Electrolytes, secondary batteries, battery modules, battery packs, and power consumption devices

Abstract

To provide an electrolyte for solving a problem in a cycle stress that is large due to cycle expansion of a high-voltage system.SOLUTION: The present invention provides an electrolyte, a secondary battery containing the electrolyte, a battery module, a battery pack, and a power consumption device. The electrolyte contains: a fluorine-containing metallic salt containing S=O or P=O; and one or a plurality of types of titanate having a constitutional formula of Ti-(O-R1)4 where R1 is selected from a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C2-C6 alkenyl group, a C2-C6 alkynyl group, or a C1-C6 silane group.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This application relates to the technical field of lithium batteries, and more particularly to electrolytes, secondary batteries containing the same, battery modules, battery packs, and power consumption devices. [Background technology]

[0002] In recent years, as the range of applications for lithium-ion batteries has expanded, they are widely used in energy storage and power systems such as hydroelectric, thermal, wind, and solar power plants, as well as in multiple fields such as power tools, electric bicycles, electric motorcycles, electric vehicles, military equipment, and aerospace. The significant advancements in lithium-ion batteries have led to increased requirements for their energy density, cycle performance, and safety performance.

[0003] However, the safety and performance stability of lithium-ion batteries during high-voltage charging and discharging processes have not been effectively improved over time. [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] This invention was made in view of the above-mentioned problems, and aims to provide an electrolyte that solves the problem of high cycle stress caused by cycle expansion in high-voltage systems. [Means for solving the problem]

[0005] To achieve the above objective, this application provides an electrolyte, a secondary battery containing the same, a battery module, a battery pack, and a power consumption device.

[0006] The first aspect of this application is, A fluorine-containing metal salt containing S=O or P=O, A titanium ester having the structural formula Ti-(O-R1)4, wherein R1 is one or more selected from a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C2-C6 alkenyl group, a C2-C6 alkynyl group or a C1-C6 silane group, and a titanium ester A provided electrolyte contains the above.

[0007] The battery using the electrolyte of the present application has low cycle stress due to cycle expansion in a high-voltage system and little expansion of the electrode plate.

[0008] In any embodiment, preferably, the fluorine-containing metal salt is one or more selected from MSO3F and MPO2F2, M is a metal ion, and preferably, it is one of Li, Na, K or Cs.

[0009] In any embodiment, preferably, the fluorine-containing metal salt is one or more selected from LiSO3F and LiPO2F2.

[0010] In any embodiment, preferably, the titanium ester is

Chemical formula

[0011] In any embodiment, preferably, the molar ratio of the titanium ester to the fluorine-containing metal salt is 2 / 1 to 1 / 20, preferably 1 / 8 to 1 / 10. When the molar ratio of the titanium ester to the fluorine-containing metal salt is within the above range, the battery using the electrolyte of the present application has a small expansion force of the electrode plate and a small cycle stress.

[0012] In any embodiment, preferably, the fluorine-containing metal salt accounts for 0.01% to 8% of the electrolyte mass, preferably 0.1% to 5%, and more preferably 0.2% to 3%, and the titanium ester accounts for 0.01% to 8% of the electrolyte mass, preferably 0.1% to 5%, and more preferably 0.15% to 2.5%.

[0013] In any embodiment, preferably, the total of the fluorine-containing metal salt and the titanate ester accounts for 0.01 to 10%, preferably 0.1% to 8%, and more preferably 0.2% to 4% of the electrolyte mass.

[0014] In any embodiment, preferably, the electrolyte further comprises a fluorinated solvent, the fluorinated solvent being one or more selected from fluorocarbonates, fluorobenzenes, and fluoroethers, and preferably, the fluorocarbonate is [ka] At least one selected from and / or the fluorobenzene is [ka] and / or the fluoroether is [ka] (wherein R2, R3, R4, and R5 are each independently selected from a C1-C6 alkyl group and a C1-C6 fluoroalkyl group, and R6 and R7 are each independently selected from a C1-C4 alkylene group and a C1-C4 fluoroalkylene group, and R8, R9, R 10 , R 11 , R 12 , R 13 Each of these is independently selected from F or H.

[0015] By adding the fluorinated solvent to the electrolyte, the oxidation potential of the electrolyte can be further improved, the potential window of the electrolyte can be expanded, oxidative decomposition of the electrolyte can be suppressed, the destruction of SEI and CEI films can be reduced, the expansion of the electrode plates during the cycle process can be reduced, and cycle expansion stress can be reduced.

[0016] In any embodiment, preferably, the fluorocarbonate is [ka] At least one selected from and / or the fluorobenzene is [ka] And / or, the fluoroether is [ka] It is at least one of the following.

[0017] In any embodiment, the fluorinated solvent preferably accounts for 10 to 70% of the electrolyte mass.

[0018] A second aspect of the present application further provides a secondary battery comprising the electrolyte described in the first aspect of the present application.

[0019] In any embodiment, preferably, the secondary battery includes a positive electrode plate and a negative electrode plate, the positive electrode plate includes a positive electrode current collector and a positive electrode coating layer provided on at least one surface of the positive electrode current collector, the positive electrode coating layer contains a vinylidene fluoride-alkyl unit-acrylate-acrylic acid copolymer (PVdF-Ac) as an adhesive.

[0020] In any embodiment, preferably, the adhesive is of general formula (I): [ka] (In the formula, m = 60-75%, n = 5% to 10%, x = 10% to 25%, y = 3-5%, R1', R2', R3', and R4' are each independently selected from hydrogen or an optionally substituted C1-C8 alkyl group, and the substituent is at least one selected from F, Cl, and Br. R5', R6', and R7' are each independently selected from hydrogen or an optionally substituted C1-C6 alkyl group, and the substituent is at least one selected from F, Cl, and Br. R8' may be substituted with C1-C 15 The alkyl group is selected, and the substituent is at least one selected from F, Cl, and Br. R9', R 10 ', R 11 Each of the atoms is independently selected from hydrogen and an optionally substituted C1-C6 alkyl group, and the substituent is at least one selected from F, Cl, and Br. It has the structure of [the object].

[0021] In any embodiment, preferably, the positive electrode coating layer contains at least one positive electrode active material selected from lithium iron manganese phosphate, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and composites of the above compounds with other transition metals or non-transition metals.

[0022] In any embodiment, preferably, the negative electrode plate comprises a negative electrode current collector and a negative electrode coating layer provided on at least one surface of the negative electrode current collector, wherein the negative electrode coating layer contains a compound having epoxy groups or isocyanate groups, and if the negative electrode coating layer contains a compound having epoxy groups, the compound having epoxy groups contains at least two epoxy groups, and if the negative electrode coating layer contains a compound having isocyanate groups, the compound having isocyanate groups contains at least two isocyanate groups.

[0023] In any embodiment, preferably, the epoxy group-containing compound is one or more selected from bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, pentaerythritol tetraglycidyl ether, 1,4-butanediol diglycidyl ether, propylene glycol glycidyl ether, glycidyl phthalate, tetrahydrophthalate diglycidyl, 1,2-cyclohexanedicarboxylate diglycidyl, 4,4'-tetraglycidyldiaminodiphenylmethane epoxy, triglycidyl p-aminophenol, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, tetraglycidyl-1,3-bis(aminomethylcyclohexane), 9,9-bis[(2,3-glycidoxy)phenyl]fluorene, 1,4-cyclohexanedimethanol diglycidyl ether, tetraglycidyl-4,4'-diaminodiphenyl ether, and tetraglycidyl-3,4'-diaminodiphenyl ether. The compound having the isocyanate group is one or more selected from toluene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, dimethylbiphenyl diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexane diisocyanate, 1,4-phenylene diisocyanate, and norbornene diisocyanate.

[0024] A third aspect of the present application provides a battery module including the secondary battery of the second aspect of the present application.

[0025] A fourth aspect of the present application provides a battery pack including a secondary battery of the second aspect of the present application or a battery module of the third aspect of the present application.

[0026] A fifth aspect of the present application provides a power consumption device comprising at least one selected from a secondary battery according to the second aspect of the present application, a battery module according to the third aspect of the present application, or a battery pack according to the fourth aspect of the present application.

[0027] The battery module, battery pack, or power consumption device of this application includes a secondary battery according to the second embodiment of this application, and therefore has at least the same advantages as the secondary battery described in the second embodiment of this application. [Brief explanation of the drawing]

[0028] [Figure 1] This is a schematic diagram of a secondary battery according to one embodiment of the present invention. [Figure 2] Figure 1 is an exploded view of a secondary battery according to one embodiment of the present invention. [Figure 3] This is a schematic diagram of a battery module according to one embodiment of the present invention. [Figure 4] This is a schematic diagram of a battery pack according to one embodiment of the present invention. [Figure 5] Figure 4 is an exploded view of a battery pack according to one embodiment of the present invention. [Figure 6] This is a schematic diagram of a power consumption device that uses a secondary battery as a power source according to one embodiment of the present invention. [Modes for carrying out the invention]

[0029] Hereinafter, embodiments specifically disclosing the electrolyte, secondary battery, battery module, battery pack, and electrical device of the present application will be described in detail with appropriate reference to the drawings. However, unnecessary details may be omitted. For example, detailed descriptions of known matters and repeated descriptions of substantially the same structures may be omitted. This is to avoid making the following description unnecessarily long and to make it easily understandable to those skilled in the art. Furthermore, the drawings and the following description are provided to enable those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0030] The “range” disclosed herein is defined in the form of a lower bound and an upper bound, and a given range is defined by selecting one lower bound and one upper bound, the selected lower and upper bounds define the boundaries of a particular range. The range thus defined may or may not include endpoint values ​​and can be arbitrarily combined, that is, any lower bound and any upper bound can be combined to form a single range. For example, if the ranges 60-120 and 80-110 are listed for a particular parameter, it is understood that the ranges 60-110 and 80-120 are also expected. Also, if the minimum range values ​​are listed as 1 and 2, and the maximum range values ​​are listed as 3, 4 and 5, all of the ranges 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5 are expected. In this application, unless otherwise specified, the numerical range “a-b” represents an abbreviated expression for any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0 to 5" means that all real numbers between "0 to 5" are listed herein, and "0 to 5" is merely an abbreviation for combinations of these numbers. Also, when it is stated that a parameter is an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer such as 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0031] Unless otherwise specified, all embodiments of this application and any other embodiments can be combined to form new technical solutions.

[0032] Unless otherwise specified, all technical features of this application, as well as any other technical features, can be combined to form new technical proposals.

[0033] Unless otherwise specified, all steps of this invention may be performed sequentially or randomly, preferably in order. For example, the fact that the method includes steps (a) and (b) indicates that the method may include steps (a) and (b) performed in order, or steps (b) and (a) performed in order. For example, the fact that the method may further include step (c) indicates that step (c) can be added to the method in any order, for example, the method may include steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b).

[0034] Unless otherwise specified, the terms "include" and "incorporate" in this application may be in an open or closed sense. For example, "include" and "incorporate" may mean that the product includes or incorporates other components not listed, or that it includes or incorporates only the components listed.

[0035] The terms "above" and "below" used in this application include the numbers, for example, "one or more" means one or more types, and "one or more of A and B" means "A", "B", or "A and B".

[0036] Unless otherwise specified, the term "or" in this application is inclusive. For example, the expression "A or B" means "A, B, or both A and B." More specifically, the conditions A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), or both A and B are true (or exist) all satisfy the condition "A or B."

[0037] Unless otherwise specified, the content and percentages in the context of this invention are all based on mass.

[0038] For the purposes of this invention, unless otherwise specified, substituents have the following meanings.

[0039] The terms “halogen,” “halogen atom,” or “halogenation” should be understood to mean fluorine, chlorine, bromine, and iodine, in particular bromine, chlorine, or fluorine, preferably chlorine or fluorine, more preferably fluorine.

[0040] The term "alkyl group" should be understood to mean a linear or branched hydrocarbon group having a specifically specified number of carbon atoms (e.g., C1-C8, 1, 2, 3, 4, 5, 6, 7, or 8 carbon atoms), such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, 2-methylbutyl, 1-methylbutyl, 1-ethylpropyl, 1,2-dimethylpropyl, neopentyl, 1,1-dimethylpropyl, 4-methylpentyl, 3-methylpentyl, 2-methylpentyl, 1-methylpentyl, 2-ethylbutyl, 1-ethylbutyl, 3,3-dimethylbutyl, 2,2-dimethylbutyl, 1,1-dimethylbutyl, 2,3-dimethylbutyl, 1,3-dimethylbutyl, or 1,2-dimethylbutyl. The term "C1-C6-alkyl group" should be understood to mean a linear or branched hydrocarbon group having 1, 2, 3, 4, 5, or 6 carbon atoms, such as the methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, pentyl group, isopentyl group, hexyl group, 2-methylbutyl group, 1-methylbutyl group, 1-ethylpropyl group, 1,2-dimethylpropyl group, neopentyl group, 1,1-dimethylpropyl group, 4-methylpentyl group, 3-methylpentyl group, 2-methylpentyl group, 1-methylpentyl group, 2-ethylbutyl group, 1-ethylbutyl group, 3,3-dimethylbutyl group, 2,2-dimethylbutyl group, 1,1-dimethylbutyl group, 2,3-dimethylbutyl group, 1,3-dimethylbutyl group, or 1,2-dimethylbutyl group. Preferably, the alkyl group has 1, 2, 3, or 4 carbon atoms ("C1-C4-alkyl group"), such as a methyl group, ethyl group, n-propyl group, or isopropyl group.

[0041] The term "C2-C6-alkenyl group" should be understood to mean a linear or branched monovalent hydrocarbon group containing one double bond and having 2, 3, 4, 5, or 6 carbon atoms. In particular, the alkenyl group is a C2-C3-alkenyl group, a C3-C6-alkenyl group, or a C3-C4-alkenyl group. The alkenyl group is, for example, a vinyl group, an allyl group, an (E)-2-methylvinyl group, an (Z)-2-methylvinyl group, or an isopropenyl group.

[0042] The term "C2-C6-alkynyl group" should be understood to mean a linear or branched monovalent hydrocarbon group containing one triple bond and 2, 3, 4, 5, or 6 carbon atoms. In particular, the alkynyl group is a C2-C3-alkynyl group, a C3-C6-alkynyl group, or a C3-C4-alkynyl group. The C2-C3-alkynyl group is, for example, an ethynyl group, a prop-1-inyl group, or a prop-2-inyl group.

[0043] The term "C1-C4-alkylene group" should be understood to mean a straight-chain, divalent, and saturated hydrocarbon group having 1 to 4 carbon atoms, particularly 2, 3, or 4 carbon atoms (for example, in "C2-C4-alkylene group"), such as an ethylene group, n-propylene group, n-butylidene group, n-pentylene group, or n-hexylene group, preferably an n-propylene group or n-butylidene group.

[0044] The term "C1-C6-silane group" should be understood to mean a linear or branched Si-alkyl group containing 1, 2, 3, 4, 5, or 6 carbon atoms, such as (but not limited to) the trimethylsilyl group and the triethylsilyl group.

[0045] "Haloalkyl group," "haloalkenyl group," "haloalkynyl group," and "haloalkylene group" refer to alkyl, alkenyl, alkynyl, and alkylene groups that are partially or completely substituted with the same or different halogen atoms, respectively. Examples include monohaloalkyl groups such as CH2CH2Cl, CH2CH2Br, CHClCH3, CH2Cl, and CH2F; perhaloalkyl groups such as CCl3, CClF2, CFCl2, CF2CClF2, and CF2CClFCF3; and haloalkyl groups such as CH2CHFCl, CF2CClFH, CF2CBrFH, and CH2CF3. The term perhaloalkyl group further includes the term perfluoroalkyl group.

[0046] In this invention, "C1-C8" should be interpreted as including any subranges such as C1-C8, C1-C7, C1-C6, C1-C5, C1-C4, C1-C3, C1-C2, C2-C8, C2-C7, C2-C6, C2-C5, C2-C4, C2-C3, C3-C8, C3-C7, C3-C6, C3-C5, C3-C4, C4-C8, C4-C7, C4-C6, C4-C5, C5-C8, C5-C7, C5-C6, C6-C8, C6-C7, C7-C8, etc.

[0047] Similarly, the term "C1-C6" should be interpreted as including any subranges such as C1-C6, C1-C5, C1-C4, C1-C3, C1-C2, C2-C6, C2-C5, C2-C4, C2-C3, C3-C6, C3-C5, C3-C4, C4-C6, C4-C5, and C5-C6.

[0048] Similarly, the term "C1-C4" should be interpreted as including any subranges such as C1-C4, C1-C3, C1-C2, C2-C4, C2-C3, C3-C4, etc.

[0049] Similarly, the term "C2-C6" should be interpreted as including any subranges such as C2-C5, C2-C4, C2-C3, C3-C4, C3-C5, C3-C6, C4-C5, C4-C6, C5-C6, etc.

[0050] In order to improve the energy density of the battery, improving the operating potential of the positive electrode material has become a major strategy for researchers. For example, the operating voltage of ordinary ternary positive electrode materials has risen above 4.4V. For example, positive electrode materials with higher voltages and gram capacities such as lithium-rich layered positive electrodes, spinel oxide LiNi 0.5 Mn 1.5 O4, etc., have a high operating voltage and the voltage upper limit approaches 5V. The inventor of the present application has found that when the voltage rises, the oxidation resistance of the electrolyte is lost, reducing the performance of the entire battery. Also, when the operating voltage of the positive electrode material rises, the amount of lithium removed from the positive electrode material increases, and the volumes of the positive electrode material and the negative electrode material change accordingly. Furthermore, the total volume of the cell changes significantly during the charge and discharge process of the cell. If the free electrolyte inside the cell is squeezed out and the electrolyte cannot be timely refluxed into the cell, lithium precipitation occurs due to kinetic saturation during the cycling process of the cell, and the cycle expansion of the cell increases, causing wrinkles on the cell plates. In more serious cases, a short circuit of the cell occurs, causing safety problems and greatly affecting the reliability of the cell.

[0051] As a result of a large number of experiments, the inventor of the present application has found that when the electrolyte of the high-voltage system contains a fluorine-containing metal salt containing S=O or P=O, and a titanate having the structural formula Ti-(O-R1)4, wherein the R1 is one or more selected from a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C2-C6 alkenyl group, a C2-C6 alkynyl group or a C1-C6 silane group, the cycle expansion of the cell can be significantly suppressed and the cycle expansion stress can be significantly reduced.

[0052] [Electrolyte] The first aspect of the present application is a fluorine-containing metal salt containing S=O or P=O, and A titanate ester having the structural formula Ti-(O-R1)4, wherein R1 is one or more selected from C1-C6 alkyl groups, C1-C6 haloalkyl groups, C2-C6 alkenyl groups, C2-C6 alkynyl groups, or C1-C6 silane groups, and The present invention provides an electrolyte solution containing the following:

[0053] The inventors unexpectedly discovered that adding the above-mentioned additive to the electrolyte resulted in low cycle stress in batteries using the electrolyte of the present invention. During the charging and discharging process of the cell, the electrolyte of the present invention forms a multidimensional network-like, tough polymer and inorganic composite SEI film on the positive and negative electrodes, significantly reducing cycle stress.

[0054] In some embodiments, the fluorine-containing metal salt is preferably one or more selected from MSO3F and MPO2F2, where M is a metal ion, preferably one of Li, Na, K, or Cs.

[0055] In some embodiments, the fluorine-containing metal salt is preferably one or more selected from LiSO3F and LiPO2F2.

[0056] In any embodiment, preferably, the titanate ester is [ka] It is one or more types selected from the following.

[0057] In some embodiments, the molar ratio of the titanate ester to the fluorine-containing metal salt is preferably 2 / 1 to 1 / 20, and more preferably 1 / 8 to 1 / 10. When the molar ratio of the titanate ester to the fluorine-containing metal salt is within the above range, the battery using the electrolyte of the present invention exhibits reduced plate expansion and reduced cycle stress. By controlling the molar ratio of the titanate ester to the fluorine-containing metal salt, the corresponding SEI film has good bonding force to the positive and negative electrode active materials and good toughness. If the molar ratio is too high, the flexibility of the SEI film decreases, and the effect of suppressing cycle expansion decreases. If the molar ratio is too low, the SEI film becomes more brittle, the plate expands further, and the cycle stress of the cell increases.

[0058] In some embodiments, the fluorine-containing metal salt preferably accounts for 0.01% to 8%, preferably 0.1% to 5%, and more preferably 0.2% to 3% of the electrolyte mass, and the titanate ester preferably accounts for 0.01% to 8%, preferably 0.1% to 5%, and more preferably 0.15% to 2.5% of the electrolyte mass.

[0059] In some embodiments, preferably, the total of the fluorine-containing metal salt and the titanate ester accounts for 0.01 to 10%, preferably 0.1% to 8%, and more preferably 0.2% to 4% of the electrolyte mass.

[0060] In some embodiments, preferably, the electrolyte further comprises a fluorinated solvent, the fluorinated solvent being one or more selected from fluorocarbonates, fluorobenzenes, and fluoroethers, and preferably, the fluorocarbonate is [ka] At least one selected from and / or the fluorobenzene is [ka] And / or, the fluoroether is [ka] (wherein R2, R3, R4, and R5 are each independently selected from a C1-C6 alkyl group and a C1-C6 fluoroalkyl group, and R6 and R7 are each independently selected from a C1-C4 alkylene group and a C1-C4 fluoroalkylene group, and R8, R9, R 10 , R 11 , R 12 , R 13 Each of these is independently selected from F or H.

[0061] The inventors of this application have found that when the operating voltage of the positive electrode material increases, the oxidation resistance of the ordinary electrolyte solvent is lost, and by adding the fluorinated solvent to the electrolyte, the oxidation potential of the electrolyte is further improved, the potential window of the electrolyte is expanded, oxidative decomposition of the electrolyte is suppressed, the destruction of the SEI and CEI films is reduced, the expansion of the electrode plate during the cycle process is reduced, and the cycle expansion stress is reduced.

[0062] In some embodiments, preferably, the fluorocarbonate is [ka] At least one selected from and / or the fluorobenzene is [ka] And / or, the fluoroether is [ka] It is at least one of the following.

[0063] In some embodiments, the fluorinated solvent preferably accounts for 10 to 70% of the electrolyte mass. If the content is too high, it significantly affects the conductivity of the electrolyte and further affects the power performance of the cell, while if the content is too low, the effect of suppressing cycle expansion is reduced.

[0064] In some embodiments, the electrolyte contains at least one lithium salt selected from lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonylimide, lithium bistrifluoromethanesulfonylimide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalatoborate, lithium bisoxalatoborate, lithium difluorobisoxalatophosphate, and lithium tetrafluorooxalatophosphate. Preferably, the lithium salt accounts for 10 to 14% of the electrolyte mass.

[0065] In some embodiments, the electrolyte contains at least one organic solvent selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone.

[0066] In some embodiments, the electrolyte preferably further comprises additives. For example, the additives may include negative electrode film-forming additives, positive electrode film-forming additives, and further additives that can improve some performance aspects of the battery, such as additives that improve the overcharge performance of the battery, or additives that improve the high-temperature or low-temperature performance of the battery.

[0067] [Positive electrode plate] The positive electrode plate comprises a positive electrode current collector and a positive electrode coating layer installed on at least one surface of the positive electrode current collector, wherein the positive electrode coating layer contains a vinylidene fluoride-alkyl unit-acrylate-acrylic acid copolymer (PVdF-Ac) as an adhesive. The adhesive can further suppress the cyclic expansion of the positive electrode plate and reduce cyclic stress. The small amount of COOH and ester bonds contained in the adhesive have strong van der Waals forces and hydrogen bonding with the corresponding components of the CEI film, increasing the force between the surface of the positive electrode material and the adhesive, further suppressing the expansion of the positive electrode plate and reducing the cyclic stress of the cell. Furthermore, because the adhesive molecular chain has low regularity, low crystallinity, and contains copolymerized alkyl chain units, its material is soft, highly flexible, and has high tensile strength, thus further suppressing cyclic expansion.

[0068] In some embodiments, the adhesive is preferably of general formula (I): [ka] (In the formula, m = 60-75%, n = 5% to 10%, x = 10% to 25%, y = 3-5%, R1', R2', R3', and R4' are each independently selected from hydrogen or an optionally substituted C1-C8 alkyl group, and the substituent is at least one selected from F, Cl, and Br. R5', R6', and R7' are each independently selected from hydrogen or an optionally substituted C1-C6 alkyl group, and the substituent is at least one selected from F, Cl, and Br. R8' may be substituted with C1-C 15 The alkyl group is selected, and the substituent is at least one selected from F, Cl, and Br. R9', R 10 ', R 11Each of the atoms is independently selected from hydrogen and an optionally substituted C1-C6 alkyl group, and the substituent is at least one selected from F, Cl, and Br. It has the structure of [the object].

[0069] In the above general formula (I), m, n, x, and y represent the ratio of each monomer in the polymer, preferably m + n + x + y = 100%.

[0070] In some embodiments, the positive electrode current collector may be a metal foil sheet or a composite current collector. For example, aluminum foil may be used as the metal foil sheet. The composite current collector may include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector may be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy) on a polymer material substrate (for example, a substrate such as polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), or polyethylene (PE)).

[0071] In some embodiments, the positive electrode active material may be any positive electrode active material for batteries known in the art. For example, the positive electrode active material may include at least one of olivine-structured lithium-containing phosphates, lithium transition metal oxides, and modified compounds thereof. However, the present application is not limited to these materials, and other conventional materials used as positive electrode active materials for batteries may be used. These positive electrode active materials may be used individually or in combination of two or more. Examples of lithium transition metal oxides include lithium cobalt oxide (e.g., LiCoO2), lithium nickel oxide (e.g., LiNiO2), lithium manganese oxide (e.g., LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, and lithium nickel cobalt manganese oxide (e.g., LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2(NCM333 (May also be called) LiNi 0.5 Co 0.2 Mn 0.3 O2(NCM 523 (May also be called) LiNi 0.5 Co 0.25 Mn 0.25 O2(NCM 211 (May also be called) LiNi 0.6 Co 0.2 Mn 0.2 O2(NCM 622 (May also be called) LiNi 0.8 Co 0.1 Mn 0.1 O2(NCM 811 (May also be called), lithium nickel cobalt aluminum oxide (e.g., LiNi 0.85 Co 0.15 Al 0.05 It may contain, but is not limited to, at least one of O2) and modified compounds thereof. Examples of lithium-containing phosphates with an olivine structure may include, but is not limited to, at least one of lithium iron phosphate and carbon complexes, lithium manganese phosphate (e.g., LiMnPO4), lithium manganese phosphate and carbon complexes, lithium iron manganese phosphate, and lithium iron manganese phosphate and carbon complexes.

[0072] In some embodiments, the positive electrode coating layer preferably further comprises a conductive agent. For example, the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0073] In some embodiments, the positive electrode plate may be manufactured by dispersing the above-mentioned components for manufacturing the positive electrode plate, such as a positive electrode active material, a conductive agent, and an adhesive, and any other components in a solvent (e.g., N-methylpyrrolidone) to form a positive electrode slurry, applying the positive electrode slurry to a positive electrode current collector, and obtaining the positive electrode plate by performing processes such as drying and cold pressing.

[0074] [Negative electrode plate] The negative electrode plate includes a negative electrode current collector and a negative electrode coating layer installed on at least one surface of the negative electrode current collector. The negative electrode coating layer contains a compound having epoxy groups or isocyanate groups. If the negative electrode coating layer contains a compound having epoxy groups, the compound having epoxy groups contains at least two epoxy groups. If the negative electrode coating layer contains a compound having isocyanate groups, the compound having isocyanate groups contains at least two isocyanate groups. These negative electrode additives can chemically react with stabilizers in the negative electrode slurry and groups such as COOH and OH on the adhesive surface. This allows the stabilizers and adhesive in the negative electrode slurry to be linked by the compounds containing epoxy groups or isocyanate groups, further resulting in a more complete coating of the surface of the negative electrode active material with the adhesive, and further limiting the volume expansion of the negative electrode active material after lithium intercalation, thereby reducing the cyclic expansion stress of the cell.

[0075] In some embodiments, preferably, the epoxy group-containing compound is one or more selected from bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, pentaerythritol tetraglycidyl ether, 1,4-butanediol diglycidyl ether, propylene glycol glycidyl ether, glycidyl phthalate, tetrahydrophthalate diglycidyl, 1,2-cyclohexanedicarboxylate diglycidyl, 4,4'-tetraglycidyldiaminodiphenylmethane epoxy, triglycidyl p-aminophenol, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, tetraglycidyl-1,3-bis(aminomethylcyclohexane), 9,9-bis[(2,3-glycidoxy)phenyl]fluorene, 1,4-cyclohexanedimethanol diglycidyl ether, tetraglycidyl-4,4'-diaminodiphenyl ether, and tetraglycidyl-3,4'-diaminodiphenyl ether. The compound having the isocyanate group is one or more selected from toluene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, dimethylbiphenyl diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexane diisocyanate, 1,4-phenylene diisocyanate, and norbornene diisocyanate.

[0076] In some embodiments, the negative electrode current collector may be a metal foil sheet or a composite current collector. For example, copper foil may be used as the metal foil sheet. The composite current collector may include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector may be formed by forming a metal material (such as copper, copper alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys) on a polymer material substrate (for example, a substrate such as polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), or polyethylene (PE)).

[0077] In some embodiments, the negative electrode active material may be any negative electrode active material known in the art for batteries. For example, the negative electrode active material may include at least one of artificial graphite, natural graphite, soft carbon, hard carbon, silicon materials, tin materials, and lithium titanate. The silicon material may be at least one selected from elemental silicon, silicon oxygen compounds, silicon carbon composites, silicon nitrogen composites, and silicon alloys. The tin material may be at least one selected from elemental tin, tin oxygen compounds, and tin alloys. However, the present application is not limited to these materials, and other conventional materials used as negative electrode active materials for batteries may be used. These negative electrode active materials may be used individually or in combination of two or more.

[0078] In some embodiments, the negative electrode coating layer preferably further comprises an adhesive. The adhesive may be at least one selected from styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethyl methacrylate (PMAA), and carboxymethyl chitosan (CMCS).

[0079] In some embodiments, the negative electrode coating layer preferably further comprises a conductive agent. The conductive agent may be at least one selected from superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0080] In some embodiments, the negative electrode coating layer preferably further comprises other additives such as a thickening agent (e.g., sodium carboxymethylcellulose (CMC-Na)).

[0081] In some embodiments, the negative electrode plate may be manufactured by dispersing the above-mentioned components for manufacturing the negative electrode plate, such as a negative electrode active material, a conductive agent, and an adhesive, and any other components in a solvent (e.g., deionized water) to form a negative electrode slurry, applying the negative electrode slurry to a negative electrode current collector, and obtaining the negative electrode plate by performing processes such as drying and cold pressing.

[0082] [Separator] This application does not particularly limit the type of separator, and any known porous separator with excellent chemical and mechanical stability can be selected.

[0083] In some embodiments, the material of the separator may be at least one selected from glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer thin film or a multilayer composite thin film, and is not particularly limited. If the separator is a multilayer composite thin film, the materials of each layer may be the same or different, and are not particularly limited.

[0084] In some embodiments, the positive electrode plate, negative electrode plate, and separator can be formed into an electrode assembly by a winding process or a lamination process.

[0085] [Secondary battery] A second aspect of the present application provides a secondary battery containing the electrolyte according to the first aspect of the present application.

[0086] Typically, a rechargeable battery includes a positive electrode plate, a negative electrode plate, an electrolyte, and a separator. During the charging and discharging process of the battery, active ions are inserted and removed by moving back and forth between the positive and negative electrode plates. The electrolyte plays a role in conducting ions between the positive and negative electrode plates. The separator is interposed between the positive and negative electrode plates and primarily serves to prevent short circuits between the positive and negative electrodes, while allowing ions to pass through.

[0087] In some embodiments, preferably, the maximum usable voltage of the secondary battery satisfies 4.25 ≤ V ≤ 4.95. In the case of a spinel LNMO system, its charge cutoff voltage is a maximum of 4.95 V.

[0088] In some embodiments, the secondary battery may include an outer casing. This casing may be used to seal and package the electrode assembly and electrolyte.

[0089] In some embodiments, the casing of the secondary battery may be a hard case, such as a rigid plastic case, an aluminum case, or a steel case. The casing of the secondary battery may also be a soft pack, such as a pouch soft pack. The material of the soft pack may be plastic, and examples of plastics include polypropylene, polybutylene terephthalate, and polybutylene succinate.

[0090] Furthermore, the secondary battery, battery module, battery pack, and power consumption device of this application will be described below with reference to the drawings as appropriate.

[0091] This application does not particularly limit the shape of the secondary battery, and it may be cylindrical, rectangular, or any other shape. For example, Figure 1 shows a rectangular secondary battery 5 as an example.

[0092] In some embodiments, referring to Figure 2, the exterior may include a housing 51 and a cover plate 53. The housing 51 may include a bottom plate and side plates connected to the bottom plate, the bottom plate and side plates defining a housing cavity. The housing 51 has an opening that communicates with the housing cavity, and the cover plate 53 can cover the opening to seal the housing cavity. The positive electrode plate, negative electrode plate and separator can be formed into an electrode assembly 52 by a winding or lamination process. The electrode assembly 52 is packaged within the housing cavity. The electrolyte is impregnated into the electrode assembly 52. ​​The number of electrode assemblies 52 included in the secondary battery 5 may be one or more, and those skilled in the art can select according to their specific practical needs.

[0093] In some embodiments, the secondary batteries may be assembled into a battery module, and the number of secondary batteries included in the battery module may be one or more, the specific number of which can be selected by those skilled in the art depending on the application and capacity of the battery module.

[0094] Figure 3 shows an example of a battery module 4. Referring to Figure 3, in the battery module 4, multiple secondary batteries 5 may be arranged sequentially along the length of the battery module 4. Of course, they may be arranged in any other manner. Furthermore, the multiple secondary batteries 5 can be secured with fasteners.

[0095] Preferably, the battery module 4 may further include a casing having a housing space, in which a plurality of secondary batteries 5 are housed.

[0096] In some embodiments, the battery modules may be further assembled into a battery pack, the number of battery modules included in the battery pack may be one or more, and the specific number can be selected by those skilled in the art depending on the application and capacity of the battery pack.

[0097] Figures 4 and 5 show an example of a battery pack 1. Referring to Figures 4 and 5, the battery pack 1 may include a battery housing and a plurality of battery modules 4 installed in the battery housing. The battery housing includes an upper housing 2 and a lower housing 3, and the upper housing 2 is covered by the lower housing 3 and can form a sealed space for housing the battery modules 4. The plurality of battery modules 4 may be arranged in the battery housing in any manner.

[0098] The present application further provides a power consumption device comprising at least one of the secondary battery, battery module, or battery pack relating to the present application. The secondary battery, battery module, or battery pack may be used as a power source for the power consumption device or as an energy storage unit for the power consumption device. The power consumption device may include, but is not limited to, mobile devices (e.g., mobile phones, laptops, etc.), electric vehicles (e.g., pure electric vehicles, hybrid vehicles, plug-in hybrid vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), trains, ships and satellites, energy storage systems, etc.

[0099] The aforementioned power consumption device may be a secondary battery, a battery module, or a battery pack, depending on the needs of its use.

[0100] Figure 6 shows an example of a power consumption device. This power consumption device may be a pure electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. To meet the high power and high energy density needs of the secondary battery of this power consumption device, a battery pack or battery module may be used.

[0101] Another example of such a device may be a mobile phone, tablet PC, or laptop computer. Since such a device typically requires a lighter and thinner design, a rechargeable battery can be used as its power source. [Examples]

[0102] Examples of the present application are described below. The examples described below are illustrative and are for interpretive purposes only, and should not be understood as limiting the present application. Where no specific technical or technical conditions are shown in the examples, they are carried out in accordance with the technical or technical conditions or product instructions described in the literature of the art. Unless the manufacturer is indicated, the reagents or equipment used are all common products available on the market.

[0103] [Example 1] <Manufacturing of positive electrode plates> LiNi 0.6 Co 0.2 Mn 0.2 O2(NCM 622 Acetylene black as a conductive agent and polyvinylidene fluoride (PVDF) as an adhesive were dissolved in the solvent N-methylpyrrolidone (NMP) in a mass ratio of 96.5:1.5:2, and the mixture was thoroughly stirred to obtain a positive electrode slurry. Subsequently, the positive electrode slurry was uniformly applied to the positive electrode current collector, dried, cold-pressed, and cut to obtain a positive electrode plate.

[0104] <Manufacturing of negative electrode plates> Artificial graphite as the active material, acetylene black as the conductive agent, styrene-butadiene rubber (SBR) as the adhesive, and sodium carboxymethylcellulose (CMC) as the thickener were dissolved in solvent-deionized water in a mass ratio of 95:2:2:1. The mixture was then uniformly mixed with the solvent-deionized water to produce a negative electrode slurry. Next, the negative electrode slurry was uniformly applied to the copper foil of the negative electrode current collector, dried to obtain a negative electrode sheet, and then cold-pressed and cut to obtain a negative electrode plate.

[0105] <Manufacturing of electrolyte solution> In a glove box under an argon atmosphere (H2O < 0.1 ppm, O2 < 0.1 ppm), organic solvents were uniformly mixed in mass ratio as shown in Table 1, the salts and additives shown in the table were added, and the mixture was uniformly stirred to obtain a suitable electrolyte.

[0106] <Manufacturing of secondary batteries> Using a 12 μm thick polypropylene film as a separator, the positive electrode plate, separator, and negative electrode plate were stacked in order, with the separator positioned between the positive and negative electrode plates to serve as a separator. The electrode assembly was then placed in a battery case, dried, and electrolyte was injected. A secondary battery was obtained through processes such as formation and settling.

[0107] Table 1 shows the condition parameters for other examples and comparative examples. The processes for manufacturing the positive electrode plate, negative electrode plate, electrolyte, and battery in these examples and comparative examples were the same as those in Example 1.

[0108] <Related parameter tests> 1. 45°C cycle of lithium-ion batteries The cells were placed on three steel plate jigs, and then pressure sensors were connected to detect the expansion force of the cells during the cycle. At 45°C, the lithium-ion battery was charged to 4.4V with a constant current of 1C, then charged again with a constant voltage of 4.4V so that the current was less than 0.05C, and then discharged to 2.8V with a constant current of 1C. This constitutes one charge-discharge cycle. This charging and discharging cycle was repeated for 500 cycles, and the maximum expansion force of the cells during the 500th charging cycle was recorded.

[0109] 2. Test of electrode plate thickness At 25°C, a lithium-ion battery and a lithium-ion battery after 500 cycles at 45°C were both charged to 4.4V with a constant current of 0.33C. Next, they were charged at a constant voltage of 4.4V with a current less than 0.05C. Then the batteries were disassembled, and the thickness of the corresponding positive electrode plates was measured with a micrometer. After 10 measurements and taking the average value, the thickness of the positive electrode plate of the lithium-ion battery was h1, and the thickness of the positive electrode plate of the lithium-ion battery after 45°C EOL cycles was h2. The increase rate of the corresponding positive electrode plate thickness is (h2-h1) / h1.

[0110] [Table 1]

[0111] By comprehensively analyzing Examples E1-E6 and Comparative Examples C1-C3 in Table 1, it was found that the plate expansion and cycle stress of the secondary batteries corresponding to Examples E1-E6 were significantly lower than those of Comparative Examples C1-C3.

[0112] By comparing Comparative Examples C4-C5 with Examples E1-E5, it was found that when the molar ratio of titanate ester to fluorine-containing metal salt was 2 / 1 to 1 / 20, the expansion and cycle stress of the secondary battery electrode plates were superior.

[0113] Examples E7 to E8 showed that when the electrolyte contains a fluorinated solvent, the expansion and cycle stress of the electrode plates of the secondary battery are further optimized.

[0114] <Influence of adhesive in the positive electrode coating layer on battery performance> In Example E9 of the present invention, the adhesive PVDF-Ac was added to the manufacturing process of the positive electrode plate. PVDF-Ac was manufactured by an emulsion polymerization method, and was produced in the same manner as in Example E2, except that the molar ratio of vinylidene fluoride, ethylene, methyl acrylate monomer, and acrylic acid monomer used in the synthesis was 60:10:25:5.

[0115] Polymerization method Deionized water, a dispersant, a pH adjuster, and a chain transfer agent were added to a stainless steel reaction vessel, deoxidized under vacuum, a predetermined amount of acrylic acid ester, acrylic acid monomer, and half of the required vinylidene fluoride were added, an initiator was added, the temperature and pressure were controlled, and the polymerization reaction was started. The remaining half of vinylidene fluoride and ethylene were added sequentially, and when polymerization was complete, the polymer was dissolved, washed, and dried to obtain the PVdF-Ac product, which had a molecular weight of 900,000.

[0116] [Table 2]

[0117] Table 2 shows that when the positive electrode coating layer contains vinylidene fluoride-alkyl unit-acrylate-acrylic acid copolymer (PVdF-Ac) as an adhesive, the secondary battery exhibits reduced electrode plate expansion and lower cycle stress.

[0118] <Influence of additives in the negative electrode coating layer on battery performance> In Examples E10-E11 of this application, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane or diphenylmethane diisocyanate was added as a negative electrode additive during the manufacturing of the negative electrode plate. As shown in Table 3, artificial graphite was used as the active material, acetylene black as the conductive agent, styrene-butadiene rubber (SBR) as the adhesive, sodium carboxymethylcellulose (CMC) as the thickener, and the negative electrode additive was dissolved in solvent-deionized water in a mass ratio of 95:2:2:0.8:0.2, and the negative electrode slurry was produced by uniformly mixing it with the solvent-deionized water. Otherwise, the method was the same as in Example E2.

[0119] [Table 3]

[0120] Table 3 shows that when the negative electrode coating layer contains 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane or diphenylmethane diisocyanate, the secondary battery exhibits reduced electrode plate expansion and lower cycle stress.

[0121] <Battery performance at various voltages> Comparative Example C6 of the present invention was manufactured in the same manner as Comparative Example C1, except that the charge cutoff voltage was set to 4.2V in the test of the secondary battery of Comparative Example C6. Example E12 of the present invention was manufactured in the same manner as Example E2, except that the charge cutoff voltage was set to 4.2V in the test of the secondary battery of Example E12.

[0122] [Table 4]

[0123] Furthermore, this application is not limited to the embodiments described above. The embodiments described above are merely examples, and any embodiment that has substantially the same configuration as the technical idea and exhibits the same effects within the scope of the technical proposal of this application is included within the scope of the technical application. In addition, any other form that combines some of the components of an embodiment, made by various modifications to an embodiment that a person skilled in the art could conceive of, without departing from the gist of this application, is also included within the scope of this application. [Explanation of symbols]

[0124] 1. Battery pack 2. Upper cabinet 3. Lower cabinet 4. Battery Module 5... Secondary battery 51. Housing 52...electrode assembly 53. Top cover assembly

Claims

1. A secondary battery containing an electrolyte, wherein the electrolyte is A fluorine-containing metal salt selected from lithium salts containing P=O, Titanic acid ester having a structural formula of Ti-(O-R １ ), ４ wherein the R １ is one or more selected from a C １ -C ６ alkyl group, a C １ -C ６ haloalkyl group, a C ２ -C ６ alkenyl group, a C ２ -C ６ alkynyl group or a C １ -C ６ silane group, and the titanic acid ester Includes, A secondary battery wherein the fluorine-containing metal salt accounts for 0.01% to 8% of the electrolyte mass, and the titanate ester accounts for 0.01% to 8% of the electrolyte mass.

2. The titan ester is, 【Chemistry 1】 The secondary battery according to claim 1, wherein it is one or more types selected from the following.

3. The secondary battery according to claim 1 or 2, wherein the molar ratio of the titanate ester to the fluorine-containing metal salt is 2 / 1 to 1 / 20.

4. The secondary battery according to any one of claims 1 to 3, wherein the fluorine-containing metal salt accounts for 0.1% to 5% of the electrolyte mass.

5. The secondary battery according to any one of claims 1 to 4, wherein the titanate ester accounts for 0.1% to 5% of the electrolyte mass.

6. The secondary battery according to any one of claims 1 to 5, wherein the total of the fluorine-containing metal salt and the titanate ester accounts for 0.01 to 10% of the electrolyte mass.

7. The electrolyte further comprises a fluorinated solvent, The secondary battery according to any one of claims 1 to 6, wherein the fluorinating solvent is one or more selected from fluorocarbonates, fluorobenzenes, and fluoroethers.

8. The aforementioned fluorocarbonate is 【Chemistry 2】 At least one selected from and / or The aforementioned fluorobenzene is 【Transformation 3】 and / or, The aforementioned fluoroether is 【Chemistry 4】 And, In the formula, R ２ , R ３ , R ４ , R ５ Each of them is independent of C １ -C ６ alkyl group, C １ -C ６ Selected from fluoroalkyl groups, R ６ , R ７ Each of them is independent of C １ -C ４ Alkylene group, C １ -C ４ Selected from fluoroalkylene groups, R ８ , R ９ , R １０ , R １１ , R １２ , R １３ The secondary battery according to claim 7, wherein each is independently selected from F or H.

9. The aforementioned fluorocarbonate is 【Transformation 5】 At least one selected from and / or The aforementioned fluorobenzene is 【Transformation 6】 and / or, The aforementioned fluoroether is 【Transformation 7】 The secondary battery according to claim 7 or 8, wherein it is at least one selected from the following.

10. The secondary battery according to any one of claims 7 to 9, wherein the fluorinated solvent accounts for 10 to 70% of the electrolyte mass.

11. The aforementioned secondary battery includes a positive electrode plate and a negative electrode plate, The positive electrode plate includes a positive electrode current collector and a positive electrode coating layer provided on at least one surface of the positive electrode current collector. The secondary battery according to any one of claims 1 to 10, wherein the positive electrode coating layer contains a vinylidene fluoride-alkyl unit-acrylate-acrylic acid copolymer (PVdF-Ac) as an adhesive.

12. The adhesive is of general formula (I): 【Transformation 8】 (In the formula, m = 60% to 75%, n = 5% to 10%, x = 10% to 25%, y = 3% to 5%, m + n + x + y = 100%, R １ ', R ２ ', R ３ ', R ４ 'Each of these is independently a hydrogen atom, or a C atom that may be substituted. １ -C ８ The alkyl group is selected, and the substituent is at least one selected from F, Cl, and Br. R ５ ', R ６ ', R ７ 'Each of these is independently a hydrogen atom, or a C atom that may be substituted. １ -C ６ The alkyl group is selected, and the substituent is at least one selected from F, Cl, and Br. R ８ ' may be replaced by C １ -C １５ The alkyl group is selected, and the substituent is at least one selected from F, Cl, and Br. R ９ ', R １０ ', R １１ 'Each of these is independently a hydrogen atom, or a C atom that may be substituted. １ -C ６ The secondary battery according to claim 11, having a structure selected from alkyl groups, wherein the substituent is at least one selected from F, Cl, and Br.

13. The secondary battery according to claim 11, wherein the positive electrode coating layer contains at least one positive electrode active material selected from lithium iron manganese phosphate, lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and composites of these compounds with other transition metals or non-transition metals.

14. The negative electrode plate includes a negative electrode current collector and a negative electrode coating layer installed on at least one surface of the negative electrode current collector. The negative electrode coating layer contains a compound having an epoxy group or an isocyanate group, If the negative electrode coating layer contains a compound having epoxy groups, the compound having epoxy groups contains at least two epoxy groups. The secondary battery according to claim 11, wherein the negative electrode coating layer contains a compound having an isocyanate group, and the compound having an isocyanate group contains at least two isocyanate groups.

15. The epoxy group-containing compound is one or more selected from bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol S diglycidyl ether, pentaerythritol tetraglycidyl ether, 1,4-butanediol diglycidyl ether, propylene glycol glycidyl ether, glycidyl phthalate, tetrahydrophthalate diglycidyl, 1,2-cyclohexanedicarboxylate diglycidyl, 4,4'-tetraglycidyldiaminodiphenylmethane epoxy, triglycidyl p-aminophenol, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, tetraglycidyl-1,3-bis(aminomethylcyclohexane), 9,9-bis[(2,3-glycidoxy)phenyl]fluorene, 1,4-cyclohexanedimethanol diglycidyl ether, tetraglycidyl-4,4'-diaminodiphenyl ether, and tetraglycidyl-3,4'-diaminodiphenyl ether. The secondary battery according to claim 14, wherein the compound having the isocyanate group is one or more selected from toluene diisocyanate, diphenylmethane diisocyanate, 1,5-naphthalene diisocyanate, dimethylbiphenyl diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexane diisocyanate, 1,4-phenylene diisocyanate, and norbornene diisocyanate.

16. A power consumption device comprising a secondary battery according to any one of claims 1 to 15.

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