测试结果可以看出，该组合能够使电化学装置的高温存储和循环性能都得到明显改善。
表3.实施例4和50至66的电解液以及测试结果
Figure PCTCN2020108970-appb-000026
Figure PCTCN2020108970-appb-000027
通过实施例50至66与实施例4可以看出，额外添加含有P-O键的化合物与本申请的式I化合物组合能够进一步改善电化学装置的高温存储性能。这是因为含有P-O键的化合物(例如，二氟磷酸锂和四氟草酸磷酸锂)与式I化合物共同作用，在正极成膜能够减少电解液与正极接触，起到抑制产气的作用。
表4.实施例4、13、14和67至82以及对比例2至5的电解液以及测试结果
Figure PCTCN2020108970-appb-000028
Figure PCTCN2020108970-appb-000029
本申请的发明人出人意料地发现，本申请的式I化合物与多腈化合物组合使用可以有效的降低电解液黏度和成本。由以上表4中的测试结果可以看出，本申请提供的式I化合物与多腈化合物的组合使用可以显著提高电池的浮充性能以及循环性能，但多腈化合物加入量过大会导致电解液黏度过大，动力学受到影响，循环性能改善程度降低。
实施例83至90中使用基础电解液二、正极一和负极一来根据上文所描述的方法制备锂离子电池，并对其进行过充测试。实施例83至90是在实施例4的基础上添加表5所示物质。
表5.实施例4和83至90的电解液以及测试结果
Figure PCTCN2020108970-appb-000030
由以上表5中的测试结果可以看出，本申请提供的式I化合物与多种物质的组合使用可以显著提高电池的浮充性能以及高温存储性能。
实施例91至96以及对比例6至7
实施例91至96以及对比例6至7中使用基础电解液二、正极一和负极一来根据上文所描述的方法制备锂离子电池，并对其进行过充测试。具体测试方法如下：
过充测试流程：将电池在25℃下以0.5C放电至2.8V，在以2C(6.8A)恒流充电至如表所示的不同电压，再恒压充电3h，监控电池表面温度变化，不着火不冒烟即为通过，并统计通过电池的数量，每组测试10颗电池，记录通过测试电池数量。
表6.实施例91至96以及对比例6至7的电解液以及测试结果
Figure PCTCN2020108970-appb-000031
通过以上表6中的测试结果可以看出，与单独使用式I化合物或含硫氧双键的化合物相比较，将这两类类物质组合使用能够明显的改善电化学装置的过充性能。这是因为本申请使用的含硫氧双键的化合物一方面可以提高电解液的抗氧化性，另一方面可以在负极表面形成稳定的保护膜，有效的防止锂析晶并且减少与电解液直接接触，而本申请的式I化合物可以保护正极，抑制电解液分解，二者的组合能够显著提高过充性能。
实施例97至100以及对比例8
中使用基础电解液三、正极二和负极二制备锂离子电池，并对其进行60℃高温存储测试。具体测试方法如下：
60℃高温存储测试流程：将电池在25℃下以0.5C恒流充电至4.45V，然后恒压充电至电流为0.05C，测试锂离子电池的厚度并记为D 3；放置到60℃烘箱当中30天，监控此时厚度，记为D 4。按照以下公式计算锂离子电池高温存储24h后的厚度膨胀率：
60℃高温存储厚度膨胀率(％)＝(D 4-D 3)÷D 3×100％。
45℃循环测试流程：在45℃条件下，将电池以0.7C充电至4.45V，4.45V条件下恒压充电至0.05C，之后以0.5C的电流放电至3.0V，记录此次放电容量记为C 1，之后以 0.5C充电至电压为4.45V，之后以0.5C放电至3.0V的流程进行循环测试，循环进行500圈，并记录循环容量C 2。循环容量保持率率按照下式进行计算：
45℃循环容量保持率(％)＝(C 2-C 1)÷C 1×100％。
具体测试结果见表7。
表7.实施例97至100以及对比例8的电解液以及测试结果
Figure PCTCN2020108970-appb-000032
由以上结果可以看出，与对比例8相比，加入根据本申请的式I化合物后能够显著改善高温存储性能。本申请的式I化合物可以提高正极材料界面的稳定性，另外式I化合物包含的磷部分能够吸收正极释放的氧，减少电解液分解，抑制产气，起到改善高温存储和循环的作用。
整个说明书中对“一些实施例”、“部分实施例”、“一个实施例”、“另一举例”、“举例”、“具体举例”或“部分举例”的引用，其所代表的意思是在本申请中的至少一个实施例或举例包含了该实施例或举例中所描述的特定特征、结构、材料或特性。因此，在整个说明书中的各处所出现的描述，例如：“在一些实施例中”、“在实施例中”、“在一个实施例中”、“在另一个举例中”，“在一个举例中”、“在特定举例中”或“举例“，其不必然是引用本申请中的相同的实施例或示例。此外，本文中的特定特征、结构、材料或特性可以以任何合适的方式在一个或多个实施例或举例中结合。
尽管已经演示和描述了说明性实施例，本领域技术人员应该理解上述实施例不能被解释为对本申请的限制，并且可以在不脱离本申请的精神、原理及范围的情况下对实施例进行改变，替代和修改。

Claims (11)

  1. 一种电解液，其包括至少一种式I化合物：
    Figure PCTCN2020108970-appb-100001
    其中，A 1、A 2和A 3各自独立地选自以下式I-A、I-B、I-C、或I-D，且三者不同时为I-A：
    Figure PCTCN2020108970-appb-100002
    Figure PCTCN2020108970-appb-100003
    其中，
    Figure PCTCN2020108970-appb-100004
    表示与相邻原子的结合位点，
    其中，m、k各自独立地选自0或1，n选自1到6的整数，
    R 11、R 13、R 14、R 15、R 16、R 17、R 18、R 19、R 1a、R 1b、R 1c和R 1d各自独立地选自氢、经取代或未经取代的C 1-C 10亚烷基、经取代或未经取代的C 2-C 10亚烯基、经取代或未经取代的C 2-C 10亚炔基、经取代或未经取代的C 3-C 10的连烯基、经取代或未经取代的C 6-C 10芳基、经取代或未经取代的C 3-C 10脂环烃基，
    R 12选自经取代或未经取代的C 1-C 10烷基、经取代或未经取代的C 2-C 10烯基、经取代或未经取代的C 2-C 10炔基、经取代或未经取代的C 3-C 10连烯基、经取代或未经取代的C 6-C 10芳基、经取代或未经取代的C 3-C 10脂环烃基、取代或未取代的含杂原子的官能团，
    其中，经取代时，取代基各自独立选自卤素。
  2. 根据权利要求1所述的电解液，其中所述式I化合物包含以下化合物的至少一种：
    Figure PCTCN2020108970-appb-100005
    Figure PCTCN2020108970-appb-100006
    Figure PCTCN2020108970-appb-100007
  3. 根据权利要求1所述的电解液，其中，基于所述电解液的总重量，所述式I化合物的含量为0.01％至5％。
  4. 根据权利要求1所述的电解液，其还包括含有硫氧双键的化合物，其包括以下化合物的至少一种：环丁砜、1,3-丙磺酸内酯、1,4-丁磺内酯、甲基二磺酸亚甲酯、1,3-丙二磺酸酐、硫酸乙烯酯、亚硫酸乙烯酯、4-甲基硫酸乙烯酯、2,4-丁磺内酯、2-甲基-1,3-丙磺酸内酯、1,3-丁磺酸内酯、1-氟-1,3-丙磺酸内酯、2-氟-1,3-丙磺酸内酯、3-氟-1,3-丙磺酸内酯、丙烯基-1,3-磺酸内酯、硫酸丙烯酯、亚硫酸丙烯酯或氟代硫酸乙烯酯，其中，基于所述电解液的总重量，所述含有硫氧双键的化合物的含量为0.01％至10％。
  5. 根据权利要求1所述的电解液，其还包括含有P-O键的化合物，其包括以下化合物的至少一种：二氟磷酸锂、二氟双草酸磷酸锂、四氟草酸磷酸锂、1,2-双((二氟 膦基)氧基)乙烷、三甲基磷酸酯、三苯基磷酸酯、三异丙基磷酸酯、3,3,3-三氟乙基磷酸酯、3,3,3-三氟乙基亚磷酸酯、三(三甲基硅烷)磷酸酯、五氟乙氧基环三磷腈或五氟(苯氧基)环三磷腈，其中，基于所述电解液的总重量，所述含有P-O键的化合物的含量为0.1％至3％。
  6. 根据权利要求1所述的电解液，其还包括多腈化合物，其包括以下化合物的至少一种：己二腈、丁二腈、1,2-二(2-氰乙氧基)乙烷、1,2,3-丙三甲腈、1,3,5-戊三甲腈、1,3,6-己三甲腈、1,2,6-己三甲腈或1,2,3-三(2-氰基乙氧基)丙烷。
  7. 根据权利要求6所述的电解液，其中，基于所述电解液的总重量，所述式I化合物的含量为a％，所述多腈化合物的含量为b％，所述式I化合物的含量与所述多腈化合物的含量的比值a/b为大于等于0.1且小于等于80。
  8. 一种电化学装置，其包括正极、负极、隔离膜和权利要求1-7中任一项所述的电解液。
  9. 根据权利要求8所述的电化学装置，其中，所述电解液还包含金属元素，所述金属元素包含Cu、Co、Ni或Mn的至少一种，其中所述金属元素在所述电解液中的含量小于1000ppm。
  10. 根据权利要求8所述的电化学装置，其中所述负极包括负极活性物质层和负极集流体，所述负极活性物质层包含负极活性物质，所述负极活性物质包括含硅材料。
  11. 一种电子装置，其包含权利要求8至10中任一项所述的电化学装置。
PCT/CN2020/108970 2020-08-13 2020-08-13 电解液和包含电解液的电化学装置及电子装置 Ceased WO2022032585A1 (zh)

Priority Applications (5)

Application Number Priority Date Filing Date Title
JP2021531033A JP7343583B2 (ja) 2020-08-13 2020-08-13 電解液、並びに、電解液を含む電気化学装置及び電子装置
KR1020217016625A KR102612374B1 (ko) 2020-08-13 2020-08-13 전해액 및 전해액을 포함하는 전기화학장치와 전자장치
PCT/CN2020/108970 WO2022032585A1 (zh) 2020-08-13 2020-08-13 电解液和包含电解液的电化学装置及电子装置
EP20920769.5A EP3985773A4 (en) 2020-08-13 2020-08-13 Electrolyte, electrochemical device including electrolyte, and electronic device
US17/474,335 US12100811B2 (en) 2020-08-13 2021-09-14 Electrolyte, and electrochemical device and electronic device comprising the same

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2020/108970 WO2022032585A1 (zh) 2020-08-13 2020-08-13 电解液和包含电解液的电化学装置及电子装置

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US17/474,335 Continuation US12100811B2 (en) 2020-08-13 2021-09-14 Electrolyte, and electrochemical device and electronic device comprising the same

Publications (1)

Publication Number Publication Date
WO2022032585A1 true WO2022032585A1 (zh) 2022-02-17

Family

ID=76600304

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/108970 Ceased WO2022032585A1 (zh) 2020-08-13 2020-08-13 电解液和包含电解液的电化学装置及电子装置

Country Status (5)

Country Link
US (1) US12100811B2 (zh)
EP (1) EP3985773A4 (zh)
JP (1) JP7343583B2 (zh)
KR (1) KR102612374B1 (zh)
WO (1) WO2022032585A1 (zh)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115312864A (zh) * 2022-08-25 2022-11-08 珠海冠宇电池股份有限公司 一种电解液及包括该电解液的电池
CN115602925A (zh) * 2022-10-18 2023-01-13 珠海冠宇电池股份有限公司（Cn） 一种电解液及包括该电解液的电池
WO2024065582A1 (zh) * 2022-09-30 2024-04-04 宁德新能源科技有限公司 电化学装置及电子装置
WO2025232445A1 (zh) * 2024-05-10 2025-11-13 宁德新能源科技有限公司 非水电解液、锂离子电池和电子装置

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3985773A4 (en) * 2020-08-13 2022-04-20 Ningde Amperex Technology Ltd. Electrolyte, electrochemical device including electrolyte, and electronic device
CN113921904B (zh) * 2021-09-18 2024-04-05 东莞市创明电池技术有限公司 电解液和锂二次电池
CN114846668B (zh) * 2021-11-18 2024-02-23 宁德新能源科技有限公司 一种电解液和包含该电解液的电化学装置、电子装置
CN114122519B (zh) * 2021-11-23 2024-10-18 东莞新能源科技有限公司 一种电化学装置及包含该电化学装置的电子装置
CN114400375A (zh) * 2022-01-18 2022-04-26 宁德新能源科技有限公司 电解液、电化学装置及电子装置
CN114552008B (zh) * 2022-02-21 2025-01-10 宁德新能源科技有限公司 电化学装置及电子装置
CN114335734B (zh) * 2022-03-16 2022-06-28 宁德新能源科技有限公司 电解液、以及包含其的电化学装置及电子装置
CN115133137A (zh) * 2022-08-12 2022-09-30 芜湖天弋能源科技有限公司 一种用于高电压锂电池电解液的添加剂组合物、电解液以及高电压钴酸锂电池
EP4597672A1 (en) * 2022-09-29 2025-08-06 Ningde Amperex Technology Limited Electrochemical device and electronic device
FR3142042B1 (fr) * 2022-11-16 2025-07-18 Solvionic Compose a base de sel de (2-cyanoethyl)phosphonium, electrolyte et batterie le comprenant
CN117039151B (zh) * 2023-08-15 2024-12-27 张家港市国泰华荣化工新材料有限公司 一种锂离子电池电解液及含有其的锂离子电池
CN120357029A (zh) * 2025-01-08 2025-07-22 宁德新能源科技有限公司 一种二次电池和电子装置

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105609874A (zh) * 2015-12-21 2016-05-25 东莞新能源科技有限公司 电解液以及包括该电解液的锂离子电池
CN109786835A (zh) * 2019-01-25 2019-05-21 宁德新能源科技有限公司 电解液和使用其的电化学装置
CN110165219A (zh) * 2019-06-03 2019-08-23 宁德新能源科技有限公司 电化学装置
CN111342135A (zh) * 2020-03-13 2020-06-26 宁德新能源科技有限公司 电化学装置及包含其的电子装置
CN111446501A (zh) * 2020-04-08 2020-07-24 青岛滨海学院 一种含-f和-b两基团化合物的电解液及其电化学装置

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101030487B1 (ko) 2008-07-29 2011-04-21 전자부품연구원 카본나노튜브의 수직정렬을 위한 장치 및 이를 이용한 방법
KR101585147B1 (ko) * 2009-05-21 2016-01-13 삼성에스디아이 주식회사 유기전해액 및 이를 채용한 리튬전지
WO2015111676A1 (ja) 2014-01-22 2015-07-30 三菱化学株式会社 非水系電解液及びそれを用いた非水系電解液二次電池
CN107240698A (zh) * 2017-04-20 2017-10-10 深圳市沃特玛电池有限公司 一种正极材料的改性方法
WO2020092267A1 (en) * 2018-10-30 2020-05-07 Enevate Corporation Silicon-based energy storage devices with phosphorus containing electrolyte additives
KR20210072788A (ko) * 2020-03-27 2021-06-17 닝더 엠프렉스 테크놀로지 리미티드 전해액 및 전기화학장치
CN111640986B (zh) 2020-05-28 2021-05-25 珠海冠宇电池股份有限公司 一种适用于高能量密度锂离子电池的高安全性电解液
EP3985773A4 (en) * 2020-08-13 2022-04-20 Ningde Amperex Technology Ltd. Electrolyte, electrochemical device including electrolyte, and electronic device
WO2022133836A1 (zh) * 2020-12-23 2022-06-30 宁德新能源科技有限公司 电解液、电化学装置及电子装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105609874A (zh) * 2015-12-21 2016-05-25 东莞新能源科技有限公司 电解液以及包括该电解液的锂离子电池
CN109786835A (zh) * 2019-01-25 2019-05-21 宁德新能源科技有限公司 电解液和使用其的电化学装置
CN110165219A (zh) * 2019-06-03 2019-08-23 宁德新能源科技有限公司 电化学装置
CN111342135A (zh) * 2020-03-13 2020-06-26 宁德新能源科技有限公司 电化学装置及包含其的电子装置
CN111446501A (zh) * 2020-04-08 2020-07-24 青岛滨海学院 一种含-f和-b两基团化合物的电解液及其电化学装置

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115312864A (zh) * 2022-08-25 2022-11-08 珠海冠宇电池股份有限公司 一种电解液及包括该电解液的电池
WO2024041150A1 (zh) * 2022-08-25 2024-02-29 珠海冠宇电池股份有限公司 一种电解液及包括该电解液的电池
WO2024065582A1 (zh) * 2022-09-30 2024-04-04 宁德新能源科技有限公司 电化学装置及电子装置
CN115602925A (zh) * 2022-10-18 2023-01-13 珠海冠宇电池股份有限公司（Cn） 一种电解液及包括该电解液的电池
WO2025232445A1 (zh) * 2024-05-10 2025-11-13 宁德新能源科技有限公司 非水电解液、锂离子电池和电子装置

Also Published As

Publication number Publication date
KR102612374B1 (ko) 2023-12-12
KR20210074393A (ko) 2021-06-21
EP3985773A1 (en) 2022-04-20
JP2022547364A (ja) 2022-11-14
US12100811B2 (en) 2024-09-24
JP7343583B2 (ja) 2023-09-12
US20220052382A1 (en) 2022-02-17
EP3985773A4 (en) 2022-04-20

Similar Documents

Publication Publication Date Title
WO2022032585A1 (zh) 电解液和包含电解液的电化学装置及电子装置
CN114447295B (zh) 锂离子电池
CN114639872B (zh) 一种锂离子电池
CN109786824B (zh) 电解液和使用其的电化学装置
CN102856585B (zh) 非水电解质和使用该非水电解质的锂二次电池
CN106165182B (zh) 含有二羧酸的酯的电解质组合物
CN109768326B (zh) 电解液及电化学储能装置
KR102612376B1 (ko) 전해액, 전기화학장치 및 전자장치
CN111628219A (zh) 电解液和包含电解液的电化学装置及电子装置
TW201841424A (zh) 非水電解液用添加劑、非水電解液以及蓄電裝置
CN111430793B (zh) 电解液及使用其的电化学装置和电子装置
CN111342135A (zh) 电化学装置及包含其的电子装置
WO2025112997A1 (zh) 电解液添加剂、电解液和电池
CN112400249A (zh) 一种电解液及电化学装置
CN110380120A (zh) 电解液、包含所述电解液的电化学装置和电子装置
CN107017433A (zh) 非水电解液及锂离子电池
CN110854432A (zh) 电解液以及使用其的电化学装置和电子装置
CN113273011A (zh) 电解液、电化学装置及电子装置
WO2023236198A1 (zh) 电解液和电化学装置
CN118867393A (zh) 电解液添加剂、非水电解液、锂离子电池、电池模块、电池包和用电装置
CN115548442A (zh) 一种锂离子电池电解液及其锂离子电池
CN112670578A (zh) 电解液、电化学装置及电子装置
CN113711412A (zh) 电解液、电化学装置及电子装置
WO2022061582A1 (zh) 电解液、电化学装置及电子装置
WO2022056731A1 (zh) 电解液和包含电解液的电化学装置

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2021531033

Country of ref document: JP

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 20217016625

Country of ref document: KR

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 2020920769

Country of ref document: EP

Effective date: 20210902

NENP Non-entry into the national phase

Ref country code: DE