Nonaqueous electrolyte solution and nonaqueous electrolyte battery using same

Abstract

The present disclosure provides: a nonaqueous electrolyte solution containing (I) at least one sulfonic acid anhydride represented by general formula (1) set forth in the description, (II) at least one compound selected from the group represented by "2", "3", "4", "5", "6", and "7" set forth in the description, (III) a solute, and (IV) a nonaqueous organic solvent; and a nonaqueous electrolyte battery including at least a positive electrode, a negative electrode, a separator, and said nonaqueous electrolyte solution.

Description

Nonaqueous electrolyte and nonaqueous electrolyte battery using the same

[0001] The present invention relates to a nonaqueous electrolyte and a nonaqueous electrolyte battery using the same.

[0002] To date, optimization of various battery components, including the active materials of the positive and negative electrodes, has been investigated as a means of improving the cycle characteristics, high-temperature storage characteristics, and durability of non-aqueous electrolyte batteries. Non-aqueous electrolyte-related technologies are no exception, and various additives have been proposed to suppress degradation caused by decomposition of the non-aqueous electrolyte on the surfaces of the active positive and negative electrodes.

[0003] For example, Patent Document 1 proposes improving cycle characteristics by using sulfonic acid anhydride in an electrolyte. Patent Document 2 proposes improving cycle characteristics and low-temperature characteristics by using a silicon compound in an electrolyte. Patent Document 3 proposes improving storage characteristics by using a nonaqueous electrolyte containing lithium bisfluorosulfonylimide as a solute. Patent Document 4 proposes improving storage characteristics after charging by using lithium monofluorophosphate or lithium difluorophosphate in an electrolyte. Patent Document 5 proposes maintaining high input / output characteristics and impedance characteristics even after durability testing by using a nonaqueous electrolyte containing a fluorosulfonate. Patent Document 6 proposes suppressing decomposition on a carbon anode as the charge / discharge cycle progresses by using a nonaqueous electrolyte containing a cyclic sulfate ester. Patent Document 7 proposes significantly suppressing deterioration in load characteristics and resistance and producing a battery with reduced gas generation within the battery by using a nonaqueous electrolyte containing a cyclic sultone (unsaturated sultone). Patent Document 8 discloses electrolytes containing various oxalate salts and malonate salts, which have high heat resistance and hydrolysis resistance. Patent Document 9 also discloses that a nonaqueous electrolyte battery having high durability at high temperatures can be obtained by adding a picolinic acid derivative represented by general formula (3) in the patent document to a nonaqueous electrolyte.

[0004] Japanese Patent No. 3760539 Japanese Patent No. 3497812 Japanese Patent No. 4847675 Japanese Patent No. 3439085 Japanese Patent No. 5353923 Japanese Patent No. 3760540 Japanese Patent No. 4190162 Japanese Patent No. 3722685 WO-A1-2016 / 002774

[0005] However, the inventors of the present invention have conducted research and found that although the batteries disclosed in the prior art documents certainly have improved battery characteristics, there is still room for improvement in terms of initial resistance.

[0006] The present disclosure has been made in view of the above circumstances, and an object of the present disclosure is to provide a nonaqueous electrolyte and a nonaqueous electrolyte battery that can reduce the initial resistance value of a battery.

[0007] As a result of intensive research into solving these problems, the present inventors have found that by incorporating a specific sulfonic acid anhydride and at least one compound selected from the group consisting of phosphates, sulfonates, imide salts, borates, picolinic acid derivatives, silicon compounds, cyclic sulfates, and cyclic sultones, which have specific structures, into a nonaqueous electrolyte solution for nonaqueous electrolyte batteries, the initial resistance of the battery can be reduced when the electrolyte solution is used in the battery, thereby completing the present invention.

[0008] That is, the present invention is as follows: [1] A non-aqueous electrolyte solution containing: (I) at least one sulfonic acid anhydride "1" represented by the following general formula (1), (II) at least one compound selected from the group represented by the following "2", "3", "4", "5", "6", and "7", (III) a solute, and (IV) a non-aqueous organic solvent.

[0009]

[0010] In general formula (1), R １ and R ２ R each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkenyl group having 2 to 10 carbon atoms, or an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms. １ and R２ Any hydrogen atom in the alkyl group, alkenyl group, and aryl group represented by the formula (2) may be substituted with a halogen atom. The formula (2) represents at least one compound selected from the group consisting of compounds represented by the following general formulas (2-1) and (2-2):

[0011]

[0012] In general formula (2-1), R ３ and R ４ are each independently a fluorine atom, or an organic group selected from a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may also contain a fluorine atom, an oxygen atom, or an unsaturated bond. In addition, general formula (2-1) contains at least one P-F bond. In general formula (2-2), X １ is a fluorine atom, or an organic group selected from a linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may contain at least one fluorine atom, and the organic group may also contain an oxygen atom or an unsaturated bond. １ ｍ＋ is a proton, a metal cation, or an onium cation. m represents the valence of the corresponding cation. The "3" is at least one compound selected from the group consisting of compounds represented by the following general formulas (3-1) to (3-3):

[0013]

[0014] In general formulas (3-1) to (3-3), R ５ ~R １０ are each independently a fluorine atom or an organic group selected from a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may contain a fluorine atom, an oxygen atom, or an unsaturated bond. ２ ~X ４ are each independently a fluorine atom, or an organic group selected from a linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may also contain a fluorine atom, an oxygen atom, or an unsaturated bond. Furthermore, general formulas (3-1) to (3-3) each contain at least one P-F bond and / or S-F bond. M １ ｍ＋ is a proton, a metal cation, or an onium cation. m represents the valence of the corresponding cation. The "4" is at least one compound selected from the group consisting of compounds represented by the following general formula (4-1) and compounds represented by the following general formula (4-2):

[0015]

[0016] In the general formula (4-1), W represents a boron atom, a phosphorus atom, or a silicon atom, n1 represents an integer of 0 to 3, n2 represents an integer of 0 to 4, and p represents an integer of 0 or 1. ４１represents an alkylene group having 1 to 10 carbon atoms, a halogenated alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a halogenated arylene group having 6 to 20 carbon atoms (these groups may contain a substituent or a heteroatom in the structure. When n1 is 2 or more, n1 R ４１ may be bonded to each other), and R ４２ represents a halogen atom, and Y １ , Y ２ each independently represents an oxygen atom or a sulfur atom; Y ３ represents a carbon atom or a sulfur atom. ３ is 1 when it is a carbon atom, and 1 or 2 when it is a sulfur atom. ａ＋ represents an alkali metal cation, an alkaline earth metal cation, or an onium cation, a represents the valence of the corresponding cation, and a to d are 1 or 2, and a×b=c×d is satisfied.

[0017]

[0018] In general formula (4-2), R ４３ represents an alkylene group having 1 to 10 carbon atoms, a halogenated alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a halogenated arylene group having 6 to 20 carbon atoms (these groups may contain a substituent or a heteroatom in the structure), and r is 0 or 1. Y ４ represents a carbon atom or a sulfur atom. ４ is 1 when it is a carbon atom, and 1 or 2 when it is a sulfur atom. ２ represents a boron atom or a phosphorus atom, R ４４ represents a halogen atom. n3 represents W ２ is 2 when it is a boron atom, and is 4 when it is a phosphorus atom. The "5" is at least one compound represented by the following general formula (5):

[0019]

[0020] In general formula (5), R ５１ R each independently represents a group having a carbon-carbon unsaturated bond. ５２When there are a plurality of "a" and "b", each independently represents a fluorine atom or a linear or branched alkyl group having 1 to 10 carbon atoms, and the alkyl group may have at least one of a fluorine atom and an oxygen atom. "v" represents an integer of 2 to 4. "6" represents at least one compound represented by the following general formula (6),

[0021]

[0022] In general formula (6), R ６１ and R ６２ R each independently represents a hydrogen atom, an alkyl group having 1 to 2 carbon atoms, a linear or branched alkenyl group having 2 to 5 carbon atoms, or an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms. ６１ and R ６２ Any hydrogen atom in the alkyl group, alkenyl group, and aryl group represented by the formula (7) may be substituted with a halogen atom. n6 is 0 or 1. The formula "7" is at least one compound selected from the group consisting of compounds represented by the following general formulas (7-1) and (7-2).

[0023]

[0024] In general formula (7-1), R ７０ ~R ７３ each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, or a fluoroalkyl group having 1 to 4 carbon atoms. n71 represents an integer of 1 to 3. In general formula (7-2), R ７４ ~R ７９ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a fluoroalkyl group having 1 to 4 carbon atoms. n72 represents an integer of 0 to 2.

[0025] [2] The nonaqueous electrolyte solution according to [1], wherein the content of (I) is 0.01% by mass to 10% by mass relative to the total amount of the nonaqueous electrolyte solution. [3] The nonaqueous electrolyte solution according to [1] or [2], wherein the content of (II) is 0.01% by mass to 10% by mass relative to the total amount of the nonaqueous electrolyte solution. [4] The nonaqueous electrolyte solution according to any one of [1] to [3], wherein (I) is at least one compound selected from the group consisting of methanesulfonic anhydride and ethanesulfonic anhydride. [5] The nonaqueous electrolyte solution according to any one of [1] to [4], wherein "2" is at least one compound selected from the group consisting of lithium difluorophosphate, lithium fluorosulfonate, and lithium trifluoromethanesulfonate. [6] The non-aqueous electrolyte solution according to any one of [1] to [5], wherein the "3" is at least one compound selected from the group consisting of bis(fluorosulfonyl)imide lithium, (fluorosulfonyl)(difluorophosphoryl)imide lithium, bis(trifluoromethanesulfonyl)imide lithium, bis(difluorophosphoryl)imide lithium, bis(pentafluoroethanesulfonyl)imide lithium, and (fluorosulfonyl)(trifluoromethanesulfonyl)imide lithium. [7] The non-aqueous electrolyte solution according to any one of [1] to [6], wherein the "4" is at least one compound selected from the group consisting of lithium tetrafluoroborate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium tris(oxalato)phosphate, lithium difluorobis(oxalato)phosphate, lithium tetrafluoro(oxalato)phosphate, lithium difluoro(malonato)borate, lithium tetrafluoro(malonato)phosphate, tetrafluoro(picolinato)phosphate, and difluoro(picolinato)borate. [8] The non-aqueous electrolyte solution according to any one of [1] to [7], wherein the "5" is at least one compound selected from the group consisting of trivinylmethylsilane, trivinylfluorosilane, and tetravinylsilane.[9] The nonaqueous electrolyte solution according to any one of [1] to [8], wherein the "6" is at least one compound selected from the group consisting of 1,3,2-dioxathiolane-2,2-dioxide and 1,3,2-dioxathiane-2,2-dioxide.

[10] The (III) is LiPF. ６ , LiSbF ６ , LiAsF ６ , LiClO ４ , LiAlO ２ , LiAlCl ４ , LiCl, and LiI, or NaPF ６ , NaSbF ６ , NaAsF ６ , NaClO ４ , NaAlO ２ , NaAlCl ４ , NaCl, and NaI.

[11] The nonaqueous electrolyte solution according to any one of [1] to

[10] , wherein (IV) includes at least one selected from the group consisting of a cyclic ester, a chain ester, a cyclic ether, a chain ether, a sulfone compound, a sulfoxide compound, and an ionic liquid.

[12] The nonaqueous electrolyte solution according to

[11] , wherein the cyclic ester is a cyclic carbonate, and the cyclic carbonate is at least one selected from the group consisting of ethylene carbonate, propylene carbonate, and fluoroethylene carbonate.

[13] The nonaqueous electrolyte solution according to

[11] , wherein the chain ester is a chain carbonate, and the chain carbonate is at least one selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, and methyl propyl carbonate.

[14] A non-aqueous electrolyte battery comprising at least a positive electrode, a negative electrode, a separator, and the non-aqueous electrolyte according to any one of [1] to

[13] .

[0026] The present disclosure provides a nonaqueous electrolyte and a nonaqueous electrolyte battery that can reduce the initial resistance value of a battery.

[0027] The configurations and combinations thereof in the following embodiments are examples, and additions, substitutions, and other modifications of the configurations are possible without departing from the spirit of the present disclosure. Furthermore, the present disclosure is not limited to the embodiments, but is limited only by the claims.

[0028] In this specification, the word "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit.

[0029] [1. Nonaqueous Electrolyte] The nonaqueous electrolyte of the present disclosure is a nonaqueous electrolyte containing: (I) at least one sulfonic acid anhydride "1" represented by the above general formula (1); (II) at least one compound selected from the group represented by the above "2," "3," "4," "5," "6," and "7"; (III) a solute; and (IV) a nonaqueous organic solvent.

[0030] When a nonaqueous electrolyte containing both component (I) and component (II) is used in a nonaqueous electrolyte battery (e.g., a lithium-ion secondary battery or a sodium-ion secondary battery), components (I) and (II) decompose on at least one of the positive electrode and the negative electrode, forming a coating with high cation conductivity on at least one of the positive electrode and the negative electrode. This coating is thought to suppress direct contact between the nonaqueous organic solvent or the solute and the electrode active material, thereby reducing the cation dissociation energy of the solute. The inventors believe that this results in a reduction in the initial resistance of the nonaqueous electrolyte battery.

[0031] [Regarding Component (I)] The non-aqueous electrolyte solution of the present disclosure contains at least one sulfonic acid anhydride "1" represented by general formula (1), which is component (I).

[0032]

[0033] In general formula (1), R １ and R ２ R each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkenyl group having 2 to 10 carbon atoms, or an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms. １ and R ２Any hydrogen atom in the alkyl group, alkenyl group, or aryl group represented by the formula (I) may be substituted with a halogen atom.

[0034] R １ and R ２ When R is a linear or branched alkyl group having 1 to 6 carbon atoms, examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group. １ and R ２ However, when R is a linear or branched alkenyl group having 2 to 10 carbon atoms, examples of the alkenyl group include a vinyl group, an allyl group, a 1-propenyl group, an isopropenyl group, a 2-butenyl group, and a 1,3-butadienyl group. １ and R ２ However, when the aryl group is an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms, examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, etc. The number of carbon atoms of 6 to 10 refers to the total number of carbon atoms in the aryl group and, when the aryl group is substituted with an alkyl group, the total number of carbon atoms in the alkyl group.

[0035] At least one of the hydrogen atoms in the alkyl group, alkenyl group, and aryl group may be substituted with a halogen atom, such as a fluorine atom, a bromine atom, or an iodine atom, with a fluorine atom being preferred.

[0036] R １ and R ２ are each independently preferably a linear or branched alkyl group having 1 to 6 carbon atoms, more preferably a methyl group, an ethyl group, or an isopropyl group, and even more preferably a methyl group or an ethyl group.

[0037] R １ and R ２ It is particularly preferred that all of the groups represent a methyl group or all of the groups represent an ethyl group. That is, it is preferred that component (I) is at least one selected from the group consisting of methanesulfonic anhydride and ethanesulfonic anhydride.

[0038] Specific examples of the sulfonic acid anhydride represented by formula (1) are shown below, but the invention is not limited thereto.

[0039]

[0040] In the nonaqueous electrolyte solution of the present disclosure, the content of the component (I) (hereinafter also referred to as the "concentration of (I)") relative to the total amount (100% by mass) of the nonaqueous electrolyte solution may have a lower limit of 0.01% by mass or more, 0.05% by mass or more, or 0.1% by mass or more. The upper limit of the concentration of (I) may be 10% by mass or less, 5% by mass or less, 4% by mass or less, or 2.5% by mass or less. By setting the concentration of (I) to 0.01% by mass or more, the effect of suppressing an increase in the initial resistance of a nonaqueous electrolyte battery using the nonaqueous electrolyte solution and the effect of improving the cycle characteristics can be easily obtained. On the other hand, by setting the concentration of (I) to 10% by mass or less, the increase in viscosity of the nonaqueous electrolyte solution can be suppressed, and the effect of suppressing an increase in the initial resistance of a nonaqueous electrolyte battery using the nonaqueous electrolyte solution can be easily obtained. The content of the component (I) relative to the total amount of the non-aqueous electrolyte is preferably 0.01 to 10% by mass, more preferably 0.01 to 5% by mass.

[0041] In the nonaqueous electrolyte solution of the present disclosure, as component (I), one type of compound may be used alone, or two or more types of compounds may be mixed in any combination and ratio depending on the application.

[0042] The sulfonic acid anhydride represented by the general formula (1) can be produced by a known method.

[0043] [Regarding Component (II)] The nonaqueous electrolyte solution of the present disclosure contains, as component (II), at least one compound selected from the group represented by "2," "3," "4," "5," "6," and "7" below.

[0044] <"2"> "2" is at least one compound selected from the group consisting of compounds represented by the following general formulas (2-1) and (2-2).

[0045]

[0046] In general formula (2-1), R ３ and R ４ are each independently a fluorine atom, or an organic group selected from a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may also contain a fluorine atom, an oxygen atom, or an unsaturated bond. In addition, general formula (2-1) contains at least one P-F bond. In general formula (2-2), X １ is a fluorine atom, or an organic group selected from a linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may contain at least one fluorine atom, and the organic group may also contain an oxygen atom or an unsaturated bond. １ ｍ＋ is a proton, a metal cation or an onium cation, and m represents the valence of the corresponding cation.

[0047] In general formula (2-1), R ３ and R ４Examples of the alkoxy group represented by the formula (I) include alkoxy groups having 1 to 10 carbon atoms and fluorine-containing alkoxy groups, such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a sec-butoxy group, a tert-butoxy group, a pentyloxy group, a trifluoromethoxy group, a 2,2-difluoroethoxy group, a 2,2,2-trifluoroethoxy group, a 2,2,3,3-tetrafluoropropoxy group, a 1,1,1-trifluoroisopropoxy group, and a 1,1,1,3,3,3-hexafluoroisopropoxy group. R ３ and R ４ Examples of the alkenyloxy group represented by the formula (R) include alkenyloxy groups having 2 to 10 carbon atoms and fluorine-containing alkenyloxy groups, such as vinyloxy group, 1-propenyloxy group, 2-propenyloxy group, isopropenyloxy group, 2-butenyloxy group, 3-butenyloxy group, and 1,3-butadienyloxy group. ３ and R ４ Examples of the alkynyloxy group represented by the formula (R) include alkynyloxy groups having 2 to 10 carbon atoms, such as an ethynyloxy group, a 2-propynyloxy group, and a 1,1-dimethyl-2-propynyloxy group, and fluorine-containing alkynyloxy groups. ３ and R ４ Examples of the cycloalkoxy group represented by the formula (R) include cycloalkoxy groups having 3 to 10 carbon atoms, such as a cyclopentyloxy group and a cyclohexyloxy group, and fluorine-containing cycloalkoxy groups. ３ and R ４ Examples of the cycloalkenyloxy group represented by the formula (R) include cycloalkenyloxy groups having 3 to 10 carbon atoms, such as a cyclopentenyloxy group and a cyclohexenyloxy group, and fluorine-containing cycloalkenyloxy groups. ３ and R ４ Examples of the aryloxy group represented by the formula (I) include aryloxy groups having 6 to 10 carbon atoms, such as a phenyloxy group, a tolyloxy group, and a xylyloxy group, and fluorine-containing aryloxy groups.

[0048] R ３ and R ４are each independently a fluorine atom or an alkoxy group having a fluorine atom, which is preferable because the degree of ionic dissociation is improved due to its strong electron-withdrawing property, thereby increasing the ionic conductivity in a solution or a composition. Furthermore, a fluorine atom is even more preferable because the anion size is reduced, which improves mobility, thereby significantly increasing the ionic conductivity in a solution or a composition. ３ and R ４ The number of carbon atoms is preferably 6 or less. When the number of carbon atoms is 6 or less, the ionic conductivity tends to be relatively high, which is preferable.

[0049] In general formula (2-1), M １ ｍ＋ represents a proton, a metal cation, or an onium cation. There are no particular limitations on the type of the cation, and various cations can be selected from the above, as long as they do not impair the performance of the nonaqueous electrolyte and nonaqueous electrolyte battery of the present invention.

[0050] M １ ｍ＋ When M represents a metal cation, examples of the metal cation include alkali metal cations such as lithium ion, sodium ion, potassium ion, rubidium ion, and cesium ion, alkaline earth metal cations such as magnesium ion, calcium ion, and barium ion, silver ion, copper ion, and iron ion. １ ｍ＋ When represents an onium cation, examples of the onium cation include onium cations such as tetraalkylammonium, tetraalkylphosphonium, and imidazolium derivatives.

[0051] M １ ｍ＋ In particular, from the viewpoint of helping ion conduction in a non-aqueous electrolyte battery, lithium ions, sodium ions, potassium ions, tetramethylammonium ions, tetraethylammonium ions, tetrabutylphosphonium ions, etc. are preferred. １ ｍ＋When used in a lithium ion battery, the charge carrier is more preferably a lithium ion, and when used in a sodium ion battery, the charge carrier is more preferably a sodium ion.

[0052] Specific examples of the anion structure of the compound represented by formula (2-1) are shown below, but are not limited to these.

[0053]

[0054] In general formula (2-2), X １ Examples of the alkyl group represented by the formula (X) include alkyl groups having 1 to 10 carbon atoms and fluorine-containing alkyl groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, a pentyl group, a trifluoromethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a 2,2,3,3-tetrafluoropropyl group, and a 1,1,1,3,3,3-hexafluoroisopropyl group. １ Examples of the alkenyl group represented by the formula (X) include alkenyl groups having 2 to 10 carbon atoms and fluorine-containing alkenyl groups, such as vinyl group, 1-propenyl group, 2-propenyl group, isopropenyl group, 2-butenyl group, 3-butenyl group, and 1,3-butadienyl group. １ Examples of the alkynyl group represented by the formula (X) include alkynyl groups having 2 to 10 carbon atoms, such as ethynyl, 2-propynyl, and 1,1-dimethyl-2-propynyl, and fluorine-containing alkynyl groups. １ Examples of the cycloalkyl group represented by the formula (X) include cycloalkyl groups having 3 to 10 carbon atoms, such as a cyclopentyl group and a cyclohexyl group, and fluorine-containing cycloalkyl groups. １ Examples of the cycloalkenyl group represented by X include cycloalkenyl groups having 3 to 10 carbon atoms, such as a cyclopentenyl group and a cyclohexenyl group, and fluorine-containing cycloalkenyl groups; １ Examples of the aryl group represented by X include aryl groups having 6 to 10 carbon atoms, such as a phenyl group, a tolyl group, and a xylyl group, and fluorine-containing aryl groups. １The alkoxy group, alkenyloxy group, alkynyloxy group, cycloalkoxy group, cycloalkenyloxy group, and aryloxy group represented by the formula (2-1) are R ３ and R ４ Examples of the alkoxy group include an alkoxy group, an alkenyloxy group, an alkynyloxy group, a cycloalkoxy group, a cycloalkenyloxy group, and an aryloxy group represented by the following formula:

[0055] In general formula (2-2), X １ is preferably a fluorine atom or an alkyl group containing a fluorine atom, since the degree of ionic dissociation is improved due to its strong electron-withdrawing property, thereby increasing the ionic conductivity in a solution or composition. Furthermore, a fluorine atom is more preferable, since the anion size is reduced, thereby improving the mobility, thereby significantly increasing the ionic conductivity in a solution or composition. １ When the number of carbon atoms is 6 or less, the ionic conductivity tends to be relatively high, so it is preferable, the number of carbon atoms is more preferably 1 to 4, and the number of carbon atoms is still more preferably 1 to 3. Specific examples include a trifluoromethyl group, a trifluoromethoxy group, and a trifluoroethoxy group, and a trifluoromethyl group having a small anion size is particularly preferable.

[0056] In general formula (2-2), M １ ｍ＋ represents M in general formula (2-1). １ ｍ＋ The same applies to preferred examples.

[0057] Specific examples of the anion structure of the compound represented by formula (2-2) are shown below, but are not limited to these.

[0058]

[0059] "2" is preferably at least one compound selected from the group consisting of difluorophosphates, fluorosulfonates, and trifluoromethanesulfonates, and more preferably at least one compound selected from the group consisting of lithium difluorophosphate, lithium fluorosulfonate, and lithium trifluoromethanesulfonate.

[0060] <“3”> “3” is at least one compound selected from the group consisting of compounds represented by the following general formulas (3-1) to (3-3).

[0061]

[0062] In general formulas (3-1) to (3-3), R ５ ~R １０ are each independently a fluorine atom or an organic group selected from a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may contain a fluorine atom, an oxygen atom, or an unsaturated bond. ２ ~X ４ are each independently a fluorine atom, or an organic group selected from a linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may also contain a fluorine atom, an oxygen atom, or an unsaturated bond. Furthermore, general formulas (3-1) to (3-3) each contain at least one P-F bond and / or S-F bond. M １ ｍ＋ is a proton, a metal cation or an onium cation, and m represents the valence of the corresponding cation.

[0063] R ５ ~R １０ The alkoxy group, alkenyloxy group, alkynyloxy group, cycloalkoxy group, cycloalkenyloxy group, and aryloxy group represented by the formula (2-1) are R３ and R ４ Examples of the alkoxy group include an alkoxy group, an alkenyloxy group, an alkynyloxy group, a cycloalkoxy group, a cycloalkenyloxy group, and an aryloxy group represented by the following formula:

[0064] R ５ ~R １０ are each independently a fluorine atom or an alkoxy group having a fluorine atom, which is preferable because the degree of ionic dissociation is improved due to its strong electron-withdrawing property, thereby increasing the ionic conductivity in a solution or a composition. Furthermore, a fluorine atom is even more preferable because the anion size is reduced, which improves mobility, thereby significantly increasing the ionic conductivity in a solution or a composition. ５ ~R １０ The number of carbon atoms is preferably 6 or less. When the number of carbon atoms is 6 or less, the ionic conductivity tends to be relatively high, which is preferable.

[0065] X ２ ~X ４ Examples of the alkyl group, alkenyl group, alkynyl group, cycloalkyl group, cycloalkenyl group, aryl group, alkoxy group, alkenyloxy group, alkynyloxy group, cycloalkoxy group, cycloalkenyloxy group, and aryloxy group represented by the formula (2-1) above include X １ Examples of the alkyl group include an alkyl group, an alkenyl group, an alkynyl group, a cycloalkyl group, a cycloalkenyl group, an aryl group, an alkoxy group, an alkenyloxy group, an alkynyloxy group, a cycloalkoxy group, a cycloalkenyloxy group, and an aryloxy group represented by the following formula:

[0066] X ２ ~X ４ is preferably a fluorine atom or an alkyl group containing a fluorine atom, since the degree of ionic dissociation is improved due to its strong electron-withdrawing property, thereby increasing the ionic conductivity in a solution or composition. Furthermore, a fluorine atom is more preferable, since the anion size is reduced, thereby improving the mobility, thereby significantly increasing the ionic conductivity in a solution or composition. ２ ~X ４When the number of carbon atoms is 6 or less, the ionic conductivity tends to be relatively high, so it is preferable, the number of carbon atoms is more preferably 1 to 4, and the number of carbon atoms is still more preferably 1 to 3. Specific examples include a trifluoromethyl group and a pentafluoroethyl group, and a trifluoromethyl group having a small anion size is particularly preferable.

[0067] In general formulas (3-1) to (3-3), M １ ｍ＋ represents M in general formula (2-1). １ ｍ＋ The same applies to preferred examples.

[0068] Specific examples of the anion structures of the compounds represented by general formulas (3-1) to (3-3) are shown below, but are not limited to these.

[0069]

[0070]

[0071]

[0072] "3" is preferably at least one compound selected from the group consisting of bis(fluorosulfonyl)imide salts, (fluorosulfonyl)(difluorophosphoryl)imide salts, bis(trifluoromethanesulfonyl)imide salts, bis(difluorophosphoryl)imide salts, bis(pentafluoroethanesulfonyl)imide salts, and (fluorosulfonyl)(trifluoromethanesulfonyl)imide salts, and more preferably at least one compound selected from the group consisting of bis(fluorosulfonyl)imide lithium, (fluorosulfonyl)(difluorophosphoryl)imide lithium, bis(trifluoromethanesulfonyl)imide lithium, bis(difluorophosphoryl)imide lithium, bis(pentafluoroethanesulfonyl)imide lithium, and (fluorosulfonyl)(trifluoromethanesulfonyl)imide lithium.

[0073] <"4"> "4" is at least one compound selected from the group consisting of compounds represented by the following general formula (4-1) and compounds represented by the following general formula (4-2).

[0074]

[0075] In the general formula (4-1), W represents a boron atom, a phosphorus atom, or a silicon atom, n1 represents an integer of 0 to 3, n2 represents an integer of 0 to 4, and p represents an integer of 0 or 1. ４１ represents an alkylene group having 1 to 10 carbon atoms, a halogenated alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a halogenated arylene group having 6 to 20 carbon atoms (these groups may contain a substituent or a heteroatom in the structure. When n1 is 2 or more, n1 R ４１ may be bonded to each other), and R ４２ represents a halogen atom, Y １ , Y ２ each independently represents an oxygen atom or a sulfur atom; Y ３ represents a carbon atom or a sulfur atom. ３ is 1 when it is a carbon atom, and 1 or 2 when it is a sulfur atom. ａ＋ represents an alkali metal cation, an alkaline earth metal cation, or an onium cation, a represents the valence of the corresponding cation, and a to d are 1 or 2, and a×b=c×d is satisfied.

[0076]

[0077] In general formula (4-2), R ４３ represents an alkylene group having 1 to 10 carbon atoms, a halogenated alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a halogenated arylene group having 6 to 20 carbon atoms (these groups may contain a substituent or a heteroatom in the structure), and r is 0 or 1. Y ４ represents a carbon atom or a sulfur atom. ４ is 1 when it is a carbon atom, and 1 or 2 when it is a sulfur atom. ２ represents a boron atom or a phosphorus atom, R ４４ represents a halogen atom. n3 represents W ２ is 2 for boron atoms and 4 for phosphorus atoms.

[0078] W represents a boron atom, a phosphorus atom, or a silicon atom, and is preferably a boron atom or a phosphorus atom.

[0079] R ４１ Examples of the alkylene group having 1 to 10 carbon atoms represented by R include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, an n-butylene group, and an n-hexylene group. ４１ Examples of the halogenated alkylene group having 1 to 10 carbon atoms represented by the formula (R) include groups in which any hydrogen atom in the alkylene group has been substituted with a halogen atom. ４１ Examples of the arylene group having 6 to 20 carbon atoms represented by R include a phenylene group and a naphthylene group. ４１ Examples of the halogenated arylene group having 6 to 20 carbon atoms represented by the formula (I) include groups in which any hydrogen atom of the above arylene group has been substituted with a halogen atom.

[0080] R ４１ is preferably a methylene group, an ethylene group, an n-propylene group, a difluoromethylene group, a tetrafluoroethylene group, or a hexafluoropropylene group, and more preferably a methylene group.

[0081] R ４２ Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, and an iodine atom, with a fluorine atom being preferred.

[0082] Y １ , Y ２ each independently represents an oxygen atom or a sulfur atom, and preferably all are oxygen atoms.

[0083] Y ３ represents a carbon atom or a sulfur atom, and is preferably a carbon atom.

[0084] M ａ＋ Examples of the alkali metal cation, alkaline earth metal cation, and onium cation represented by the formula (2-1) include M １ ｍ＋ Examples of the cations include the alkali metal cations, alkaline earth metal cations, and onium cations listed above, and preferred examples are also the same.

[0085] Examples of the compound represented by general formula (4-1) include tetrafluoroborate, bis(oxalato)borate, difluoro(oxalato)borate, tris(oxalato)phosphate, difluorobis(oxalato)phosphate, tetrafluoro(oxalato)phosphate, tris(oxalato)silicate, difluorobis(oxalato)silicate, difluoro(malonato)borate, tetrafluoro(malonato)phosphate, difluoro(sulfoacetato)borate, difluoro(maleato)borate, and difluoro(fumarato)borate.

[0086] R ４３ Examples of the alkylene group having 1 to 10 carbon atoms represented by the formula (R) include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, an n-butylene group, and an n-hexylene group. ４３ Examples of the halogenated alkylene group having 1 to 10 carbon atoms represented by the formula (R) include groups in which any hydrogen atom in the alkylene group has been substituted with a halogen atom. ４３ Examples of the arylene group having 6 to 20 carbon atoms represented by the formula (R) include a phenylene group and a naphthylene group. ４３ Examples of the halogenated arylene group having 6 to 20 carbon atoms represented by the formula (I) include groups in which any hydrogen atom of the above arylene group has been substituted with a halogen atom.

[0087] R ４３ As the alkyl group, a methylene group, an ethylene group, an n-propylene group, a difluoromethylene group, a tetrafluoroethylene group, or a hexafluoropropylene group is preferred, and a methylene group is more preferred.

[0088] R ４４ Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, and an iodine atom, with a fluorine atom being preferred.

[0089] Y ４ represents a carbon atom or a sulfur atom, and is preferably a carbon atom.

[0090] Examples of the compound represented by formula (4-2) include the following compounds:

[0091]

[0092] Among these, the following compounds are preferred:

[0093]

[0094] "4" is preferably at least one compound selected from the group consisting of tetrafluoroborate, bis(oxalato)borate, difluoro(oxalato)borate, tris(oxalato)phosphate, difluorobis(oxalato)phosphate, tetrafluoro(oxalato)phosphate, difluoro(malonato)borate, tetrafluoro(malonato)phosphate, tetrafluoro(picolinato)phosphate, and difluoro(picolinato)borate, and more preferably at least one compound selected from the group consisting of lithium tetrafluoroborate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium tris(oxalato)phosphate, lithium difluorobis(oxalato)phosphate, lithium tetrafluoro(oxalato)phosphate, lithium difluoro(malonato)borate, lithium tetrafluoro(malonato)phosphate, tetrafluoro(picolinato)phosphate, and difluoro(picolinato)borate.

[0095] <"5"> "5" is at least one compound represented by the following general formula (5).

[0096]

[0097] In general formula (5), R ５１ R each independently represents a group having a carbon-carbon unsaturated bond. ５２ When a plurality of are present, each independently represents a fluorine atom or a linear or branched alkyl group having 1 to 10 carbon atoms, and the alkyl group may have at least one of a fluorine atom and an oxygen atom. v represents an integer of 2 to 4.

[0098] R ５１Examples of groups having a carbon-carbon unsaturated bond represented by the formula (I) include alkenyl groups having 2 to 8 carbon atoms, such as vinyl groups, allyl groups, 1-propenyl groups, isopropenyl groups, 2-butenyl groups, and 1,3-butadienyl groups, or alkenyloxy groups derived from these groups; alkynyl groups having 2 to 8 carbon atoms, such as ethynyl groups, 2-propynyl groups, and 1,1-dimethyl-2-propynyl groups, or alkynyloxy groups derived from these groups; and aryl groups having 6 to 12 carbon atoms, such as phenyl groups, tolyl groups, and xylyl groups, or aryloxy groups derived from these groups. Furthermore, the above groups may contain fluorine atoms and oxygen atoms. Among these, groups containing a carbon-carbon unsaturated bond having 6 or less carbon atoms are preferred. When the carbon number is 6 or less, the resistance when a film is formed on an electrode tends to be relatively low. Specifically, groups selected from the group consisting of vinyl groups, allyl groups, 1-propenyl groups, ethynyl groups, and 2-propynyl groups are preferred.

[0099] R ５２ When there are a plurality of R's, each independently represents a fluorine atom or a linear or branched alkyl group having 1 to 10 carbon atoms. ５２ Examples of the linear or branched alkyl group having 1 to 10 carbon atoms represented by the formula (I) include a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, etc. Furthermore, the above groups may have at least one of a fluorine atom and an oxygen atom.

[0100] Among these, groups selected from a fluorine atom, a methyl group, an ethyl group, a propyl group, a 2,2,2-trifluoroethyl group, a 2,2,3,3-tetrafluoropropyl group, a 1,1,1-trifluoroisopropyl group, and a 1,1,1,3,3,3-hexafluoroisopropyl group tend to have a smaller initial resistance when a film is formed on an electrode, and as a result are preferred from the viewpoint of output characteristics.

[0101] In formula (5), v represents an integer of 2 to 4, preferably 3 or 4, and particularly preferably 4.

[0102] Specific examples of the compound represented by formula (5) are shown below, but the invention is not limited to these.

[0103]

[0104]

[0105] "5" is preferably at least one compound selected from the group consisting of trivinylmethylsilane, trivinylfluorosilane, and tetravinylsilane.

[0106] <"6"> "6" is at least one compound represented by the following general formula (6).

[0107]

[0108] In general formula (6), R ６１ and R ６２ R each independently represents a hydrogen atom, an alkyl group having 1 to 2 carbon atoms, a linear or branched alkenyl group having 2 to 5 carbon atoms, or an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms. ６１ and R ６２ Any hydrogen atom in the alkyl group, alkenyl group, or aryl group represented by the formula (I) may be substituted with a halogen atom. n6 is 0 or 1.

[0109] R ６１ and R ６２ When R is an alkyl group having 1 to 2 carbon atoms, examples of the alkyl group include a methyl group and an ethyl group. ６１ and R ６２ However, when R is a linear or branched alkenyl group having 2 to 5 carbon atoms, examples of the alkenyl group include a vinyl group, an allyl group, a 1-propenyl group, an isopropenyl group, a 2-butenyl group, and a 1,3-butadienyl group. ６１ and R ６２ However, when the aryl group is an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms, examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, etc. The number of carbon atoms of 6 to 10 refers to the total number of carbon atoms in the aryl group and, when the aryl group is substituted with an alkyl group, the total number of carbon atoms in the alkyl group.

[0110] At least one of the hydrogen atoms in the alkyl group, alkenyl group, and aryl group may be substituted with a halogen atom, such as a fluorine atom, a bromine atom, or an iodine atom, with a fluorine atom being preferred.

[0111] R ６１ and R ６２ preferably represents a hydrogen atom. When n6 is 0, R ６１ and the carbon atom to which R is bonded ６２ is bonded to the carbon atom to which it is bonded via a single bond. That is, "6" is preferably at least one compound selected from the group consisting of 1,3,2-dioxathiolane-2,2-dioxide and 1,3,2-dioxathiane-2,2-dioxide.

[0112] Specific examples of the compound represented by formula (6) are shown below, but the invention is not limited to these.

[0113]

[0114]

[0115] <"7"> The "7" is at least one compound selected from the group consisting of compounds represented by the following general formulas (7-1) and (7-2).

[0116]

[0117] In general formula (7-1), R ７０ ~R ７３ each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, or a fluoroalkyl group having 1 to 4 carbon atoms. n71 represents an integer of 1 to 3. In general formula (7-2), R ７４ ~R ７９ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a fluoroalkyl group having 1 to 4 carbon atoms. n72 represents an integer of 0 to 2.

[0118] In general formula (7-1), R ７０ ~R ７３Examples of the alkyl group represented by the formula (I) include alkyl groups having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, and an n-pentyl group.

[0119] R ７０ ~R ７３ Examples of the fluoroalkyl group represented by the formula (I) include fluoroalkyl groups having 1 to 4 carbon atoms, such as a trifluoromethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a 2,2,3,3-tetrafluoropropyl group, and a 1,1,1,3,3,3-hexafluoroisopropyl group.

[0120] R ７０ ~R ７３ is preferably a hydrogen atom, a fluorine atom or a trifluoromethyl group, more preferably a hydrogen atom.

[0121] In the general formula (7-1), n71 represents an integer of 1 to 3, may be 1 or 2, and is preferably 1.

[0122] Examples of the compound represented by general formula (7-1) include 1,3-propene sultone (1-propene-1,3-sultone), 1,4-butene sultone, 2,4-pentene sultone, 3,5-pentene sultone, 1-fluoro-1,3-propene sultone, 1-trifluoromethyl-1,3-propene sultone, 1,1,1-trifluoro-2,4-butene sultone, 1,4-butene sultone, and 1,5-pentene sultone.

[0123] In general formula (7-2), R ７４ ~R ７９ Examples of the alkyl group represented by the formula (I) include alkyl groups having 1 to 6 carbon atoms, such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, and an n-hexyl group.

[0124] R ７４ ~R ７９Examples of the fluoroalkyl group represented by the formula (I) include fluoroalkyl groups having 1 to 4 carbon atoms, such as a trifluoromethyl group, a 2,2-difluoroethyl group, a 2,2,2-trifluoroethyl group, a 2,2,3,3-tetrafluoropropyl group, and a 1,1,1,3,3,3-hexafluoroisopropyl group.

[0125] R ７４ ~R ７９ is preferably a hydrogen atom, a fluorine atom or a trifluoromethyl group, more preferably a hydrogen atom.

[0126] In the general formula (7-2), n72 represents an integer of 0 to 2, and may be 0 or 1, and is preferably 0. When n72 is 0, R ７６ and R ７７ and the carbon atom to which R is bonded ７８ and R ７９ is bonded to the carbon atom to which it is bonded by a single bond.

[0127] Examples of the compound represented by general formula (7-2) include 1,3-propane sultone, α-trifluoromethyl-γ-sultone, β-trifluoromethyl-γ-sultone, γ-trifluoromethyl-γ-sultone, α-methyl-γ-sultone, α,β-di(trifluoromethyl)-γ-sultone, α,α-di(trifluoromethyl)-γ-sultone, α-heptafluoropropyl-γ-sultone, 1,4-butane sultone, and 1,5-pentane sultone.

[0128] "7" is preferably at least one compound selected from the group consisting of 1,3-propane sultone and 1-propene-1,3-sultone.

[0129] In the nonaqueous electrolyte solution of the present disclosure, the content of the component (II) (hereinafter also referred to as the "concentration of (II)") relative to the total amount (100% by mass) of the nonaqueous electrolyte solution may have a lower limit of 0.01% by mass or more, 0.05% by mass or more, or 0.1% by mass or more. The upper limit of the concentration of (II) may be 10% by mass or less, 5% by mass or less, 4% by mass or less, or 2.5% by mass or less. By setting the concentration of (II) to 0.01% by mass or more, the effect of suppressing an increase in the initial resistance of a nonaqueous electrolyte battery using the nonaqueous electrolyte solution and the effect of improving the cycle characteristics can be easily obtained. On the other hand, by setting the concentration of (II) to 10% by mass or less, the increase in viscosity of the nonaqueous electrolyte solution can be suppressed, and the effect of suppressing an increase in the initial resistance of a nonaqueous electrolyte battery using the nonaqueous electrolyte solution can be easily obtained. The content of the component (II) relative to the total amount of the non-aqueous electrolyte may be 0.01% by mass to 10% by mass, or may be 0.01% by mass to 5% by mass. ３ SO ２ ) ２ , LiN(FSO ２ ) ２ , LiN (POF ２ ) ２ , LiCF ３ SO ３ , LiC ４ F ９ SO ３ , NaN(CF ３ SO ２ ) ２ , NaN(FSO ２ ) ２ , NaN(POF ２ ) ２ , NaCF ３ SO ３ , NaC ４ F ９ SO ３ The content of the non-aqueous electrolyte may be 0.01% by mass or more and 20% by mass or less relative to the total amount of the non-aqueous electrolyte.

[0130] In the nonaqueous electrolyte solution of the present disclosure, as component (II), one type of compound may be used alone, or two or more types of compounds may be mixed in any combination and ratio depending on the application.

[0131] The compounds represented by "2" to "7" above can be produced by known methods.

[0132] <(III) Solute> The nonaqueous electrolyte solution of the present disclosure contains a solute. The solute is not particularly limited, but is preferably an ionic salt, and more preferably an ionic salt containing fluorine.

[0133] The solute is preferably an ionic salt consisting of a pair of at least one cation selected from the group consisting of alkali metal ions such as lithium ions and sodium ions, alkaline earth metal ions, and quaternary ammonium ions, and at least one anion selected from the group consisting of hexafluorophosphate anion, perchlorate anion, hexafluoroarsenate anion, hexafluoroantimonate anion, and tris(trifluoromethanesulfonyl)methide anion.

[0134] The solute is LiPF ６ , LiSbF ６ , LiAsF ６ , LiClO ４ , LiAlO ２ , LiAlCl ４ , LiCl, and LiI, or NaPF ６ , NaSbF ６ , NaAsF ６ , NaClO ４ , NaAlO ２ , NaAlCl ４ , NaCl, and NaI.

[0135] These solutes may be used singly or in any combination and ratio depending on the application. Among them, in consideration of the energy density, output characteristics, life, etc. of the nonaqueous electrolyte battery, it is preferable that the cation is at least one selected from the group consisting of lithium, sodium, potassium, magnesium, and quaternary ammonium, and the anion is at least one selected from the group consisting of hexafluorophosphate anion and tetrafluoroborate anion.

[0136] The total amount of solutes in the nonaqueous electrolyte solution of the present disclosure (hereinafter also referred to as "solute concentration") is not particularly limited, but the lower limit is preferably 0.5 mol / L or more, more preferably 0.7 mol / L or more, and even more preferably 0.9 mol / L or more. The upper limit of the solute concentration is preferably 5 mol / L or less, more preferably 4 mol / L or less, and even more preferably 2 mol / L or less. By setting the solute concentration to 0.5 mol / L or more, it is possible to suppress a decrease in the cycle characteristics and output characteristics of the nonaqueous electrolyte battery due to a decrease in ionic conductivity, and by setting the solute concentration to 5 mol / L or less, it is possible to suppress a decrease in ionic conductivity and a decrease in the cycle characteristics and output characteristics of the nonaqueous electrolyte battery due to an increase in viscosity of the nonaqueous electrolyte.

[0137] <Regarding (IV) Non-aqueous Organic Solvent> The non-aqueous organic solvent (IV) (also referred to as "(IV)") contained in the non-aqueous electrolyte solution of the present disclosure will be described. The type of non-aqueous organic solvent (IV) is not particularly limited, and any non-aqueous organic solvent can be used. Specific examples of the non-aqueous organic solvent (IV) include the following non-aqueous organic solvents. Examples of cyclic esters include cyclic carbonates such as propylene carbonate (hereinafter sometimes referred to as "PC"), ethylene carbonate (hereinafter sometimes referred to as "EC"), fluoroethylene carbonate (hereinafter sometimes referred to as "FEC"), and butylene carbonate, as well as γ-butyrolactone and γ-valerolactone. Note that when the content of the FEC relative to the total amount of the non-aqueous electrolyte solution is 10% by mass or less, it is defined as an "other additive" as described below. Examples of chain esters include chain carbonates such as diethyl carbonate (hereinafter sometimes referred to as "DEC"), dimethyl carbonate (hereinafter sometimes referred to as "DMC"), ethyl methyl carbonate (hereinafter sometimes referred to as "EMC"), and methyl propyl carbonate, as well as methyl acetate, methyl propionate, and ethyl propionate (hereinafter sometimes referred to as "EP"). Examples of cyclic ethers include tetrahydrofuran, 2-methyltetrahydrofuran, and dioxane. Examples of chain ethers include dimethoxyethane and diethyl ether. Other examples include sulfone compounds and sulfoxide compounds such as dimethyl sulfoxide and sulfolane. Ionic liquids and the like can also be used.

[0138] (IV) The nonaqueous organic solvent may contain at least one selected from the group consisting of cyclic esters, chain esters, cyclic ethers, chain ethers, sulfone compounds, sulfoxide compounds, and ionic liquids.

[0139] The cyclic ester is a cyclic carbonate, and the cyclic carbonate may be at least one selected from the group consisting of ethylene carbonate, propylene carbonate, and fluoroethylene carbonate.

[0140] The chain ester is a chain carbonate, and the chain carbonate may be at least one selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, and methyl propyl carbonate.

[0141] In the nonaqueous electrolyte solution of the present disclosure, one type of compound may be used alone as (IV), or two or more types of compounds may be mixed in any combination and ratio depending on the application.

[0142] The content of the cyclic carbonate is not particularly limited and may be any content as long as it does not significantly impair the effects of the present disclosure. However, when one type is used alone, the content is 3 vol% or more, more preferably 5 vol% or more, based on 100 vol% of the nonaqueous organic solvent. By setting the content within this range, a decrease in electrical conductivity due to a decrease in the dielectric constant of the nonaqueous electrolyte can be avoided, and the large-current discharge characteristics, stability with respect to the negative electrode, and cycle characteristics of the nonaqueous electrolyte battery can be easily maintained within good ranges. Furthermore, the content is usually 90 vol% or less, preferably 85 vol% or less, and more preferably 80 vol% or less. Setting the content within this range allows the viscosity of the nonaqueous electrolyte to be within an appropriate range, suppresses a decrease in ionic conductivity, and ultimately facilitates maintaining good load characteristics of the nonaqueous electrolyte battery.

[0143] Additionally, any combination of two or more cyclic carbonates can be used. One preferred combination is a combination of ethylene carbonate and propylene carbonate. In this case, the volume ratio of ethylene carbonate to propylene carbonate is preferably 99:1 to 40:60, and particularly preferably 95:5 to 50:50. Furthermore, the amount of propylene carbonate relative to the total nonaqueous organic solvent is not particularly limited and may be any amount as long as it does not significantly impair the effects of the present disclosure. However, it is usually 1% by volume or more, preferably 2% by volume or more, more preferably 3% by volume or more, and usually 30% by volume or less, preferably 25% by volume or less, and more preferably 20% by volume or less. A propylene carbonate content within this range is preferred because it maintains the properties of the combination of ethylene carbonate and dialkyl carbonates while providing even more excellent low-temperature properties.

[0144] The chain ester may be used alone or in any combination and ratio of two or more. The content of the chain ester is not particularly limited, but is typically 15% by volume or more, preferably 20% by volume or more, and more preferably 25% by volume or more, based on 100% by volume of the nonaqueous organic solvent. Furthermore, it is typically 90% by volume or less, preferably 85% by volume or less, and more preferably 80% by volume or less. By setting the content of the chain ester within the above range, the viscosity of the nonaqueous electrolyte can be adjusted to an appropriate range, a decrease in ionic conductivity can be suppressed, and the input / output characteristics and charge / discharge rate characteristics of the nonaqueous electrolyte battery can be easily adjusted to a good range. Furthermore, a decrease in electrical conductivity due to a decrease in the dielectric constant of the nonaqueous electrolyte can be avoided, and the input / output characteristics and charge / discharge rate characteristics of the nonaqueous electrolyte battery can be easily adjusted to a good range. Furthermore, by combining a specific chain ester with ethylene carbonate at a specific content, battery performance can be significantly improved.

[0145] For example, when dimethyl carbonate and ethyl methyl carbonate are selected as the specific chain esters, the content of ethylene carbonate is not particularly limited and can be any amount as long as it does not significantly impair the effects of the present disclosure, but is usually 5% by volume or more, preferably 10% by volume or more, and usually 45% by volume or less, preferably 40% by volume or less, the content of dimethyl carbonate is usually 20% by volume or more, preferably 30% by volume or more, and usually 50% by volume or less, preferably 45% by volume or less, and the content of ethyl methyl carbonate is usually 20% by volume or more, preferably 30% by volume or more, and usually 50% by volume or less, preferably 45% by volume or less. By setting the content within the above ranges, the low-temperature deposition temperature of the electrolyte is lowered, while the viscosity of the nonaqueous electrolyte is also lowered, improving ionic conductivity and allowing high input / output even at low temperatures.

[0146] The content of the chain ether is not particularly limited and may be any content as long as it does not significantly impair the effects of the present disclosure, but is typically 1 vol% or more, preferably 2 vol% or more, more preferably 3 vol% or more, and typically 30 vol% or less, preferably 25 vol% or less, more preferably 20 vol% or less, based on 100 vol% of the nonaqueous organic solvent. When the content of the chain ether is within the above range, it is easy to ensure the effect of improving the degree of lithium ion dissociation of the chain ether and improving ionic conductivity due to reduced viscosity. Furthermore, when the negative electrode active material is a carbonaceous material, the phenomenon of co-insertion of the chain ether with lithium ions can be suppressed, thereby allowing the input / output characteristics and charge / discharge rate characteristics to be within appropriate ranges.

[0147] The content of the sulfone compound is not particularly limited and may be any content as long as it does not significantly impair the effects of the present disclosure, but is usually 0.3 vol% or more, preferably 0.5 vol% or more, more preferably 1 vol% or more, and usually 40 vol% or less, preferably 35 vol% or less, more preferably 30 vol% or less, based on 100 vol% of the nonaqueous organic solvent. If the content of the sulfone compound is within the above range, it is easy to obtain an effect of improving durability such as cycle characteristics and storage characteristics, and it is also possible to keep the viscosity of the nonaqueous electrolyte within an appropriate range, avoid a decrease in electrical conductivity, and keep the input / output characteristics and charge / discharge rate characteristics of the nonaqueous electrolyte battery within appropriate ranges.

[0148] <Regarding Other Additives> As long as the gist of the present disclosure is not impaired, additive components generally used in the nonaqueous electrolyte solution of the present disclosure may be further added in any ratio. Specific examples of other additives include cyclohexylbenzene, cyclohexylfluorobenzene, fluorobenzene, biphenyl, difluoroanisole, tert-butylbenzene, tert-amylbenzene, 2-fluorotoluene, 2-fluorobiphenyl, vinylene carbonate, vinylene carbonate oligomer (having a number average molecular weight of 170 to 5000 in terms of polystyrene), dimethylvinylene carbonate, vinylethylene carbonate, fluoroethylene carbonate, trans-difluoroethylene carbonate, methylpropargyl carbonate, ethylpropargyl carbonate, dipropargyl carbonate, ethynylethylene carbonate, maleic anhydride, succinic anhydride, and 1,2-ethane. Examples of suitable additives include disulfonic acid anhydride, methylenemethane disulfonate, dimethylenemethane disulfonate, trimethylenemethane disulfonate, methyl methanesulfonate, 1,6-diisocyanatohexane, tris(trimethylsilyl)borate, succinonitrile, (ethoxy)pentafluorocyclotriphosphazene, lithium monofluorophosphate, sodium monofluorophosphate, potassium monofluorophosphate, methanesulfonyl fluoride, ethenesulfonyl fluoride, phenyl difluorophosphate, 1,3-dimethyl-1,3-divinyl-1,3-di(1,1,1,3,3,3-hexafluoroisopropyl)disiloxane, and nitrates. The nonaqueous electrolyte solution of the present disclosure may contain at least one of the additives. The content of the additive in the nonaqueous electrolyte solution may be 0.01% by mass or more and 5% by mass or less, based on the total amount of the nonaqueous electrolyte solution. By adding the above-described additives to the nonaqueous electrolyte solution of the present disclosure, at least one of the effects of preventing overcharge, forming a negative electrode film, and protecting the positive electrode may be enhanced.

[0149] The nonaqueous electrolyte solution of the present disclosure may contain, as other additives, a compound represented by the following general formula (3-4), excluding compounds corresponding to the above general formula (3-2).

[0150]

[0151] In general formula (3-4), R ３１ ~R ３３ represents X in the general formula (3-2). ２ However, R ３１ ~R ３３ At least one of M is a fluorine atom. ２ ｍ＋ represents an alkali metal cation, an alkaline earth metal cation, or an onium cation, and m represents an integer equal to the valence of the corresponding cation. ２ ｍ＋ The alkali metal cation, alkaline earth metal cation, and onium cation represented by M in the above general formula (3-2) are １ ｍ＋ Examples of cations include the alkali metal cations, alkaline earth metal cations, and onium cations listed above.

[0152] The content of the other additives in the non-aqueous electrolyte may be 0.01 mass % or more and 8 mass % or less with respect to the total amount of the non-aqueous electrolyte.

[0153] Furthermore, when the content of the ionic salts listed as solutes in the nonaqueous electrolyte solution is less than 0.5 mol / L, which is the lower limit of the preferred concentration of the solute, they can exert a negative electrode film-forming effect and a positive electrode-protecting effect as "other additives." In this case, the content of the ionic salts in the nonaqueous electrolyte solution may be 0.01% by mass to 5% by mass.

[0154] In addition, alkali metal salts other than the above solutes may be used as additives. Specific examples include carboxylates such as lithium acrylate, sodium acrylate, lithium methacrylate, and sodium methacrylate, and sulfates such as lithium methyl sulfate, sodium methyl sulfate, lithium ethyl sulfate, and sodium ethyl sulfate.

[0155] From the viewpoint of improving the durability (life) of the battery, the nonaqueous electrolyte solution of the present disclosure may contain, among the above-mentioned other additives, at least one selected from vinylene carbonate and fluoroethylene carbonate in an amount of 0.01 to 5 mass % relative to the total amount of the nonaqueous electrolyte when the nonaqueous electrolyte battery is a lithium ion battery, or at least one selected from vinylene carbonate and fluoroethylene carbonate in an amount of 0.01 to 5 mass % relative to the total amount of the nonaqueous electrolyte when the nonaqueous electrolyte battery is a sodium ion battery.

[0156] The nonaqueous electrolyte solution of the present disclosure may also contain a polymer, and may be used after being quasi-solidified with a gelling agent or crosslinked polymer, as in the case of a nonaqueous electrolyte battery known as a polymer battery. Polymer solid electrolytes also include those containing a nonaqueous organic solvent as a plasticizer.

[0157] The polymer is not particularly limited as long as it is an aprotic polymer that can dissolve the sulfonic acid anhydride "1" represented by the general formula (1) above, at least one compound selected from the group represented by "2" to "7" above, the solute, and the other additives. Examples include polymers having polyethylene oxide in the main chain or side chain, homopolymers or copolymers of polyvinylidene fluoride, methacrylic acid ester polymers, and polyacrylonitrile. When a plasticizer is added to these polymers, aprotic nonaqueous organic solvents are preferred among the nonaqueous organic solvents listed above.

[0158] 2. Nonaqueous Electrolyte Battery The nonaqueous electrolyte battery of the present disclosure includes at least the nonaqueous electrolyte of the present disclosure, a negative electrode, and a positive electrode. Preferably, the battery also includes a separator, an outer casing, etc. The present invention also relates to a nonaqueous electrolyte battery including at least a positive electrode, a negative electrode, a separator, and the nonaqueous electrolyte of the present disclosure.

[0159] The negative electrode is not particularly limited, but may be made of a material that allows reversible insertion and desorption of alkali metal ions such as lithium ions and sodium ions, or alkaline earth metal ions.

[0160] For example, in the case of a lithium-ion secondary battery in which the cation is mainly lithium, the negative electrode active material constituting the negative electrode is capable of doping and dedoping lithium ions. For example, carbon materials having a d value of the lattice plane (002 plane) of 0.340 nm or less in X-ray diffraction, carbon materials having a d value of the lattice plane (002 plane) of more than 0.340 nm in X-ray diffraction, oxides of one or more metals selected from Si, Sn, and Al, alloys containing one or more metals selected from Si, Sn, and Al, or alloys of these metals or alloys with lithium, and lithium titanium oxides. These negative electrode active materials can be used alone or in combination of two or more. Lithium metal, metal nitrides, tin compounds, conductive polymers, etc. may also be used.

[0161] For example, in the case of a sodium-ion secondary battery in which the cation is primarily sodium, the negative electrode active material constituting the negative electrode may be sodium metal, an alloy of sodium metal with other metals such as tin, an intermetallic compound of sodium metal with other metals, various carbon materials such as hard carbon, metal oxides such as titanium oxide, metal nitrides, tin (simple substance), tin compounds, activated carbon, conductive polymers, etc. In addition to these, phosphorus (simple substance) such as red phosphorus and black phosphorus, phosphorus compounds such as Co—P, Cu—P, Sn—P, Ge—P, and Mo—P, antimony (simple substance), antimony compounds such as Sb / C and Bi—Sb, etc., may also be used. These negative electrode active materials may be used alone or in combination of two or more types.

[0162] The positive electrode is not particularly limited, but may be made of a material that allows reversible insertion and desorption of alkali metal ions such as lithium ions and sodium ions, or alkaline earth metal ions.

[0163] For example, when the cation is lithium, the positive electrode material is LiCoO ２ , LiNiO ２ , LiMnO ２ , LiMn ２ O ４Lithium-containing transition metal composite oxides such as those described above, in which a plurality of transition metals such as Co, Mn, and Ni are mixed, those in which a part of the transition metal in the lithium-containing transition metal composite oxide is replaced with a metal other than the transition metal, and LiFePO , which is called olivine. ４ , LiCoPO ４ , LiMnPO ４ transition metal phosphate compounds such as TiO ２ , V ２ O ５ , MoO ３ oxides such as TiS ２ , sulfides such as FeS, conductive polymers such as polyacetylene, polyparaphenylene, polyaniline, and polypyrrole, activated carbon, radical-generating polymers, carbon materials, etc. may also be used. １／３ Mn １／３ Co １／３ ]O ２ , Li[Ni ０．４５ Mn ０．３５ Co ０．２ ]O ２ , Li[Ni ０．５ Mn ０．３ Co ０．２ ]O ２ , Li[Ni ０．６ Mn ０．２ Co ０．２ ]O ２ , Li[Ni ０．８ Mn ０．１ Co ０．１ ]O ２ (hereinafter, sometimes referred to as "NCM811"), Li[Ni ０．４９ Mn ０．３ Co ０．２ Zr ０．０１ ]O ２ , Li[Ni ０．４９ Mn ０．３ Co ０．２ Mg ０．０１ ]O ２ , LiNi ０．８ Co ０．２ O ２ , LiNi ０．８５ Co ０．１０ Al ０．０５ O ２ , LiNi ０．８７Co ０．１０ Al ０．０３ O ２ , LiNi ０．９０ Co ０．０７ Al ０．０３ O ２ , LiNi ０．６ Co ０．３ Al ０．１ O ２、 LiMn １．５ Ni ０．５ O ４ etc.

[0164] For example, when the cation is sodium, the positive electrode material (positive electrode active material) is NaCrO ２ , NaFe ０．５ Co ０．５ O ２ , NaFe ０．４ Mn ０．３ Ni ０．３ O ２ , NaNi ０．５ Ti ０．３ Mn ０．２ O ２ , NaNi １／３ Ti １／３ Mn １／３ O ２ , NaNi ０．３３ Ti ０．３３ Mn ０．１６ Mg ０．１７ O ２ , Na ２／３ Ni １／３ Ti １／６ Mn １／２ O ２ , Na ２／３ Ni １／３ Mn ２／３ O ２ sodium-containing transition metal composite oxides such as those described above, in which a plurality of transition metals such as Co, Mn, and Ni are mixed, sodium-containing transition metal composite oxides in which a part of the transition metal is replaced with a metal other than the transition metal, NaFePO ４ , NaVPO ４ F, Na ３ V ２ (P.O. ４ ) ３ , Na ２ Fe ２ (SO４ ) ３ Polyanion type compounds such as those of the formula Na ａ M ｂ [Fe(CN) ６ ] ｃ (M=Cr, Mn, Fe, Co, Ni, Cu, or Zn, and 0≦a≦2, 0.5≦b≦1.5, 0.5≦c≦1.5), TiO ２ , V ２ O ５ , MoO ３ oxides such as TiS ２ Alternatively, sulfides such as FeS, conductive polymers such as polyacetylene, polyparaphenylene, polyaniline, and polypyrrole, activated carbon, radical-generating polymers, carbon materials, and the like may be used.

[0165] The positive electrode and negative electrode materials may contain acetylene black, ketjen black, carbon fiber, or graphite as a conductive material, and polytetrafluoroethylene, polyvinylidene fluoride, SBR resin, or the like as a binder, and may further be molded into a sheet to form an electrode sheet.

[0166] As a separator for preventing contact between the positive electrode and the negative electrode, a nonwoven fabric or porous sheet made of polypropylene, polyethylene, paper, glass fiber, or the like may be used.

[0167] The above elements are assembled into an electrochemical device having a coin-like, cylindrical, rectangular, aluminum laminate sheet, or other shape.

[0168] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0169] The compounds of component (I) and component (II) used in each of the examples and comparative examples are shown below. Compound (1-1): Methanesulfonic anhydride Compound (1-2): Ethanesulfonic anhydride Compound (2-1): Lithium difluorophosphate Compound (2-2): Lithium fluorosulfonate Compound (3-1): Lithium bis(fluorosulfonyl)imide Compound (4-1): Lithium bis(oxalato)borate Compound (4-2): Lithium difluoro(oxalato)borate Compound (4-3): Lithium tris(oxalato)phosphate Compound (4-4): Lithium difluorobis(oxalato)phosphate Compound (4-5): Lithium tetrafluoro(oxalato)phosphate Compound (4-6): Lithium tetrafluoroborate Compound (5-1): Trivinylmethylsilane Compound (5-2): Trivinylfluorosilane Compound (5-3): Tetravinylsilane Compound (6-1): 1,3,2-dioxathiolane-2,2-dioxide Compound (7-1): 1,3-propanesultone Compound (7-2): 1-propene-1,3-sultone

[0170] The structures of the comparative compounds (3-X) and (5-X) are shown below.

[0171]

[0172] [Preparation of Non-Aqueous Electrolyte] [Example 1-1] In a glove box with a dew point of -60°C or less, EC, EMC, and DMC were mixed in a volume ratio of EC:EMC:DMC=25:55:20 (component (IV)). Then, while maintaining the internal temperature at 40°C or less, LiPF 5 was added in an amount to give a concentration of 1.0 mol / L. ６ Compound (1-1) (component (I)) was added to the non-aqueous electrolyte solution so that the concentration was 1.0 mass % relative to the total amount of the non-aqueous electrolyte solution, and compound (2-1) (component (II)) was further added to the non-aqueous electrolyte solution so that the concentration was 1.0 mass % relative to the total amount of the non-aqueous electrolyte solution, and the mixture was stirred for 1 hour to dissolve, thereby preparing the non-aqueous electrolyte solution according to Example 1-1.

[0173] In addition, the types and concentrations of component (I), component (II), and other additives were changed as shown in Tables 1 to 12 below, and otherwise non-aqueous electrolyte solutions according to Examples 1-2 to 1-87, Comparative Examples 1-1 to 1-43, Examples 2-1 to 2-87, and Comparative Examples 2-1 to 2-43 were prepared using the same procedure as in the preparation of electrolyte solution 1-1.

[0174] In the "other additives" columns in Tables 7 to 12, VC represents vinylene carbonate and FEC represents fluoroethylene carbonate. The concentrations of component (I), component (II), and other additives in Tables 1 to 12 all represent concentrations relative to the total amount of the nonaqueous electrolyte.

[0175] [Preparation of non-aqueous electrolyte battery] (Lithium ion battery: Preparation of NCM811 positive electrode) LiNi ０．８ Co ０．１ Mn ０．１ O ２ A positive electrode composite paste was prepared by mixing 92.0% by mass of the powder with 3.5% by mass of polyvinylidene fluoride (PVDF) as a binder and 4.5% by mass of acetylene black as a conductive material, and then adding N-methyl-2-pyrrolidone. This paste was applied to both sides of aluminum foil (A1085), dried, pressed, and then punched out to a 4 cm x 5 cm piece to obtain a test NCM811 positive electrode.

[0176] (Preparation of Natural Graphite Negative Electrode) 97.0% by mass of natural graphite powder, 2.0% by mass of styrene-butadiene rubber as a binder, 1.0% by mass of sodium carboxymethyl cellulose, and water were mixed to prepare a negative electrode composite paste. This paste was applied to one side of copper foil, dried, pressed, and then punched out to a size of 4.5 cm x 5.5 cm to obtain a test natural graphite negative electrode.

[0177] (Preparation of silicon-containing graphite negative electrode) 72.0 mass % of artificial graphite powder, SiO ｘA negative electrode composite paste was prepared by mixing 20.0% by mass of (x = 1), 3.0% by mass of a conductive material (HS-100 manufactured by Denka), 2.0% by mass of carbon nanofiber (VGCF manufactured by Showa Denko), 2.0% by mass of styrene butadiene rubber, 1.0% by mass of sodium carboxymethyl cellulose, and water. This paste was applied to one side of copper foil, dried, pressed, and then punched out to 4.5 cm x 5.5 cm to obtain a silicon-containing graphite negative electrode for testing.

[0178] (Preparation of Nonaqueous Electrolyte Battery) In an argon atmosphere with a dew point of −50° C. or less, a terminal was welded to the above-described NCM811 positive electrode, and then the positive electrode was sandwiched between two polyethylene separators (5 cm × 6 cm). The outer surface of the separator was then sandwiched between two natural graphite or silicon-containing graphite negative electrodes with pre-welded terminals, with the negative electrode active material facing the positive electrode active material. The resulting battery was then placed in an aluminum-laminated bag with an opening on one side. A nonaqueous electrolyte was vacuum-injected into the bag, and the opening was then heat-sealed to prepare aluminum-laminated nonaqueous electrolyte batteries of the Examples and Comparative Examples. The nonaqueous electrolytes listed in Tables 1 to 12 were used. The Examples and Comparative Examples in Tables 1 to 6 used a natural graphite negative electrode, while the Examples and Comparative Examples in Tables 7 to 12 used a silicon-containing graphite negative electrode. Using the cells prepared in the above manner, the initial resistance, cycle characteristics, and high-temperature storage characteristics were evaluated as described below.

[0179] [Evaluation of non-aqueous electrolyte batteries] (Evaluation of non-aqueous electrolyte batteries listed in Tables 1 to 6) - Initial charge / discharge - The fabricated non-aqueous electrolyte batteries were placed in a thermostatic chamber at 25°C and connected to a charge / discharge device in this state. Current density: 0.38 mA / cm ２ After maintaining 4.2 V for 1 hour, the battery was charged at a current density of 0.38 mA / cm ２ The battery was discharged at 100 V to 2.5 V. This was defined as one charge / discharge cycle, and a total of three charge / discharge cycles were performed to stabilize the battery. The discharge capacity at the third cycle was defined as the initial charge / discharge capacity.

[0180] <Initial resistance> 25℃, 0.38mA / cm after initial charge / discharge ２The battery was charged to 4.2 V at 100 V, and the resistance value was measured by impedance measurement. The initial resistance values ​​of Examples 1-1 to 1-87 and Comparative Examples 1-1 to 1-43 shown in Tables 1 to 6 are relative values ​​when the initial resistance value of Comparative Example 1-1 is set to 100.

[0181] <High-Temperature Storage Characteristics> After the initial charge and discharge, the nonaqueous electrolyte batteries of Examples 1-1 to 1-87 and Comparative Examples 1-1 to 1-43 shown in Tables 1 to 6 were charged at an upper limit voltage of 4.2 V and a current of 0.38 mA / cm ２ After that, the battery was taken out of the charge / discharge device maintained at 25°C, placed in a thermostatic chamber at 60°C, and stored for 14 days. Thereafter, the battery was placed in a charge / discharge device maintained at 25°C, and charged at 0.38 mA / cm until the discharge cut-off voltage reached 2.5 V. ２ The cells were discharged, and the degree of deterioration of the cells was evaluated based on the discharge capacity retention rate after storage. The discharge capacity retention rate after storage at 60°C was calculated using the following formula: (Discharge capacity retention rate after storage at 60°C) Discharge capacity retention rate (%) = (Discharge capacity after storage at 60°C / Initial charge / discharge capacity) × 100. The values ​​of the discharge capacity retention rates after storage at 60°C for Examples 1-1 to 1-87 and Comparative Examples 1-1 to 1-43 shown in Tables 1 to 6 are relative values ​​when the discharge capacity retention rate after storage at 60°C for Comparative Example 1-1 is set to 100. The discharge capacity retention rates after storage at 60°C for Examples 1-1 to 1-87 and Comparative Examples 1-1 to 1-43 are referred to as "Capacity after storage at 60°C" in Tables 1 to 6.

[0182] (Resistance value after storage at 60°C) Next, at 25°C, 0.38 mA / cm ２ The batteries were charged to 4.2 V at 25°C, and the resistance values ​​were measured by impedance measurement. The resistance values ​​after storage at 60°C of Examples 1-1 to 1-87 and Comparative Examples 1-1 to 1-43 shown in Tables 1 to 6 are relative values ​​when the resistance value after storage at 60°C of Comparative Example 1-1 is set to 100. The resistance values ​​after storage at 60°C of Examples 1-1 to 1-87 and Comparative Examples 1-1 to 1-43 are listed as "resistance after storage at 60°C" in Tables 1 to 6.

[0183] (Evaluation of non-aqueous electrolyte batteries listed in Tables 7 to 12) - Initial charge / discharge - The fabricated non-aqueous electrolyte batteries were placed in a thermostatic chamber at 25°C and connected to a charge / discharge device in this state. Current density: 0.38 mA / cm ２After maintaining 4.2 V for 1 hour, the battery was charged at a current density of 0.38 mA / cm ２ This was counted as one charge-discharge cycle, and a total of three charge-discharge cycles were carried out to stabilize the battery.

[0184] <Initial resistance> 25℃, 0.38mA / cm after initial charge / discharge ２ The batteries were charged to 4.2 V at 100 V, and the resistance values ​​were measured by impedance measurement. The initial resistance values ​​shown in Examples 2-1 to 2-87 and Comparative Examples 2-1 to 2-43 in Tables 7 to 12 are relative values ​​when the initial resistance value of Comparative Example 2-1 is set to 100.

[0185] <Cycle Characteristics Test> A charge-discharge test was carried out at an ambient temperature of 25°C using the nonaqueous electrolyte batteries of Examples 2-1 to 2-87 and Comparative Examples 2-1 to 2-43 shown in Tables 7 to 12, and cycle characteristics were evaluated. Charging was performed up to 4.2 V and discharging was performed up to 2.5 V, with a current density of 1.9 mA / cm. ２ Charge and discharge cycles were repeated at 100°C. The degree of cell deterioration was evaluated based on the discharge capacity retention rate after 200 cycles. The discharge capacity retention rate after 200 cycles was calculated using the following formula: (Discharge Capacity Retention Rate After 200 Cycles) Discharge Capacity Retention Rate (%) = (Discharge Capacity After 200 Cycles / Initial Discharge Capacity) × 100. The values ​​of the discharge capacity retention rates after 200 cycles in Examples 2-1 to 2-87 and Comparative Examples 2-1 to 2-43 listed in Tables 7 to 12 are relative values, with the discharge capacity retention rate after 200 cycles of Comparative Example 2-1 defined as 100. The discharge capacity at the first cycle in the cycle characteristic test at an ambient temperature of 25°C was defined as the initial discharge capacity. The discharge capacity retention rates after 200 cycles of Examples 2-1 to 2-87 and Comparative Examples 2-1 to 2-43 are listed as "Capacity After 200 Cycles" in Tables 7 to 12.

[0186] (Resistance value after 200 cycles) The nonaqueous electrolyte battery after the cycle characteristic test was subjected to a test at 25°C and 0.38 mA / cm ２The batteries were charged to 4.2 V at 100 V, and the resistance values ​​were measured by impedance measurement. The resistance values ​​after 200 cycles of Examples 2-1 to 2-87 and Comparative Examples 2-1 to 2-43 shown in Tables 7 to 12 are relative values ​​when the resistance value after 200 cycles of Comparative Example 2-1 is set to 100. The resistance values ​​after 200 cycles of Examples 2-1 to 2-87 and Comparative Examples 2-1 to 2-43 are listed as "resistance after 200 cycles" in Tables 7 to 12.

[0187]

[0188]

[0189]

[0190]

[0191]

[0192]

[0193]

[0194]

[0195]

[0196]

[0197]

[0198]

[0199] The present disclosure provides a nonaqueous electrolyte and a nonaqueous electrolyte battery that can reduce the initial resistance value of a battery.

[0200] Although the present disclosure has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present disclosure. This application is based on a Japanese patent application (Patent Application No. 2023-123779) filed on July 28, 2023, the contents of which are incorporated herein by reference.

Claims

1. A non-aqueous electrolyte solution comprising: (I) at least one sulfonic acid anhydride "1" represented by the following general formula (1); (II) at least one compound selected from the group represented by the following "2," "3," "4," "5," "6," and "7"; (III) a solute; and (IV) a non-aqueous organic solvent. In general formula (1), R １ and R ２ R each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkenyl group having 2 to 10 carbon atoms, or an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms. １ and R ２ Any hydrogen atom in the alkyl group, alkenyl group, and aryl group represented by the formula (2-1) may be substituted with a halogen atom. The formula (2-2) represents at least one compound selected from the group consisting of compounds represented by the following formulas (2-1) and (2-2): In general formula (2-1), R ３ and R ４ are each independently a fluorine atom, or an organic group selected from a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may contain a fluorine atom, an oxygen atom, or an unsaturated bond. Furthermore, general formula (2-1) contains at least one P-F bond. In general formula (2-2), X １ is a fluorine atom, or an organic group selected from a linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may contain at least one fluorine atom, and the organic group may also contain an oxygen atom or an unsaturated bond. １ ｍ＋ is a proton, a metal cation, or an onium cation. m represents the valence of the corresponding cation. The "3" is at least one compound selected from the group consisting of compounds represented by the following general formulas (3-1) to (3-3): In general formulas (3-1) to (3-3), R ５ ~R １０ are each independently a fluorine atom or an organic group selected from a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may contain a fluorine atom, an oxygen atom, or an unsaturated bond. ２ ~X ４ are each independently a fluorine atom, or an organic group selected from a linear or branched alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkynyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a cycloalkenyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, a linear or branched alkoxy group having 1 to 10 carbon atoms, an alkenyloxy group having 2 to 10 carbon atoms, an alkynyloxy group having 2 to 10 carbon atoms, a cycloalkoxy group having 3 to 10 carbon atoms, a cycloalkenyloxy group having 3 to 10 carbon atoms, and an aryloxy group having 6 to 10 carbon atoms, and the organic group may also contain a fluorine atom, an oxygen atom, or an unsaturated bond. In addition, at least one P-F bond and / or S-F bond is contained in the general formulas (3-1) to (3-3). M １ ｍ＋ is a proton, a metal cation, or an onium cation. m represents the valence of the corresponding cation. The "4" is at least one compound selected from the group consisting of compounds represented by the following general formula (4-1) and compounds represented by the following general formula (4-2): In the general formula (4-1), W represents a boron atom, a phosphorus atom, or a silicon atom, n1 represents an integer of 0 to 3, n2 represents an integer of 0 to 4, and p represents an integer of 0 or 1. ４１ represents an alkylene group having 1 to 10 carbon atoms, a halogenated alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a halogenated arylene group having 6 to 20 carbon atoms (these groups may contain a substituent or a heteroatom in the structure. When n1 is 2 or more, n1 R ４１ may be bonded to each other), R ４２ represents a halogen atom; Y １ , Y ２ each independently represents an oxygen atom or a sulfur atom; Y ３ represents a carbon atom or a sulfur atom. ３ is 1 when it is a carbon atom, and is 1 or 2 when it is a sulfur atom. ａ＋ represents an alkali metal cation, an alkaline earth metal cation, or an onium cation, a represents the valence of the corresponding cation, and a to d are 1 or 2, and a×b=c×d is satisfied. In general formula (4-2), R ４３ represents an alkylene group having 1 to 10 carbon atoms, a halogenated alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 20 carbon atoms, or a halogenated arylene group having 6 to 20 carbon atoms (these groups may contain a substituent or a heteroatom in the structure), and r is 0 or 1. Y ４ represents a carbon atom or a sulfur atom. ４ is 1 when it is a carbon atom, and 1 or 2 when it is a sulfur atom. ２ represents a boron atom or a phosphorus atom, R ４４ represents a halogen atom. n3 represents W ２ is 2 when it is a boron atom, and is 4 when it is a phosphorus atom. The "5" is at least one compound represented by the following general formula (5): In general formula (5), R ５１ Each independently represents a group having a carbon-carbon unsaturated bond. ５２ When there are a plurality of, each independently represents a fluorine atom or a linear or branched alkyl group having 1 to 10 carbon atoms, and the alkyl group may have at least one of a fluorine atom and an oxygen atom. v represents an integer of 2 to 4. The "6" represents at least one compound represented by the following general formula (6), In general formula (6), R ６１ and R ６２ R each independently represents a hydrogen atom, an alkyl group having 1 to 2 carbon atoms, a linear or branched alkenyl group having 2 to 5 carbon atoms, or an aryl group which may be substituted with an alkyl group having 6 to 10 carbon atoms. ６１ and R ６２ Any hydrogen atom in the alkyl group, alkenyl group, and aryl group represented by the formula (7-1) may be substituted with a halogen atom. n6 is 0 or 1. The formula "7" is at least one compound selected from the group consisting of compounds represented by the following formulas (7-1) to (7-2). In general formula (7-1), R ７０ ~R ７３ each independently represents a hydrogen atom, a fluorine atom, an alkyl group having 1 to 5 carbon atoms, or a fluoroalkyl group having 1 to 4 carbon atoms. n71 represents an integer of 1 to 3. In general formula (7-2), R ７４ ~R ７９ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a fluoroalkyl group having 1 to 4 carbon atoms. n72 represents an integer of 0 to 2.

2. The nonaqueous electrolyte according to claim 1, wherein the content of said (I) is 0.01% by mass to 10% by mass relative to the total amount of said nonaqueous electrolyte.

3. The non-aqueous electrolyte according to claim 1, wherein the content of said (II) is 0.01% by mass to 10% by mass relative to the total amount of said non-aqueous electrolyte.

4. The nonaqueous electrolyte according to claim 1 or 2, wherein the (I) is at least one selected from the group consisting of methanesulfonic anhydride and ethanesulfonic anhydride.

5. The nonaqueous electrolyte according to claim 1 or 2, wherein the "2" is at least one compound selected from the group consisting of lithium difluorophosphate, lithium fluorosulfonate, and lithium trifluoromethanesulfonate.

6. The nonaqueous electrolyte according to claim 1 or 2, wherein the "3" is at least one compound selected from the group consisting of bis(fluorosulfonyl)imide lithium, (fluorosulfonyl)(difluorophosphoryl)imide lithium, bis(trifluoromethanesulfonyl)imide lithium, bis(difluorophosphoryl)imide lithium, bis(pentafluoroethanesulfonyl)imide lithium, and (fluorosulfonyl)(trifluoromethanesulfonyl)imide lithium.

7. The nonaqueous electrolyte according to claim 1 or 2, wherein the "4" is at least one compound selected from the group consisting of lithium tetrafluoroborate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium tris(oxalato)phosphate, lithium difluorobis(oxalato)phosphate, lithium tetrafluoro(oxalato)phosphate, lithium difluoro(malonato)borate, lithium tetrafluoro(malonato)phosphate, tetrafluoro(picolinato)phosphate, and difluoro(picolinato)borate.

8. The non-aqueous electrolyte according to claim 1 or 2, wherein the "5" is at least one compound selected from the group consisting of trivinylmethylsilane, trivinylfluorosilane, and tetravinylsilane.

9. The nonaqueous electrolyte according to claim 1 or 2, wherein the "6" is at least one compound selected from the group consisting of 1,3,2-dioxathiolane-2,2-dioxide and 1,3,2-dioxathiane-2,2-dioxide.

10. The compound (III) is LiPF ６ , LiSbF ６ , LiAsF ６ , LiClO ４ , LiAlO ２ , LiAlCl ４ At least one selected from the group consisting of LiCl, LiI, and NaPF ６ , NaSbF ６ , NaAsF ６ , NaClO ４ , NaAlO ２ , NaAlCl ４ 3. The nonaqueous electrolyte according to claim 1, wherein the nonaqueous electrolyte is at least one selected from the group consisting of NaCl, NaI, and NaI.

11. The nonaqueous electrolyte according to claim 1 or 2, wherein the (IV) includes at least one selected from the group consisting of cyclic esters, chain esters, cyclic ethers, chain ethers, sulfone compounds, sulfoxide compounds, and ionic liquids.

12. The nonaqueous electrolyte according to claim 11, wherein the cyclic ester is a cyclic carbonate, and the cyclic carbonate is at least one selected from the group consisting of ethylene carbonate, propylene carbonate, and fluoroethylene carbonate.

13. The nonaqueous electrolyte according to claim 11, wherein the chain ester is a chain carbonate, and the chain carbonate is at least one selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, and methyl propyl carbonate.

14. A nonaqueous electrolyte battery comprising at least a positive electrode, a negative electrode, a separator, and the nonaqueous electrolyte according to claim 1 or 2.

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