Nonaqueous electrolyte solution, nonaqueous electrolyte battery, and method for producing nonaqueous electrolyte battery

Abstract

This nonaqueous electrolyte solution contains (I) a solute, (II) a nonaqueous organic solvent, (III) tris (1,1,1,3,3,3-hexafluoro-2-propyl) phosphite, and (IV) fluoroethylene carbonate. This nonaqueous electrolyte battery includes the nonaqueous electrolyte solution. This method for producing the nonaqueous electrolyte battery includes a step for injecting the nonaqueous electrolyte solution.

Description

Non-aqueous electrolyte, non-aqueous electrolyte battery, and method for manufacturing non-aqueous electrolyte battery

[0001] The present disclosure relates to a nonaqueous electrolyte, a nonaqueous electrolyte battery, and a method for manufacturing a nonaqueous electrolyte battery.

[0002] It is known that various additives are added to the nonaqueous electrolyte in order to improve the battery characteristics of the nonaqueous electrolyte battery.

[0003] Patent Document 1 discloses the use of a nonaqueous electrolyte solution containing a phosphite ester of a specific structure and a monofluorophosphate and / or a difluorophosphate simultaneously. Specifically, Example 11 of Patent Document 1 discloses a nonaqueous electrolyte solution containing 0.5 wt % tris(2,2,2-trifluoroethyl) phosphite, 0.5 wt % lithium difluorophosphate, and 0.5 wt % fluoroethylene carbonate, while Comparative Example 9 discloses a nonaqueous electrolyte solution containing 0.5 wt % tris(2,2,2-trifluoroethyl) phosphite and 0.5 wt % fluoroethylene carbonate.

[0004] Patent Document 2 discloses that by using a nonaqueous electrolyte solution simultaneously containing a phosphite ester of a specific structure and a carbonate having an unsaturated bond, a nonaqueous electrolyte secondary battery using a negative electrode containing a specific amount of SiOx or less maintains cycle characteristics while achieving an excellent balance between output characteristics and battery swelling. Specifically, Example 6 of Patent Document 2 discloses an example in which a nonaqueous electrolyte solution containing 0.5 mass% tris(2,2,2-trifluoroethyl)phosphite and 0.4 mass% vinylene carbonate is applied to a nonaqueous electrolyte secondary battery using a negative electrode containing 5.0 mass% SiOx.

[0005] Japanese Patent Application Publication No. 2011-049152 International Publication No. 2020 / 116601

[0006] The inventors' investigations have revealed that there is room for improvement in the high-temperature storage characteristics of nonaqueous electrolyte batteries equipped with a nonaqueous electrolyte containing a phosphite ester of a specific structure and fluoroethylene carbonate, as described in Example 11 and Comparative Example 9 of Patent Document 1, and nonaqueous electrolyte batteries equipped with a nonaqueous electrolyte containing tris(2,2,2-trifluoroethyl)phosphite and vinylene carbonate, as described in Example 6 of Patent Document 2.

[0007] Therefore, an object of the present disclosure is to provide a nonaqueous electrolyte, a nonaqueous electrolyte battery, and a method for manufacturing a nonaqueous electrolyte battery that exhibits good high-temperature storage characteristics.

[0008] [1] A non-aqueous electrolyte solution comprising (I) a solute, (II) a non-aqueous organic solvent, (III) tris(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite, and (IV) fluoroethylene carbonate. [2] The non-aqueous electrolyte solution according to [1], which is for a non-aqueous electrolyte battery having a negative electrode in which graphite and at least one selected from the group consisting of Si and Si metal oxides are used as negative electrode active materials. [3] The non-aqueous electrolyte solution according to [1], wherein (I) is LiPF ６ , LiBF ４ , LiSbF ６ , LiAsF ６ , LiClO ４ , LiN(FSO ２ ) ２ , LiAlO ２ , LiAlCl ４ [4] The nonaqueous electrolyte solution according to [1] or [2], wherein (I) is at least one selected from the group consisting of NaPF 6, LiCl 6, and LiI 6. ６ , NaBF ４ , NaSbF ６ , NaAsF ６ , NaClO ４ , NaN(FSO ２ ) ２ , NaAlO ２ , NaAlCl ４The nonaqueous electrolyte according to [1] or [2], wherein (II) is at least one selected from the group consisting of cyclic esters, chain esters, cyclic ethers, chain ethers, sulfone compounds, sulfoxide compounds, and ionic liquids. [5] The nonaqueous electrolyte according to any one of [1] to [4], wherein (II) comprises at least one selected from the group consisting of cyclic esters, chain esters, cyclic ethers, chain ethers, sulfone compounds, sulfoxide compounds, and ionic liquids. [6] The nonaqueous electrolyte according to [5], wherein the cyclic ester comprises a cyclic carbonate. [7] The nonaqueous electrolyte according to [6], wherein the cyclic carbonate comprises at least one selected from the group consisting of ethylene carbonate and propylene carbonate. [8] The nonaqueous electrolyte according to [5], wherein the chain ester comprises a chain carbonate. [9] The nonaqueous electrolyte according to [8], wherein the chain carbonate comprises at least one selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, and methyl propyl carbonate.

[10] The nonaqueous electrolyte solution according to [5], wherein the cyclic ether includes at least one selected from the group consisting of tetrahydrofuran, 2-methyltetrahydrofuran, furan, tetrahydropyran, 1,3-dioxane, 1,4-dioxane, 1,3-dioxolane, and trioxane.

[11] The chain ether is selected from the group consisting of diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, dimethoxymethane, trimethoxymethane, 1,The nonaqueous electrolyte solution according to [5], which contains at least one selected from the group consisting of 2-dimethoxyethane, diethoxyethane, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether.

[12] Further, cyclohexylbenzene, cyclohexylfluorobenzene, biphenyl, 2-fluorobiphenyl, tert-butylbenzene, tert-amylbenzene, 2-fluorotoluene, fluorobenzene, difluoroanisole, vinylene carbonate, vinylene carbonate oligomer (having a number average molecular weight of 170 to 5000 in terms of polystyrene), vinylethylene carbonate, divinylethylene carbonate, ethynylethylene carbonate, trans-difluoroethylene carbonate, methylpropargyl carbonate, ethylpropargyl carbonate, dipropargyl carbonate, dimethylvinylene carbonate, dimethyl dicarbonate, bis(1,1,1,3,3,3-hexafluoro-1-propyl)carbonate, bis(2,2,2-trifluoroethyl)carbonate, 1,6-diisocyanatohexane, maleic anhydride, anhydrous Organic acid anhydrides such as succinic acid, 1,4-dioxane-2,6-dione, glutaric anhydride, methanedisulfonic anhydride, 1,2-ethanedisulfonic anhydride, methanesulfonic anhydride, 2-sulfobenzoic anhydride, and 1,3-propanedisulfonic anhydride, 1,3-propanesulfonic anhydride, 1,3-propanesultone, 1,3-propenesultone, 1,4-butanesultone, 2,4-butanesultone, 1,3,2-dioxathiolane-2,2-dioxide, and 4-propyl -1,3,2-dioxathiolane-2,2-dioxide, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,3-dithiane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, methylenemethane disulfonate, dimethylenemethane disulfonate, trimethylenemethane disulfonate, methyl methanesulfonate, methanesulfonyl fluoride, ethenesulfonyl fluoride, N,N'-carbonylbis(N-methylsulfamoyl fluoride), difluoro(picolinato)borate, phenyl difluorophosphate, tripropargyl phosphate, tetrafluoro(picolinato)phosphate, (ethoxy)pentafluorocyclotriphosphazene, succinonitrile, methyldifluorovinylsilane, methylfluorodivinylsilane, dimethyldivinylsilane, trivinylmethylsilane, trivinylfluorosilane, tetravinylsilane, tris(trimethylsilyl)borate, tris(trimethylsilyl)phosphate, 1,3-dimethyl-1,3-divinyl-1,3-di(1,1,1,3,3,3-hexafluoroisopropyl)disiloxane, fluorosulfonate, trifluoromethanesulfonate, pentafluoroethanesulfonate, nonafluorobutanesulfonate, monomethyl sulfate, monoethyl sulfate, bis(trifluoromethanesulfonyl)imide salt, bis(pentafluoroethanesulfonyl)imide salt, (trifluoromethanesulfonyl)(nonafluorobutanesulfonyl)imide salt, (trifluoromethanesulfonyl)(pentafluoroethanesulfonyl)imide salt, (trifluoromethanesulfonyl)(fluorosulfonyl)imide salt, (pentafluoroethanesulfonyl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(trifluoromethanesulfonyl)imide salt, bis(difluorophosphoryl)imide salt, (fluorosulfonyl)(carbonyloxymethane

[12] The non-aqueous electrolyte solution according to any one of [1] to

[11] , containing at least one selected from the group consisting of (lithium sulfonate)imide salt, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, (carbonyldi(propargyl)phosphoryl)imide salt, monofluorophosphate, difluorophosphate, tetrafluoro(malonato)phosphate, tris(oxalato)phosphate, difluorobis(oxalato)phosphate, tetrafluorooxalatophosphate, bis(oxalato)borate, difluorooxalatoborate, difluoro(malonato)borate, tris(trifluoromethanesulfonyl)methide salt, tris(fluorosulfonyl)methide salt, acrylate, methacrylate, nitrate, nitrite, hexafluoroisopropanol, and trifluoroethanol.

[13] Furthermore, tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,

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

[12] , which contains at least one selected from the group consisting of 2-dioxide, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, nitrate, fluorosulfonate, and difluorophosphate.

[14] The non-aqueous electrolyte solution according to any one of [1] to

[13] , further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, fluorosulfonate, and difluorophosphate.

[15] The non-aqueous electrolyte solution according to any one of [1] to

[14] , further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, tetravinylsilane, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, and difluorophosphate.

[16] The non-aqueous electrolyte solution according to any one of [1] to

[14] , further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,The non-aqueous electrolyte solution according to any one of [1] to

[15] , further comprising at least one selected from the group consisting of trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,

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

[17] , further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (fluorosulfonyl)(carbonyloxymethanesulfonate lithium)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, nitrate, fluorosulfonate, and difluorophosphate.

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

[18] , further containing at least one selected from the group consisting of difluorobis(oxalato)phosphate, (difluorophosphoryl)(fluorosulfonyl)imide salt, (fluorosulfonyl)(carbonyloxymethanesulfonate lithium)imide, nitrate, and fluorosulfonate.

[20] A nonaqueous electrolyte battery comprising at least a positive electrode, a negative electrode, and the nonaqueous electrolyte solution according to any one of [1] to

[19] .

[21] A nonaqueous electrolyte battery comprising at least a positive electrode, a negative electrode containing graphite and at least one selected from the group consisting of Si and Si metal oxide as negative electrode active materials, and the nonaqueous electrolyte solution according to any one of [1] to

[19] .

[22] The nonaqueous electrolyte battery according to

[20] or

[21] , further comprising a separator.

[23] A method for producing a nonaqueous electrolyte battery, comprising a step of injecting the nonaqueous electrolyte solution according to any one of [1] to

[19] .

[0009] According to the present disclosure, it is possible to provide a nonaqueous electrolyte, a nonaqueous electrolyte battery, and a method for manufacturing a nonaqueous electrolyte battery that exhibit good high-temperature storage characteristics.

[0010] 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.

[0011] The present disclosure will be described in detail below, but the following description of the constituent elements is an example of an embodiment of the present disclosure, and the present disclosure is not limited to these specific contents.

[0012] 1. Regarding the Non-Aqueous Electrolyte The non-aqueous electrolyte of the present disclosure contains (I) a solute, (II) a non-aqueous organic solvent, (III) tris(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite, and (IV) fluoroethylene carbonate.

[0013] <Regarding (I) Solute> The solute (I) (also referred to as "(I)") contained in the nonaqueous electrolyte solution of the present disclosure will be described. The solute (I) can be any of various solutes that have been conventionally used in the field of such nonaqueous electrolyte solutions, without any particular limitations. Such a solute is preferably an ionic salt consisting of any pair of cation and anion. Various solutes can be used without any particular limitations as long as they exist in an ionic state as a cation and an anion in a nonaqueous organic solvent. Such a 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, and at least one anion selected from the group consisting of hexafluorophosphate anion, tetrafluoroborate anion, hexafluoroantimonate anion, hexafluoroarsenate anion, perchlorate anion, bis(fluorosulfonyl)imide anion, aluminate anion, tetrachloroaluminate anion, chloride ion, and iodide ion. Specifically, LiPF ６ , LiBF ４ , LiSbF ６ , LiAsF ６ , LiClO ４ , LiN(SO ２ F) ２ , LiAlO ２ , LiAlCl ４ , LiCl and LiI, or NaPF ６ , NaBF ４ , NaSbF ６, NaAsF ６ , NaClO ４ , NaN(SO ２ F) ２ , NaAlO ２ , NaAlCl ４ , NaCl, and NaI.

[0014] In particular, in consideration of the energy density, output characteristics, life, and the like of the nonaqueous electrolyte battery, it is preferable that the cation is at least one selected from the group consisting of lithium ions, sodium ions, potassium ions, magnesium ions, and quaternary ammonium cations, and that the anion is at least one selected from the group consisting of hexafluorophosphate anions, tetrafluoroborate anions, and bis(fluorosulfonyl)imide anions.

[0015] In the nonaqueous electrolyte solution of the present disclosure, as (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.

[0016] The concentration of (I) relative to the total amount of the nonaqueous electrolyte is not particularly limited. For example, the lower limit of the concentration of (I) may be 0.5 mol / L or more, 0.7 mol / L or more, or 0.9 mol / L or more. The upper limit of the concentration of (I) may be 5 mol / L or less, 4 mol / L or less, or 2 mol / L or less. A concentration of 0.5 mol / L or more is preferable because the ionic conductivity is less likely to decrease, and the cycle characteristics and output characteristics of the nonaqueous electrolyte battery are less likely to decrease. On the other hand, a concentration of 5 mol / L or less is preferable because the viscosity of the nonaqueous electrolyte is less likely to increase, and the ionic conductivity is less likely to decrease. Note that when two or more types of (I) are used, it is preferable that the total concentration of these solutes is in the above-mentioned range.

[0017] The temperature of the solution when (I) is dissolved in (II) the nonaqueous organic solvent is not particularly limited, but may be −20 to 80° C. or 0 to 60° C. Furthermore, the cation of the solute is more preferably a lithium ion when used in a lithium ion battery, and more preferably a sodium ion when used in a sodium ion battery.

[0018] <Regarding (II) Non-aqueous Organic Solvent> The non-aqueous organic solvent (II) (also referred to as "(II)") contained in the non-aqueous electrolyte solution of the present disclosure will be described. The type of non-aqueous organic solvent (II) is not particularly limited, and any non-aqueous organic solvent can be used. Such non-aqueous organic solvent preferably contains at least one selected from the group consisting of cyclic esters, chain esters, cyclic ethers, chain ethers, sulfone compounds, sulfoxide compounds, amide compounds, nitrile compounds, and ionic liquids, and more preferably contains at least one selected from the group consisting of cyclic esters, chain esters, cyclic ethers, chain ethers, sulfone compounds, sulfoxide compounds, and ionic liquids. Note that cyclic carbonates are a sub-concept of cyclic esters, and chain carbonates are a sub-concept of chain esters. Specific examples of the non-aqueous organic solvent (II) 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"), and butylene carbonate, as well as γ-butyrolactone and γ-valerolactone. Examples of chain esters include 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"), methyl propyl carbonate, ethyl propyl carbonate, methyl butyl carbonate, 2,2,2-trifluoroethyl methyl carbonate, 2,2,2-trifluoroethyl ethyl carbonate, and 2,2,2-trifluoroethyl propyl carbonate. In addition to chain carbonates such as 1,1,1,3,3,3-hexafluoro-1-propylmethyl carbonate, 1,1,1,3,3,3-hexafluoro-1-propylethyl carbonate, and 1,1,1,3,3,3-hexafluoro-1-propylpropyl carbonate, methyl acetate, ethyl acetate, methyl propionate, ethyl propionate (hereinafter sometimes referred to as "EP"), methyl 2-fluoropropionate, and ethyl 2-fluoropropionate.Examples of cyclic ethers include tetrahydrofuran, 2-methyltetrahydrofuran, furan, tetrahydropyran, 1,3-dioxane, 1,4-dioxane, 1,3-dioxolane, and trioxane. Examples of chain ethers include diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, dimethoxymethane, trimethoxymethane, 1,2-dimethoxyethane, diethoxyethane, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether. Other examples include sulfone compounds and sulfoxide compounds such as dimethyl sulfoxide and sulfolane, N,N-dimethylformamide, acetonitrile, and propionitrile. Other examples include ionic liquids.

[0019] The cyclic ester may include a cyclic carbonate, and the cyclic carbonate may include at least one selected from the group consisting of ethylene carbonate and propylene carbonate.

[0020] The chain ester may include a chain carbonate, and the chain carbonate may include at least one selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, and methyl propyl carbonate.

[0021] The cyclic ether may include at least one selected from the group consisting of tetrahydrofuran, 2-methyltetrahydrofuran, furan, tetrahydropyran, 1,3-dioxane, 1,4-dioxane, 1,3-dioxolane, and trioxane.

[0022] The chain ether may include at least one selected from the group consisting of diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, dimethoxymethane, trimethoxymethane, 1,2-dimethoxyethane, diethoxyethane, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether.

[0023] The nonaqueous electrolyte solution of the present disclosure may use one type of compound alone as (II), or two or more types of compounds may be mixed in any combination and ratio depending on the application. Among these, from the viewpoints of electrochemical stability against oxidation-reduction and chemical stability related to heat and reactions with the solute, it is particularly preferable to include at least one selected from the group consisting of PC, EC, DEC, DMC, and EMC.

[0024] Furthermore, it is preferable that the nonaqueous organic solvent contains, for example, one or more cyclic carbonates having a high dielectric constant and one or more chain carbonates or chain esters having a low liquid viscosity, since this increases the ionic conductivity of the electrolyte solution. Specifically, it is more preferable to use a nonaqueous organic solvent containing the following combinations: (1) Combination of EC and EMC, (2) Combination of EC and DEC, (3) Combination of EC, DMC and EMC, (4) Combination of EC, DEC and EMC, (5) Combination of EC, EMC and EP, (6) Combination of PC and DEC, (7) Combination of PC and EMC, (8) Combination of PC and EP, (9) Combination of PC, DMC and EMC, (10) Combination of PC, DEC and EMC, (11) Combination of PC, DEC and EP, (12) Combination of PC, EC and EMC, (13) Combination of PC, EC, DMC and EMC, (14) Combination of PC, EC, DEC and EMC, (15) Combination of PC, EC, EMC and EP

[0025] The concentration of the nonaqueous organic solvent in the present disclosure is not particularly limited as long as it functions as a nonaqueous organic solvent, but may be, for example, 40 to 99 mass %, preferably 50 to 95 mass %, and particularly preferably 70 to 93 mass %, relative to the total amount (100 mass %) of the nonaqueous electrolyte solution.

[0026] 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 may be 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. The content may also be 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 the load characteristics of the nonaqueous electrolyte battery to be easily maintained within good ranges.

[0027] Furthermore, 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 may be 1% by volume or more, preferably 2% by volume or more, more preferably 3% by volume or more, or 30% by volume or less, preferably 25% by volume or less, and more preferably 20% by volume or less. When propylene carbonate is contained in this range, for example, in the case of combining ethylene carbonate with a dialkyl carbonate, this is preferred because it maintains the properties of the combination of ethylene carbonate and a dialkyl carbonate while providing even better low-temperature properties.

[0028] 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 may be 15% by volume or more, preferably 20% by volume or more, more preferably 25% by volume or more, and may be 90% by volume or less, preferably 85% by volume or less, more preferably 80% by volume or less, based on 100% by volume of the nonaqueous organic solvent. By setting the content of the chain ester within the above range, the viscosity of the nonaqueous electrolyte can be set 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 set to good ranges. 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 set to good ranges. Furthermore, by combining a specific chain ester with ethylene carbonate at a specific content, battery performance can be significantly improved.

[0029] For example, when dimethyl carbonate, ethyl methyl carbonate, or a mixture of dimethyl carbonate and ethyl methyl carbonate is selected as the specific chain ester, the content of ethylene carbonate is not particularly limited and may be any content as long as it does not significantly impair the effects of the present disclosure, but may be 5% by volume or more, preferably 10% by volume or more, or 45% by volume or less, preferably 40% by volume or less. The content of dimethyl carbonate may be 20% by volume or more, preferably 30% by volume or more, or 50% by volume or less, preferably 45% by volume or less. The content of ethyl methyl carbonate may be 20% by volume or more, preferably 30% by volume or more, or 50% by volume or less, preferably 45% by volume or less. By setting the content within the above range, the low-temperature deposition temperature of the electrolyte is lowered, while also reducing the viscosity of the nonaqueous electrolyte, improving ionic conductivity and making it easier to obtain high input / output even at low temperatures.

[0030] 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. It may be 1% by volume or more, preferably 2% by volume or more, more preferably 3% by volume or more, or 30% by volume or less, preferably 25% by volume or less, more preferably 20% by volume or less, based on 100% by volume of the nonaqueous organic solvent. If the content of the chain ether is within the above range, for example, in the case of a lithium-ion battery in which the cation is mainly lithium, 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-intercalation of the chain ether with lithium ions can be suppressed, making it easier to maintain the input / output characteristics and charge / discharge rate characteristics within appropriate ranges.

[0031] 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 may be 0.3 vol% or more, preferably 0.5 vol% or more, more preferably 1 vol% or more, and may be 40 vol% or less, preferably 35 vol% or less, more preferably 30 vol% or less, relative to 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 make it easy to keep the input / output characteristics and charge / discharge rate characteristics of the nonaqueous electrolyte battery within appropriate ranges.

[0032] <Regarding (III)> The following will explain (III) tris(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite (also referred to as "(III)" or "THFIPPi") contained in the nonaqueous electrolyte solution of the present disclosure. The structural formula of THFIPPi is shown below.

[0033]

[0034] The content of (III) in the nonaqueous electrolyte solution of the present disclosure may be 0.005% by mass or more and 8% by mass or less, 0.01% by mass or more and 3% by mass or less, or 0.05% by mass or more and 2% by mass or less, relative to the total amount of the nonaqueous electrolyte solution.

[0035] <Regarding (IV)> The (IV) fluoroethylene carbonate (also referred to as "(IV)" or "FEC") contained in the nonaqueous electrolyte solution of the present disclosure will be described. The content of (IV) in the nonaqueous electrolyte solution of the present disclosure may be 0.01% by mass or more and 10% by mass or less, 0.1% by mass or more and 9% by mass or less, or 0.2% by mass or more and 8% by mass or less, relative to the total amount of the nonaqueous electrolyte solution. In one preferred embodiment, the content of (IV) relative to the total amount of the nonaqueous electrolyte solution is 0.1% by mass or more and 9% by mass or less, and the content of (III) relative to the total amount of the nonaqueous electrolyte solution is 0.01% by mass or more and 3% by mass or less.

[0036] <Regarding (IV) / (III)> In the nonaqueous electrolyte solution of the present disclosure, the mass ratio of (III) to (IV), (IV) / (III), is not particularly limited, but may be 0.8 or more, 1.0 or more, or 1.5 or more. In addition, (IV) / (III) may be 1000 or less, 100 or less, or 50 or less.

[0037] <Regarding Other Components> The nonaqueous electrolyte solution of the present disclosure is composed of the above-mentioned components as basic constituents, but the nonaqueous electrolyte solution of the present disclosure may contain the components described below (hereinafter also referred to as "other components that may be contained" or "other components") in any combination and ratio, as long as the gist of the present disclosure is not impaired. As the other components, for example, other additives commonly used in this technical field may be added in any ratio.

[0038] Other components include, for example, aromatic compounds such as cyclohexylbenzene, cyclohexylfluorobenzene, biphenyl, 2-fluorobiphenyl, tert-butylbenzene, tert-amylbenzene, 2-fluorotoluene, fluorobenzene, and difluoroanisole, vinylene carbonate (hereinafter sometimes referred to as "VC"), vinylene carbonate oligomers (having a number average molecular weight of 170 to 5000 in terms of polystyrene), vinylethylene carbonate, divinylethylene carbonate, ethynylethylene carbonate, tra Carbonate compounds such as ns-difluoroethylene carbonate, methyl propargyl carbonate, ethyl propargyl carbonate, dipropargyl carbonate, dimethylvinylene carbonate, dimethyl dicarbonate, bis(1,1,1,3,3,3-hexafluoro-1-propyl)carbonate, and bis(2,2,2-trifluoroethyl)carbonate; isocyanate compounds such as 1,6-diisocyanatohexane; maleic anhydride, succinic anhydride, 1,4-dioxane-2,6-dione, glutaric anhydride, and methanedisulfonic acid anhydride, organic acid anhydrides such as 1,2-ethanedisulfonic anhydride, methanesulfonic anhydride, 2-sulfobenzoic anhydride, and 1,3-propanedisulfonic anhydride, 1,3-propanesulfonic anhydride, 1,3-propanesultone, 1,3-propenesultone, 1,4-butanesultone, 2,4-butanesultone, 1,3,2-dioxathiolane-2,2-dioxide, 4-propyl-1,3,2-dioxathiolane-2,2-dioxide, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,3-dithiane-1,1,3,3-tetraoxide, and 1,2-oxathiolane-5-one sulfonate compounds and sulfonyl compounds such as methyl methyl ether-2,2-dioxide, methylenemethane disulfonate, dimethylmethane disulfonate, trimethylenemethane disulfonate, methyl methanesulfonate, methanesulfonyl fluoride, ethenesulfonyl fluoride, and N,N'-carbonylbis(N-methylsulfamoyl fluoride); borate compounds such as difluoro(picolinato)borate; phosphate compounds such as phenyl difluorophosphate, tripropargyl phosphate, and tetrafluoro(picolinato)phosphate;Phosphazene compounds such as (ethoxy)pentafluorocyclotriphosphazene, nitrile compounds such as succinonitrile, silane compounds such as methyldifluorovinylsilane, methylfluorodivinylsilane, dimethyldivinylsilane, trivinylmethylsilane, trivinylfluorosilane, tetravinylsilane, tris(trimethylsilyl)borate, and tris(trimethylsilyl)phosphate, siloxane compounds such as 1,3-dimethyl-1,3-divinyl-1,3-di(1,1,1,3,3,3-hexafluoroisopropyl)disiloxane, fluoro sulfonates such as sulfonates, trifluoromethanesulfonates, pentafluoroethanesulfonates, and nonafluorobutanesulfonates (among which, fluorosulfonates and trifluoromethanesulfonates are preferred); monoalkyl sulfates such as monomethyl sulfate and monoethyl sulfate; bis(trifluoromethanesulfonyl)imide salts, bis(pentafluoroethanesulfonyl)imide salts, (trifluoromethanesulfonyl)(nonafluorobutanesulfonyl)imide salts, (trifluoromethanesulfonyl)(pentafluoroethanesulfonyl)imide salts; imide salt, (trifluoromethanesulfonyl)(fluorosulfonyl)imide salt, (pentafluoroethanesulfonyl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(trifluoromethanesulfonyl)imide salt, bis(difluorophosphoryl)imide salt, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide salt, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, (carbonyldi(propargyl)phosphoryl)imide salt , (among which, preferably, imide salts such as bis(trifluoromethanesulfonyl)imide salt, (trifluoromethanesulfonyl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(trifluoromethanesulfonyl)imide salt, and bis(difluorophosphoryl)imide salt, or imide compounds in which a hydrogen atom is bonded to a nitrogen atom instead of a cation in the above imide salts, monofluorophosphates, difluorophosphates, tetrafluoro(malonato)phosphates, tris(oxalato)phosphates,Examples of suitable salts include phosphates such as difluorobis(oxalato)phosphate and tetrafluorooxalatophosphate, borates such as bis(oxalato)borate, difluorooxalatoborate and difluoro(malonato)borate, methide salts such as tris(trifluoromethanesulfonyl)methide salt and tris(fluorosulfonyl)methide salt, carboxylates such as acrylates and methacrylates, inorganic salts such as nitrates and nitrites, and fluorine-containing alcohols such as hexafluoroisopropanol and trifluoroethanol. The cation in the above salts may be an alkali metal ion, an alkaline earth metal ion, or a quaternary ammonium.

[0039] The nonaqueous electrolyte solution of the present disclosure may further contain the following compounds in order to improve the cycle capacity retention rate and gas generation during cycle testing.

[0040]

[0041] The nonaqueous electrolyte solution of the present disclosure may further include cyclohexylbenzene, cyclohexylfluorobenzene, biphenyl, 2-fluorobiphenyl, tert-butylbenzene, tert-amylbenzene, 2-fluorotoluene, fluorobenzene, difluoroanisole, vinylene carbonate, vinylene carbonate oligomer (having a number average molecular weight of 170 to 5000 in terms of polystyrene), vinylethylene carbonate, divinylethylene carbonate, ethynylethylene carbonate, trans-difluoroethylene carbonate, methylpropargyl carbonate, ethylpropargyl carbonate, dipropargyl carbonate, dimethylvinylene carbonate, dimethyldicarbonate, bis(1,1,1,3,3,3-hexafluoro-1-propyl)carbonate, bis(2,2,2-trifluoroethyl)carbonate, 1,6-diisocyanatohexane, Maleic anhydride, succinic anhydride, 1,4-dioxane-2,6-dione, glutaric anhydride, methanedisulfonic anhydride, 1,2-ethanedisulfonic anhydride, methanesulfonic anhydride, 2-sulfobenzoic anhydride, 1,3-propanedisulfonic anhydride, 1,3-propanesulfonic anhydride, 1,3-propanesultone, 1,3-propenesultone, 1,4-butanesultone, 2,4-butanesultone, 1,3,2-dioxathiolane-2,2-dioxide, 4-propion 1,3,2-dioxathiolane-2,2-dioxide, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,3-dithiane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, methylenemethane disulfonate, dimethylenemethane disulfonate, trimethylenemethane disulfonate, methyl methanesulfonate, methanesulfonyl fluoride, ethenesulfonyl fluoride, N,N'-carbonylbis(N-methylsulfamoyl fluoride), difluoro(picolinato)borate, phenyl difluorophosphate, tripropargyl phosphate, tetrafluoro(picolinato)phosphate, (ethoxy)pentafluorocyclotriphosphazene, succinonitrile, methyldifluorovinylsilane, methylfluorodivinylsilane, dimethyldivinylsilane, trivinylmethylsilane, trivinylfluorosilane, tetravinylsilane, tris(trimethylsilyl)borate, tris(trimethylsilyl)phosphate, 1,3-dimethyl-1,3-divinyl-1,3-di(1,1,1,3,3,3-Hexafluoroisopropyl)disiloxane, fluorosulfonate, trifluoromethanesulfonate, pentafluoroethanesulfonate, nonafluorobutanesulfonate, monomethyl sulfate, monoethyl sulfate, bis(trifluoromethanesulfonyl)imide salt, bis(pentafluoroethanesulfonyl)imide salt, (trifluoromethanesulfonyl)(nonafluorobutanesulfonyl)imide salt, (trifluoromethanesulfonyl)(pentafluoroethanesulfonyl)imide salt, (trifluoromethanesulfonyl)(fluorosulfonyl)imide salt, (pentafluoroethanesulfonyl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(trifluoromethanesulfonyl)imide salt, bis(difluorophosphoryl)imide salt, (fluorosulfonyl)(calcium Preferably, the catalyst contains at least one selected from the group consisting of (lithium 2-propenyloxymethanesulfonate)imide salt, (fluorosulfonyl)(carbonyloxymethanesulfonate)imide salt, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, (carbonyldi(propargyl)phosphoryl)imide salt, monofluorophosphate, difluorophosphate, tetrafluoro(malonato)phosphate, tris(oxalato)phosphate, difluorobis(oxalato)phosphate, tetrafluorooxalatophosphate, bis(oxalato)borate, difluorooxalatoborate, difluoro(malonato)borate, tris(trifluoromethanesulfonyl)methide salt, tris(fluorosulfonyl)methide salt, acrylate, methacrylate, nitrate, nitrite, hexafluoroisopropanol, and trifluoroethanol.

[0042] In terms of the capacity retention rate in an 80°C storage test described below, among other components, tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyloxymethanesulfonate lithium)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl) It is preferable that at least one selected from the group consisting of imide salts, fluorosulfonates, and difluorophosphates is further included, and it is more preferable that at least one selected from the group consisting of tetrafluorooxalatophosphates, difluorobis(oxalato)phosphates, tetravinylsilane, (difluorophosphoryl)(fluorosulfonyl)imide salts, tripropargyl phosphate, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salts, and difluorophosphates is further included.

[0043] From the viewpoint of the amount of gas generated in the 80°C storage test described later, among other components, tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-pro Preferably, the compound further comprises at least one selected from the group consisting of trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salts, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salts, and difluorophosphate salts. More preferably, the compound further comprises at least one selected from the group consisting of trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salts, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salts, and difluorophosphate salts.

[0044] From the viewpoint of the capacity retention rate in a 25°C cycle test described below, among other components, it is preferable that at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, nitrate, fluorosulfonate, and difluorophosphate is further contained, and it is more preferable that at least one selected from the group consisting of difluorobis(oxalato)phosphate, (difluorophosphoryl)(fluorosulfonyl)imide salt, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, nitrate, and fluorosulfonate is further contained.

[0045] By adding the above-mentioned other components to the nonaqueous electrolyte solution of the present disclosure, at least one of the overcharge prevention effect, the negative electrode film formation effect, and the positive electrode protection effect may be enhanced.

[0046] In addition, the electrolyte for a non-aqueous electrolyte battery may be quasi-solidified with a gelling agent or a crosslinked polymer, as in the case of a non-aqueous electrolyte battery known as a lithium polymer battery. Examples of the polymer include a polymer having polyethylene oxide in the main chain or side chain, a homopolymer or copolymer of polyvinylidene fluoride, a methacrylic acid ester polymer, and polyacrylonitrile.

[0047] When the non-aqueous electrolyte solution of the present disclosure contains other components, the content of the other components may be 0.01% by mass or more and 10% by mass or less with respect to the total amount of the non-aqueous electrolyte solution.

[0048] Furthermore, the content of bis(trifluoromethanesulfonyl)imide salt, trifluoromethanesulfonate salt, and nonafluorobutanesulfonate salt relative to the total amount of the nonaqueous electrolyte may be 0.01 mass % or more and 20 mass % or less.

[0049] Furthermore, the content of bis(1,1,1,3,3,3-hexafluoro-1-propyl) carbonate and bis(2,2,2-trifluoroethyl) carbonate relative to the total amount of the nonaqueous electrolyte may be 0.1 mass % or more and 70 mass % or less.

[0050] Furthermore, when the other component is an ionic salt, the cation is more preferably a lithium ion when used in a lithium ion battery, and more preferably a sodium ion when used in a sodium ion battery.

[0051] The nonaqueous electrolyte solution of the present disclosure may contain a total of four or more alkali metal salts by using multiple types of salt compounds of the solutes (lithium salts, sodium salts, etc.) and other components, depending on the required properties, or may contain a total of five or more alkali metal salts.

[0052] The nonaqueous electrolyte solution of the present disclosure is suitable for use in nonaqueous electrolyte batteries (preferably nonaqueous electrolyte secondary batteries). Use of the nonaqueous electrolyte solution of the present disclosure in a nonaqueous electrolyte battery can improve the high-temperature storage characteristics of the nonaqueous electrolyte battery. Furthermore, use of the nonaqueous electrolyte solution of the present disclosure in a nonaqueous electrolyte battery preferably reduces the amount of gas generated when the nonaqueous electrolyte battery is stored at high temperatures (80°C). Furthermore, it is preferable that the capacity retention rate after a cycle test at 25°C can be increased. The nonaqueous electrolyte solution of the present disclosure is preferably a nonaqueous electrolyte solution for a nonaqueous electrolyte battery equipped with a negative electrode (hereinafter sometimes referred to as a "Si negative electrode") containing graphite and at least one selected from the group consisting of Si and Si metal oxides as negative electrode active materials.

[0053] 2. Regarding the Non-Aqueous Electrolyte Battery The non-aqueous electrolyte battery of the present disclosure includes at least a positive electrode, a negative electrode, and the non-aqueous electrolyte of the present disclosure. The non-aqueous electrolyte battery of the present disclosure has good high-temperature storage characteristics. Furthermore, the non-aqueous electrolyte battery of the present disclosure preferably generates little gas when stored at high temperatures (80°C). Furthermore, it preferably has a high capacity retention rate after a cycle test at 25°C. The non-aqueous electrolyte battery of the present disclosure preferably includes at least the non-aqueous electrolyte of the present disclosure, a negative electrode containing graphite and at least one selected from the group consisting of Si and Si metal oxides as negative electrode active materials, and a positive electrode. The battery may further include a separator, an exterior body, etc. Alternatively, a solid electrolyte may be used as a medium for impregnating the non-aqueous electrolyte instead of the separator. The nonaqueous electrolyte battery of the present disclosure preferably includes at least a positive electrode, a negative electrode (which may include, as negative electrode active materials, at least one selected from the group consisting of Si and a Si metal oxide and graphite), a separator, and the nonaqueous electrolyte of the present disclosure. The nonaqueous electrolyte battery of the present disclosure is preferably a nonaqueous electrolyte secondary battery.

[0054] [Negative Electrode] [Negative Electrode Active Material] The negative electrode active material is not particularly limited, but may be a material capable of reversibly inserting and extracting alkali metal ions, such as lithium ions and sodium ions, or alkaline earth metal ions. Among these, it is preferable to use at least one selected from the group consisting of Si and a Si metal oxide, and graphite. Specifically, the negative electrode active material in the present disclosure preferably contains at least one selected from the group consisting of Si and a Si metal oxide, and graphite. The Si metal oxide is a compound represented by SiOx, where x has a value of 0.5 to 1.5. The negative electrode active material may contain silicon metal or may contain Si metal oxide (SiOx). The total content of at least one selected from the group consisting of Si and Si metal oxides contained in the negative electrode active material may be 0.1 to 50 mass %, and preferably 0.1 to 30 mass %, when the total amount of the at least one selected from the group consisting of Si and Si metal oxides contained in the negative electrode active material and graphite is taken as 100 mass %.

[0055] As the graphite contained in the negative electrode active material, various types of artificial graphite and natural graphite are used. Graphite exhibits very little change in its crystalline structure due to the absorption and desorption of lithium, resulting in high energy density and excellent cycle characteristics. The shape of the graphite may be fibrous, spherical, granular, or flaky. Furthermore, amorphous carbon or graphite coated with amorphous carbon is more preferred because it reduces the reactivity between the material surface and the electrolyte. When graphite is used in particulate form, its particle size may be, for example, 5 to 30 μm, preferably 8 to 15 μm, in terms of average particle size d50. In the case of a lithium-ion battery in which the cations in the nonaqueous electrolyte are mainly lithium, the graphite is capable of doping and dedoping lithium ions. Examples include graphite with an X-ray diffraction lattice plane (002 plane) d value of 0.340 nm or less, and graphite with an X-ray diffraction lattice plane (002 plane) d value of more than 0.340 nm. These negative electrode active materials can be used alone or in combination of two or more.

[0056] [Negative Electrode Current Collector] The negative electrode has a negative electrode current collector. For example, copper, stainless steel, nickel, titanium, or alloys thereof can be used as the negative electrode current collector. For sodium ion batteries, aluminum or its alloys can also be used.

[0057] [Negative Electrode Active Material Layer] The negative electrode has, for example, a negative electrode active material layer formed on at least one surface of a negative electrode current collector. The negative electrode active material layer is composed of, for example, the above-mentioned negative electrode active material, a binder, and, if necessary, a conductive agent. Examples of the binder include polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, styrene butadiene rubber (hereinafter also referred to as "SBR"), carboxymethyl cellulose, methyl cellulose, cellulose acetate phthalate, hydroxypropyl methyl cellulose, polyvinyl alcohol, and polyimide. Examples of the conductive agent that can be used include carbon materials such as acetylene black, ketjen black, furnace black, carbon fiber, graphite, and fluorinated graphite.

[0058] [Positive Electrode] 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.

[0059] [Positive Electrode Active Material] For example, when the cation is lithium, the positive electrode material (positive electrode active material) is LiCoO ２ , LiNiO ２ , LiMnO ２ , LiMn ２ O ４ Lithium-containing transition metal composite oxides such as Li[Ni], Li[Ni], Co[Ni], Mn[Ni], Ni[Ni], Co[Ni], Mn[Ni], Ni[Ni], Co[Ni], Mn[Ni], Ni[Ni], Co[Ni], Mn[Ni], Ni[Ni], Mn[Ni], Co[Ni], Mn[Ni], Ni[Ni], Mn[Ni], Co[Ni], Mn[Ni], Mn[Ni], Ni[Ni], Mn ... １／３ Mn １／３ Co １／３ ]O ２ , Li[Ni ０．４５ Mn ０．３５ Co ０．２ ]O２ , 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, may be 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 ０．８７ Co 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、 LiNi ０．５ Mn １．５ O ４、 LiNi ０．５ Mn ０．５ O4] ２、 LiNi ０．１ Mn １．９ (This seems to be a duplicate tag, should it be ４、 ?) O ４、 01]]LiCo ０．５ Mn ０．５ O ２ , 0.5[LiNi ０．５ [[ID=]09]]Mn ０．５ O ２ ·0.5[Li ２ MnO ３ , 0.5[LiNi １／３ Co １／３ Mn１／３ O ２ ] 0.5 [Li ２ MnO ３ ], 0.5[LiNi ０．３７５ Co ０．２５ Mn ０．３７５ O ２ ] 0.5 [Li ２ MnO ３ ], 0.5[LiNi ０．３７５ Co ０．１２５ Fe ０．１２５ Mn ０．３７５ O ２ ] 0.5 [Li ２ MnO ３ ], 0.45[LiNi ０．３７５ Co ０．２５ Mn ０．３７５ O ２ ] 0.10 [Li ２ TiO ３ ] 0.45 [Li ２ MnO ３ In addition, Li, which is called olivine, α M ００１ P.O. ４ A compound represented by (0<α≦1) may also be used. ００１ is at least one element selected from the group consisting of Mn, Fe, Co, and Ni. ００１ From the viewpoint of battery capacity and cycle characteristics, M preferably contains Fe, Mn, or both Fe and Mn, and more preferably contains Fe or both Fe and Mn. ００１ A part of the elements may be substituted with other elements such as Mg, Al, Ti, V, Cr, and Zr. The olivine-type positive electrode active material may have, on a part or all of the particle surface, a simple substance or a compound containing one or more elements selected from the group consisting of B, C, N, F, Na, Mg, Al, Si, P, S, Cl, K, Ca, Ti, Zn, Zr, and W. Specifically, LiFePO ４ , LiCoPO ４ , LiMnPO ４ , LiNiPO ４ , LiFe ０．５ Mn ０．５ P.O. ４ , LiFe ０．４ Mn ０．６ P.O.４ , LiFe ０．３ Mn ０．７ P.O. ４ , LiFe ０．５ Mn ０．４ Mg ０．１ P.O. ４ , LiFe ０．５ Mn ０．４５ Zr ０．０５ P.O. ４ Further, phosphate compounds of transition metals such as TiO ２ , V ２ O ５ , MoO ３ oxides such as TiS ２ , FeS, MoS ２ Alternatively, sulfides such as polyacetylene, polyparaphenylene, polyaniline, and polypyrrole, conductive polymers such as activated carbon, radical-generating polymers, and carbon materials may be used.

[0060] 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 ２sodium-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 (SO ４ ) ３ Polyanion type compounds such as those of the formula Na β M ００２ γ [Fe(CN) ６ ] δ The sodium salt of a Prussian blue analogue represented by ００２ = Cr, Mn, Fe, Co, Ni, Cu or Zn, and 0≦β≦2, 0.5≦γ≦1.5, 0.5≦δ≦1.5), TiO ２ , V ２ O ５ , MoO ３ oxides such as TiS ２ , FeS, MoS ２ Alternatively, sulfides such as polyacetylene, polyparaphenylene, polyaniline, and polypyrrole, conductive polymers such as activated carbon, radical-generating polymers, and carbon materials may be used.

[0061] [Positive Electrode Current Collector] The positive electrode has a positive electrode current collector. As the positive electrode current collector, for example, aluminum, stainless steel, nickel, titanium, or an alloy thereof can be used.

[0062] [Positive Electrode Active Material Layer] The positive electrode comprises, for example, a positive electrode active material layer formed on at least one surface of a positive electrode current collector. The positive electrode active material layer is composed of, for example, the above-mentioned positive electrode active material, a binder, and, if necessary, a conductive agent. Examples of the binder include those described in [Negative Electrode Active Material Layer]. Examples of the conductive agent include carbon materials such as acetylene black, ketjen black, furnace black, carbon fiber, graphite (granular graphite or flake graphite), and fluorinated graphite. For the positive electrode, it is preferable to use acetylene black or ketjen black, which have low crystallinity.

[0063] [Method for producing electrodes (positive and negative electrodes)] The electrodes can be obtained, for example, by dispersing and kneading predetermined amounts of an active material, a binder, and, if necessary, a conductive agent in a solvent such as N-methyl-2-pyrrolidone (hereinafter sometimes referred to as "NMP") or water, and then applying the resulting paste to a current collector and drying it to form an active material layer. The resulting electrode is preferably compressed by a method such as a roll press to adjust it to an electrode with an appropriate density.

[0064] [Separator] The nonaqueous electrolyte battery of the present disclosure may include a separator. Examples of separators used to prevent contact between the positive electrode and the negative electrode include nonwoven fabrics or porous sheets made of polyolefins such as polypropylene and polyethylene, cellulose, paper, or glass fiber. These films are preferably microporous so that the electrolyte can penetrate and ions can easily pass through. Examples of polyolefin separators include microporous polymer films such as porous polyolefin films, which electrically insulate the positive electrode and negative electrode and are permeable to lithium ions. Specific examples of porous polyolefin films include porous polyethylene films alone, or multilayer films formed by stacking porous polyethylene films and porous polypropylene films. Other examples include composite films of porous polyethylene and polypropylene films. The nonaqueous electrolyte of the present disclosure may be impregnated into the separator and retained therein. There are no particular limitations on the impregnation method, and any known method may be used. Specifically, the electrolyte can be finally injected into a battery equipped with a positive electrode, a separator, and a negative electrode to impregnate the battery.

[0065] [Exterior Body] As the exterior body of the nonaqueous electrolyte battery of the present disclosure, for example, a coin-shaped, cylindrical, or rectangular metal can, or even a laminate exterior body, etc. Suitable metal can materials include, for example, nickel-plated steel, stainless steel, nickel-plated stainless steel, aluminum or its alloy, nickel, titanium, etc. As the laminate exterior body, for example, an aluminum laminate film, a SUS laminate film, or a laminate film of silica-coated polypropylene, polyethylene, etc., can be used.

[0066] The configuration of the nonaqueous electrolyte battery according to this embodiment is not particularly limited, and may be, for example, a configuration in which an electrode element in which a positive electrode and a negative electrode are arranged opposite each other and a nonaqueous electrolyte are enclosed in an exterior body. The shape of the nonaqueous electrolyte battery is not particularly limited, and an electrochemical device having a shape such as a coin, a cylinder, a square, or an aluminum laminate sheet can be assembled from the above components. In one embodiment, for example, a nonaqueous electrolyte battery containing the nonaqueous electrolyte of the present disclosure can be manufactured by impregnating a separator with the nonaqueous electrolyte, disposing the separator between a positive electrode having at least one selected from the group consisting of nickel-containing oxides and phosphates as a positive electrode active material, and a negative electrode having at least one selected from the group consisting of Si and Si metal oxides and graphite as a negative electrode active material, and assembling the separator.

[0067] 3. Method for Manufacturing a Non-Aqueous Electrolyte Battery The method for manufacturing a non-aqueous electrolyte battery according to the present disclosure includes a step of injecting the non-aqueous electrolyte according to the present disclosure. The method for injecting the electrolyte is not particularly limited, and can be a conventional method. For example, vacuum injection can be used.

[0068] The present disclosure will be specifically described below using examples, but the present disclosure is not limited to such examples.

[0069] [Preparation of non-aqueous electrolyte solutions in examples and comparative examples] [Comparative example 0] EC, DMC, and EMC were used as (II) and mixed in a volume ratio of EC:DMC:EMC = 3:3:4. Then, LiPF was used as (I). ６ was added and dissolved in the non-aqueous electrolyte solution so that the content thereof became 1.0 mol / L, thereby preparing a comparative non-aqueous electrolyte solution 0.

[0070] [Example 1-1, Comparative Examples 1-1 to 1-6] Non-aqueous electrolyte solutions and comparative non-aqueous electrolyte solutions shown in Table 1 were prepared in the same manner as in Comparative Non-aqueous Electrolyte Solution 0, except that the compounds shown in Table 1 were added and dissolved as (III) and (IV) to the contents shown in Table 1.

[0071] [Examples 1-2 to 1-16, Comparative Examples 1-7] Non-aqueous electrolyte solutions and comparative non-aqueous electrolyte solutions shown in Table 2 were prepared in the same manner as in the preparation of comparative non-aqueous electrolyte solution 0, except that compounds shown in Table 2 were added and dissolved as components (III), (IV), and other components to the amounts shown in Table 2.

[0072] [Preparation of NCM811 positive electrode] Li[Ni ０．８ Mn ０．１ Co ０．１ ]O ２ 92.0% by mass of the powder was mixed with 3.5% by mass of polyvinylidene fluoride (hereinafter also referred to as "PVDF") as a binder and 4.5% by mass of acetylene black as a conductive material, and NMP was further added to prepare a cathode composite paste. 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 cathode.

[0073] [Preparation of Silicon-Containing Graphite Negative Electrode (SiO-Gr.)] 83% by mass of artificial graphite powder was mixed with 10% by mass of SiOx (x = 1, manufactured by Osaka Titanium Technologies Co., Ltd.), 3% by mass of conductive material (manufactured by Denka, HS-100), 1% by mass of carbon nanofiber (manufactured by Showa Denko, VGCF), 2% by mass of styrene butadiene rubber (hereinafter also referred to as "SBR"), and 1% by mass of sodium carboxymethyl cellulose (hereinafter also referred to as "CMC"), and water was added to prepare a negative electrode composite paste. This paste was applied to copper foil, dried, pressed, and then punched out to 4.5 cm x 5.5 cm to obtain a test silicon-containing graphite negative electrode. In the following tables, the active material of the negative electrode is referred to as "SiO-Gr."

[0074] [Preparation of Non-Aqueous Electrolyte Battery (hereinafter also referred to simply as "Cell")] In an argon atmosphere with a dew point of -50°C or less, a terminal was welded to the above-mentioned NCM811 positive electrode, and then a polyethylene separator (5 cm x 6 cm) was placed on each side. Furthermore, a silicon-containing graphite negative electrode (SiO-Gr.) with a terminal previously welded was placed on each side so that the separator was sandwiched between the positive electrode and the negative electrode, with the negative electrode active material surface facing the positive electrode active material surface. This assembly was placed in an aluminum laminate bag with an opening on one side. The non-aqueous electrolyte solution and comparative non-aqueous electrolyte solution listed in Tables 1 and 2 were vacuum-injected into the bag, and the opening was then heat-sealed to prepare aluminum laminate-type non-aqueous electrolyte batteries according to the examples and comparative examples listed in Tables 1 and 2.

[0075] [Evaluation Conditions] <Initial Charge / Discharge> Each cell prepared as described above was allowed to stand for 12 hours (impregnation time: 12 hours) at an ambient temperature of 25° C., and then conditioned under the following conditions at an ambient temperature of 25° C. That is, as the initial charge / discharge, the cell was charged at a constant current / constant voltage of 0.1 C rate (9 mA) to an upper charge voltage of 4.3 V, discharged at a constant current / constant voltage of 0.2 C rate to a discharge cut-off voltage of 2.7 V, and then charged at a constant current / constant voltage of 0.2 C rate to an upper charge voltage of 4.3 V, and discharged at a constant current / constant voltage of 0.2 C rate to a discharge cut-off voltage of 2.7 V, and this charge / discharge cycle was repeated three times.

[0076] <High-Temperature (80°C) Storage Characteristic Test> The cells subjected to the above conditioning were charged at a constant current and constant voltage of 0.2C rate to a maximum charge voltage of 4.3V at an ambient temperature of 25°C, and then stored in an 80°C environment for 10 days. After the above storage test, the cells were discharged at a constant current and constant voltage of 0.2C rate to a discharge cut-off voltage of 2.7V at an ambient temperature of 25°C, charged at a constant current and constant voltage of 0.2C rate to a maximum charge voltage of 4.3V using a constant current and constant voltage method, and discharged at a constant current and constant voltage of 0.2C rate to a discharge cut-off voltage of 2.7V, and the discharge capacity was measured. This discharge capacity was designated as the "discharge capacity after 10 days of storage." The "80°C storage test capacity retention rate" was calculated using the following formula. The discharge capacity in the final cycle of the above conditioning was designated as the initial discharge capacity. 80°C storage test capacity retention rate (%) = (discharge capacity after 10 days of storage / initial discharge capacity) × 100

[0077] Before and after the high-temperature storage characteristic evaluation, the cell volume was measured by the Archimedes method using silicone oil (silicone oil KF54, manufactured by Shin-Etsu Chemical Co., Ltd.), and the gas generation amount V (unit: cm) during the 80°C storage test was calculated. ３ ) (gas generation amount V = cell volume V2 after high-temperature storage characteristic evaluation - cell volume V1 before high-temperature storage characteristic evaluation) was calculated. Based on this gas generation amount V, the "gas generation amount in 80°C storage test" was evaluated.

[0078] <Cycle Characteristics Test> A charge / discharge test was conducted at an ambient temperature of 25°C on the cells that had undergone the conditioning described above, and the cycle characteristics were evaluated. A charge / discharge cycle was repeated at a current value of 90 mA using a constant current / constant voltage method, with an upper charge voltage limit of 4.3 V and a lower discharge voltage limit of 2.7 V. The degree of cell deterioration was evaluated based on the discharge capacity retention rate at the 400th cycle in the charge / discharge test at an ambient temperature of 25°C. The "25°C cycle test capacity retention rate," expressed as the discharge capacity retention rate at the 400th cycle, was calculated using the following formula. The discharge capacity at the first cycle in the charge / discharge test at an ambient temperature of 25°C was defined as the initial discharge capacity. 25°C cycle test capacity retention rate (%) = (discharge capacity at the 400th cycle / initial discharge capacity) x 100

[0079] The results of the high-temperature storage characteristics, gas generation amount, and cycle characteristics are shown in Tables 1 and 2 as relative values, with the result when comparative nonaqueous electrolyte 0 (Comparative Example 0) being set at 100.0. For the "80°C storage test capacity retention rate" and "25°C cycle test capacity retention rate," the larger the value, the more preferable, and for the "80°C storage test gas generation amount," the smaller the value, the more preferable.

[0080]

[0081]

[0082] The structures of the compounds listed in the above table are shown below.

[0083]

[0084] In addition, in the above table, "LiTFOP" means "lithium tetrafluorooxalatophosphate," "LiDFBOP" means "lithium difluorobis(oxalato)phosphate," "TVSF" means "trivinylfluorosilane," "TVS" means "tetravinylsilane," "LiBDFPI" means "lithium bis(difluorophosphoryl)imide," "LiDFPFSI" means "lithium (difluorophosphoryl)(fluorosulfonyl)imide," "TPP" means "tripropargyl phosphate," "LiNO3" means "lithium nitrate," "LiFS" means "lithium fluorosulfonate," and "LiDFP" means "lithium difluorophosphate."

[0085] From Tables 1 and 2, it was found that the cells containing the nonaqueous electrolytes of the examples had a large "80°C storage test capacity retention rate" and excellent high-temperature storage characteristics. Furthermore, it was found that the cells containing the nonaqueous electrolytes of the examples had a small "80°C storage test gas generation rate" and a large "25°C cycle test capacity retention rate."

[0086] According to the present disclosure, it is possible to provide a nonaqueous electrolyte, a nonaqueous electrolyte battery, and a method for manufacturing a nonaqueous electrolyte battery that exhibit good high-temperature storage characteristics.

[0087] 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. 2024-028590) filed on February 28, 2024, the contents of which are incorporated herein by reference.

Claims

1. A non-aqueous electrolyte comprising: (I) a solute; (II) a non-aqueous organic solvent; (III) tris(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite; and (IV) fluoroethylene carbonate.

2. The nonaqueous electrolyte according to claim 1, which is for a nonaqueous electrolyte battery having a negative electrode in which graphite and at least one selected from the group consisting of Si and Si metal oxides are used as negative electrode active materials.

3. The above (I) is LiPF ６ , LiBF ４ , LiSbF ６ , LiAsF ６ , LiClO ４ , LiN(FSO ２ ) ２ , LiAlO ２ , LiAlCl ４ 2. The nonaqueous electrolyte according to claim 1, wherein the nonaqueous electrolyte is at least one selected from the group consisting of LiCl, LiI, and LiI.

4. The above (I) is NaPF ６ , NaBF ４ , NaSbF ６ , NaAsF ６ , NaClO ４ , NaN(FSO ２ ) ２ , NaAlO ２ , NaAlCl ４ 2. 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.

5. The nonaqueous electrolyte according to claim 1, wherein (II) comprises at least one selected from the group consisting of cyclic esters, chain esters, cyclic ethers, chain ethers, sulfone compounds, sulfoxide compounds, and ionic liquids.

6. The non-aqueous electrolyte according to claim 5, wherein the cyclic ester comprises a cyclic carbonate.

7. The nonaqueous electrolyte according to claim 6, wherein the cyclic carbonate comprises at least one selected from the group consisting of ethylene carbonate and propylene carbonate.

8. The non-aqueous electrolyte according to claim 5, wherein the chain ester comprises a chain carbonate.

9. The nonaqueous electrolyte according to claim 8, wherein the chain carbonate comprises at least one selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, and methyl propyl carbonate.

10. The nonaqueous electrolyte according to claim 5, wherein the cyclic ether comprises at least one selected from the group consisting of tetrahydrofuran, 2-methyltetrahydrofuran, furan, tetrahydropyran, 1,3-dioxane, 1,4-dioxane, 1,3-dioxolane, and trioxane.

11. The nonaqueous electrolyte according to claim 5, wherein the chain ether comprises at least one selected from the group consisting of diethyl ether, dipropyl ether, diisopropyl ether, dibutyl ether, dimethoxymethane, trimethoxymethane, 1,2-dimethoxyethane, diethoxyethane, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and tetraethylene glycol dimethyl ether.

12. Furthermore, cyclohexylbenzene, cyclohexylfluorobenzene, biphenyl, 2-fluorobiphenyl, tert-butylbenzene, tert-amylbenzene, 2-fluorotoluene, fluorobenzene, difluoroanisole, vinylene carbonate, vinylene carbonate oligomers (number average molecular weight in terms of polystyrene of 170 to 5000), vinylethylene carbonate, divinylethylene carbonate, ethynylethylene carbonate, trans-difluoroethylene carbonate, methylpropargyl carbonate, ethylpropargyl carbonate, dipropargyl carbonate, dimethylvinylene carbonate, dimethyl dicarbonate, bis(1,1,1,3,3,3-hexafluoro-1-propyl)carbonate, bis(2,2,2-trifluoroethyl)carbonate, 1,6-diisocyanatohexane, maleic anhydride, anhydrous Organic acid anhydrides such as succinic acid, 1,4-dioxane-2,6-dione, glutaric anhydride, methanedisulfonic anhydride, 1,2-ethanedisulfonic anhydride, methanesulfonic anhydride, 2-sulfobenzoic anhydride, and 1,3-propanedisulfonic anhydride, 1,3-propanesulfonic anhydride, 1,3-propanesultone, 1,3-propenesultone, 1,4-butanesultone, 2,4-butanesultone, 1,3,2-dioxathiolane-2,2-dioxide, and 4-propyl -1,3,2-dioxathiolane-2,2-dioxide, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,3-dithiane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, methylenemethane disulfonate, dimethylenemethane disulfonate, trimethylenemethane disulfonate, methyl methanesulfonate, methanesulfonyl fluoride, ethenesulfonyl fluoride, N,N'-carbonylbis(N-methylsulfamoyl fluoride), difluoro(picolinato)borate, phenyl difluorophosphate, tripropargyl phosphate, tetrafluoro(picolinato)phosphate, (ethoxy)pentafluorocyclotriphosphazene, succinonitrile, methyldifluorovinylsilane, methylfluorodivinylsilane, dimethyldivinylsilane, trivinylmethylsilane, trivinylfluorosilane, tetravinylsilane, tris(trimethylsilyl)borate, tris(trimethylsilyl)phosphate, 1,3-dimethyl-1,3-divinyl-1,3-di(1,1,1,3,3,3-Hexafluoroisopropyl)disiloxane, fluorosulfonate, trifluoromethanesulfonate, pentafluoroethanesulfonate, nonafluorobutanesulfonate, monomethyl sulfate, monoethyl sulfate, bis(trifluoromethanesulfonyl)imide salt, bis(pentafluoroethanesulfonyl)imide salt, (trifluoromethanesulfonyl)(nonafluorobutanesulfonyl)imide salt, (trifluoromethanesulfonyl)(pentafluoroethanesulfonyl)imide salt, (trifluoromethanesulfonyl)(fluorosulfonyl)imide salt, (pentafluoroethanesulfonyl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (difluorophosphoryl)(trifluoromethanesulfonyl)imide salt, bis(difluorophosphoryl)imide salt, (fluorosulfonyl)(carbonyl) 2. The non-aqueous electrolyte solution according to claim 1, comprising at least one selected from the group consisting of (trifluoromethanesulfonyl)(lithium carbonyloxymethanesulfonate)imide salt, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, (carbonyldi(propargyl)phosphoryl)imide salt, monofluorophosphate, difluorophosphate, tetrafluoro(malonato)phosphate, tris(oxalato)phosphate, difluorobis(oxalato)phosphate, tetrafluorooxalatophosphate, bis(oxalato)borate, difluorooxalatoborate, difluoro(malonato)borate, tris(trifluoromethanesulfonyl)methide salt, tris(fluorosulfonyl)methide salt, acrylate, methacrylate, nitrate, nitrite, hexafluoroisopropanol, and trifluoroethanol.

13. The nonaqueous electrolyte solution according to claim 1, further comprising at least one selected from tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, nitrate, fluorosulfonate, and difluorophosphate.

14. The nonaqueous electrolyte solution according to claim 1, further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(lithium carbonyloxymethanesulfonate)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, fluorosulfonate, and difluorophosphate.

15. The nonaqueous electrolyte solution according to claim 1, further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, tetravinylsilane, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, and difluorophosphate.

16. The nonaqueous electrolyte solution according to claim 1, further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyloxymethanesulfonate lithium)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, fluorosulfonate, and difluorophosphate.

17. The nonaqueous electrolyte solution according to claim 1, further comprising at least one selected from the group consisting of trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salts, tripropargyl phosphate, 1,3-dithiolane-1,1,3,3-tetraoxide, 1,2-oxathiolan-5-one-2,2-dioxide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salts, and difluorophosphate salts.

18. The nonaqueous electrolyte solution according to claim 1, further comprising at least one selected from the group consisting of tetrafluorooxalatophosphate, difluorobis(oxalato)phosphate, trivinylfluorosilane, tetravinylsilane, bis(difluorophosphoryl)imide salt, (difluorophosphoryl)(fluorosulfonyl)imide salt, (fluorosulfonyl)(carbonyloxymethanesulfonate lithium)imide, (fluorosulfonyl)(carbonyldi(2-propenyl)phosphoryl)imide salt, nitrate, fluorosulfonate, and difluorophosphate.

19. The nonaqueous electrolyte solution according to claim 1, further comprising at least one selected from the group consisting of difluorobis(oxalato)phosphates, (difluorophosphoryl)(fluorosulfonyl)imide salts, (fluorosulfonyl)(carbonyloxymethanesulfonic acid lithium)imide, nitrates, and fluorosulfonates.

20. A non-aqueous electrolyte battery comprising at least a positive electrode, a negative electrode, and the non-aqueous electrolyte according to any one of claims 1 to 19.

21. A nonaqueous electrolyte battery comprising at least a positive electrode, a negative electrode having graphite and at least one material selected from the group consisting of silicon and silicon metal oxides as negative electrode active materials, and the nonaqueous electrolyte according to any one of claims 1 to 19.

22. The nonaqueous electrolyte battery of claim 20, further comprising a separator.

23. A method for producing a non-aqueous electrolyte battery, comprising the step of injecting the non-aqueous electrolyte according to any one of claims 1 to 19.

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