JP7157622B2 - Non-aqueous electrolyte and non-aqueous electrolyte battery - Google Patents

Description

The present invention relates to non-aqueous electrolyte solutions. More specifically, the present invention relates to a non-aqueous electrolytic solution that suppresses increases in internal resistance and swelling due to charging and discharging and has an excellent capacity retention rate, and a non-aqueous electrolytic solution battery using the same.

BACKGROUND ART Non-aqueous electrolyte secondary batteries such as lithium secondary batteries have been put to practical use in a wide range of applications, such as power sources for mobile phones, laptop computers, etc., vehicle power sources for driving automobiles, etc., and large stationary power sources. However, in recent years, the demand for higher performance of non-aqueous electrolyte secondary batteries has been increasing. A high standard is required.

In order to improve battery characteristics such as cycle characteristics of non-aqueous electrolyte secondary batteries, it has been previously proposed to use additives for non-aqueous electrolyte solutions. For example, Patent Literature 1 discloses a technique capable of improving cycle characteristics and the like by including a disulfide derivative in a non-aqueous electrolytic solution. Further, Patent Document 2 discloses a technique capable of improving low-temperature discharge characteristics and the like by including a siloxane derivative in a non-aqueous electrolytic solution.

JP-A-2001-52735 JP-A-2006-93064

In Patent Documents 1 and 2, the increase in internal resistance and swelling due to additives was not sufficiently studied. The present invention has been made in view of such background art, and provides a non-aqueous electrolytic solution and a non-aqueous electrolytic solution secondary battery that suppresses the increase in internal resistance and swelling due to charging and discharging while having an excellent capacity retention rate. intended to

As a result of intensive studies to solve the above problems, the present inventors have found that in a non-aqueous electrolyte used in a non-aqueous electrolyte secondary battery, the non-aqueous electrolyte is a compound having a Si—S partial structure. By including, it was found that the above problems can be solved. That is, the gist of the present invention is as follows.

（式（１）中、Ｒ^１～Ｒ^４はそれぞれ水素原子、ハロゲン原子、ハロゲン原子を有してい
てもよい炭素数１～４のアルキル基又はハロゲン原子を有していてもよい炭素数６～１０
のアリール基を表す。） [1] A non-aqueous electrolytic solution containing a non-aqueous solvent and a compound represented by the following formula (1).

(In the formula (1), each of R ¹ to R ⁴ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, or a 6 carbon atoms which may have a halogen atom. ~10
represents an aryl group of )

[2] The nonaqueous system according to [1], wherein the compound represented by formula (1) includes at least one selected from the group consisting of tetramethylorthothiosilicate, tetraethylorthothiosilicate and tetraphenylorthothiosilicate. Electrolyte.
[3] The non-aqueous electrolytic solution according to [1] or [2], wherein the content of the compound represented by the formula (1) is 0.001% by mass or more and 20% by mass or less.

[4] A non-aqueous electrolyte secondary battery comprising a negative electrode and a positive electrode capable of absorbing and releasing metal ions, and a non-aqueous electrolyte, wherein the non-aqueous electrolyte is any one of [1] to [3] A non-aqueous electrolyte secondary battery, which is the non-aqueous electrolyte according to the above item.

ADVANTAGE OF THE INVENTION According to the present invention, it is possible to provide a non-aqueous electrolytic solution capable of suppressing an increase in internal resistance due to charging and discharging while having an excellent capacity retention rate, and a non-aqueous electrolytic solution secondary battery using the same. .

The present invention will be described in detail below. The following description is an example (representative example) of the present invention, and the present invention is not limited to these. In addition, the present invention can be arbitrarily changed and implemented without departing from the gist thereof.

[Non-aqueous electrolyte]
The non-aqueous electrolytic solution of the present invention contains a non-aqueous solvent and a compound represented by the following formula (1). In addition, below, the compound represented by Formula (1) may be called "compound (1)."

(In the formula (1), each of R ¹ to R ⁴ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, or a 6 carbon atoms which may have a halogen atom. ~10
represents an aryl group of )

The non-aqueous electrolytic solution of the present invention has the effect of being able to suppress increases in internal resistance and swelling due to charging and discharging while being excellent in capacity retention rate. Although the reason why the present invention produces such effects is not clear, it is presumed to be due to the following reasons. That is, the compound represented by formula (1) forms a film derived from compound (1) on the positive electrode by reacting under a constant potential,
It is presumed that it suppresses the oxidative decomposition of the electrolytic solution. Normally, in non-aqueous electrolyte secondary batteries, the electrolyte is oxidatively decomposed by repeated charging and discharging, but this side reaction is one of the causes of deterioration such as a decrease in capacity retention rate, an increase in internal resistance, and battery swelling. there were. It is presumed that the oxidative decomposition of the electrolytic solution is suppressed by forming a good film derived from the compound (1) on the positive electrode, thereby suppressing the deterioration due to the oxidative decomposition.

<1. Compound (1)>
The non-aqueous electrolytic solution of the present invention contains the compound represented by the formula (1). In the above formula (1), each of R ¹ to R ⁴ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, or 6 carbon atoms which may have a halogen atom. ~10 aryl groups. Among these, an alkyl group having 1 to 4 carbon atoms which may have a halogen atom or an aryl group having 6 to 10 carbon atoms which may have a halogen atom is preferable, and methyl group, ethyl group, A propyl group, a butyl group, a phenyl group, or a phenyl group in which some hydrogen atoms are substituted with fluorine are particularly preferred. More specifically, among the compounds represented by the formula (1), it is preferable to include at least one selected from the group consisting of tetramethylorthothiosilicate, tetraethylorthothiosilicate and tetraphenylorthothiosilicate.

The content of the compound represented by Formula (1) in the non-aqueous electrolytic solution is not particularly limited as long as it does not significantly impair the effects of the present invention. Specifically, the lower limit of the content of this compound in the non-aqueous electrolytic solution is preferably 0.001% by mass or more, more preferably 0.05% by mass or more, and 0.1% by mass or more. % by mass or more is more preferable. The upper limit is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less in the non-aqueous electrolytic solution. When the concentration of this compound is within the above preferable range, the effect of suppressing increase in internal resistance and swelling is more likely to be exhibited without impairing other battery performances.

<2. Non-aqueous solvent>
The non-aqueous electrolytic solution of the present invention usually contains a non-aqueous solvent for dissolving the electrolyte to be treated as a main component, similarly to general non-aqueous electrolytic solutions. The non-aqueous solvent used here is not particularly limited, and known organic solvents can be used. Organic solvents are preferably saturated cyclic carbonates, chain carbonates, chain carboxylic acid esters, cyclic carboxylic acid esters,
At least one selected from ether-based compounds and sulfone-based compounds,
It is not particularly limited to these. These can be used individually by 1 type or in combination of 2 or more types.

<2-1. Saturated cyclic carbonate>
Saturated cyclic carbonates include those having an alkylene group with 2 to 4 carbon atoms. Specifically, examples of saturated cyclic carbonates having 2 to 4 carbon atoms include ethylene carbonate, propylene carbonate, and butylene carbonate. Among them, ethylene carbonate and propylene carbonate are preferable from the viewpoint of improvement in battery characteristics resulting from improvement in the degree of dissociation of lithium ions. Saturated cyclic carbonates may be used alone, or two or more of them may be used in any combination and ratio.

The content of the saturated cyclic carbonate is not particularly limited, and is arbitrary as long as it does not significantly impair the effects of the present invention. It is 3% by volume or more, preferably 5% by volume or more. By setting it in this range, it is easy to avoid a decrease in electrical conductivity due to a decrease in the dielectric constant of the non-aqueous electrolyte, and to make the large current discharge characteristics of the electricity storage device, the stability to the negative electrode, and the cycle characteristics within a good range. . The upper limit is usually 90% by volume or less, preferably 85% by volume or less, more preferably 80% by volume or less. By setting the viscosity of the non-aqueous electrolyte in this range, the viscosity of the non-aqueous electrolyte is set to an appropriate range, suppressing the decrease in ionic conductivity, further improving the input/output characteristics of the electricity storage device, and improving durability such as cycle characteristics and storage characteristics. It is preferable because it can be improved further.

<2-2. Chain carbonate>
As the chain carbonate, those having 3 to 7 carbon atoms are preferred. Specifically, carbon number 3 ~
Examples of chain carbonates of 7 include dimethyl carbonate, diethyl carbonate, di-n
- propyl carbonate, diisopropyl carbonate, n-propyl isopropyl carbonate, ethyl methyl carbonate, methyl-n-propyl carbonate, n-butyl methyl carbonate, isobutyl methyl carbonate, t-butyl methyl carbonate,
ethyl-n-propyl carbonate, n-butyl ethyl carbonate, isobutyl ethyl carbonate, t-butyl ethyl carbonate and the like. Among these, dimethyl carbonate, diethyl carbonate, di-n-propyl carbonate, diisopropyl carbonate, n-propyl isopropyl carbonate, ethyl methyl carbonate,
Methyl-n-propyl carbonate is preferred, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate being particularly preferred.

In addition, linear carbonates having a fluorine atom (hereinafter referred to as "fluorinated linear carbonate"
may be abbreviated as ) can also be suitably used. The number of fluorine atoms in the fluorinated linear carbonate is not particularly limited as long as it is 1 or more, but it is usually 6 or less, preferably 4 or less. When the fluorinated linear carbonate has a plurality of fluorine atoms, they may be bonded to the same carbon or different carbons. Examples of fluorinated chain carbonates include fluorinated dimethyl carbonate derivatives, fluorinated ethylmethyl carbonate derivatives, fluorinated diethyl carbonate derivatives and the like.

A chain carbonate may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

The content of the chain carbonate is not particularly limited, but usually 15% in 100% by volume of the non-aqueous solvent.
% by volume or more, preferably 20% by volume or more, more preferably 25% by volume or more.
Also, it is usually 90% by volume or less, preferably 85% by volume or less, more preferably 80% by volume or less. By setting the content of the chain carbonate within the above range, the viscosity of the non-aqueous electrolytic solution is set in an appropriate range, the decrease in ionic conductivity is suppressed, and the input/output characteristics and charge/discharge rate characteristics of the electricity storage device are improved. Easier to range. In addition, it becomes easy to avoid a decrease in electrical conductivity due to a decrease in the dielectric constant of the non-aqueous electrolytic solution, and to make the input/output characteristics and charge/discharge rate characteristics of the electricity storage device within favorable ranges.

<2-3. Chain carboxylic acid ester>
Chain carboxylic acid esters include those having a total carbon number of 3 to 7 in the structural formula. Specifically, methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, t-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, Isopropyl Propionate, Propionate-n
-butyl, isobutyl propionate, t-butyl propionate, methyl butyrate, ethyl butyrate, -n-propyl butyrate, isopropyl butyrate, methyl isobutyrate, ethyl isobutyrate, -n-propyl isobutyrate, isopropyl isobutyrate, and the like. be done. Among these, methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, methyl propionate, ethyl propionate, n-propyl propionate, isopropyl propionate, methyl butyrate, ethyl butyrate, etc. It is preferable from the viewpoint of improvement in ion conductivity due to the decrease and suppression of battery swelling during endurance tests such as cycling and storage.

<2-4. Cyclic carboxylic acid ester>
Cyclic carboxylic acid esters include those having 3 to 12 total carbon atoms in the structural formula. Specific examples include gamma-butyrolactone, gamma-valerolactone, gamma-caprolactone, epsilon-caprolactone and the like. Among these, gamma-butyrolactone is particularly preferable from the viewpoint of improvement in battery characteristics resulting from improvement in the degree of dissociation of lithium ions.

<2-5. Ether-based compound>
Preferred ether compounds are chain ethers having 3 to 10 carbon atoms and cyclic ethers having 3 to 6 carbon atoms.

Chain ethers having 3 to 10 carbon atoms include diethyl ether, di(2-fluoroethyl) ether, di(2,2-difluoroethyl) ether, di(2,2,2-trifluoroethyl) ether, ethyl (2-fluoroethyl) ether, ethyl (2,2,2-trifluoroethyl) ether, ethyl (1,1,2,2-tetrafluoroethyl) ether, (2-fluoroethyl) (2,2,2 -trifluoroethyl)ether, (2-fluoroethyl)(1,1,2,2-tetrafluoroethyl)ether, (2,2,2-trifluoroethyl)(1,1,2,2-tetrafluoro ethyl) ether, ethyl-n-propyl ether, ethyl (3-fluoro-n-propyl) ether, ethyl (3,3,3-
trifluoro-n-propyl) ether, ethyl (2,2,3,3-tetrafluoro-n
-propyl) ether, ethyl (2,2,3,3,3-pentafluoro-n-propyl)
ether, 2-fluoroethyl-n-propyl ether, (2-fluoroethyl) (3-
fluoro-n-propyl) ether, (2-fluoroethyl)(3,3,3-trifluoro-n-propyl) ether, (2-fluoroethyl)(2,2,3,3-tetrafluoro-n- propyl) ether, (2-fluoroethyl) (2,2,3,3,3-pentafluoro-n-propyl) ether, 2,2,2-trifluoroethyl-n-propyl ether, (2,2, 2-trifluoroethyl)(3-fluoro-n-propyl) ether,
(2,2,2-trifluoroethyl)(3,3,3-trifluoro-n-propyl) ether, (2,2,2-trifluoroethyl)(2,2,3,3-tetrafluoro- n-propyl)ether, (2,2,2-trifluoroethyl)(2,2,3,3,3-pentafluoro-n-propyl)ether, 1,1,2,2-tetrafluoroethyl-n - propyl ether, (1,1,2,2-tetrafluoroethyl)(3-fluoro-n-propyl) ether, (1,1,2,2-tetrafluoroethyl)(3,3,3-trifluoro -n-propyl)ether, (1,1,2,2-tetrafluoroethyl)(2,2,3,
3-tetrafluoro-n-propyl) ether, (1,1,2,2-tetrafluoroethyl)(2,2,3,3,3-pentafluoro-n-propyl) ether, di-n-propyl ether , (n-propyl) (3-fluoro-n-propyl) ether, (n-propyl) (3,3,3-trifluoro-n-propyl) ether, (n-propyl) (2,2
,3,3-tetrafluoro-n-propyl)ether, (n-propyl)(2,2,3,
3,3-pentafluoro-n-propyl) ether, di(3-fluoro-n-propyl)
ether, (3-fluoro-n-propyl)(3,3,3-trifluoro-n-propyl) ether, (3-fluoro-n-propyl)(2,2,3,3-tetrafluoro-n-
propyl) ether, (3-fluoro-n-propyl)(2,2,3,3,3-pentafluoro-n-propyl) ether, di(3,3,3-trifluoro-n-propyl) ether, (3,3,3-trifluoro-n-propyl)(2,2,3,3-tetrafluoro-n-propyl) ether, (3,3,3-trifluoro-n-propyl)(2,2 , 3
,3,3-pentafluoro-n-propyl) ether, di(2,2,3,3-tetrafluoro-n-propyl) ether, (2,2,3,3-tetrafluoro-n-propyl) (
2,2,3,3,3-pentafluoro-n-propyl) ether, di(2,2,3,3,
3-pentafluoro-n-propyl) ether, di-n-butyl ether, dimethoxymethane, methoxyethoxymethane, methoxy(2-fluoroethoxy)methane, methoxy (
2,2,2-trifluoroethoxy)methanemethoxy(1,1,2,2-tetrafluoroethoxy)methane, diethoxymethane, ethoxy(2-fluoroethoxy)methane, ethoxy(2,2,2-trifluoro ethoxy)methane, ethoxy(1,1,2,2-tetrafluoroethoxy)methane, di(2-fluoroethoxy)methane, (2-fluoroethoxy)(2,2,2-trifluoroethoxy)methane, (2 -fluoroethoxy) (1,1
,2,2-tetrafluoroethoxy)methane di(2,2,2-trifluoroethoxy)methane, (2,2,2-trifluoroethoxy)(1,1,2,2-tetrafluoroethoxy)methane, di (1,1,2,2-tetrafluoroethoxy)methane, dimethoxyethane, methoxyethoxyethane, methoxy(2-fluoroethoxy)ethane, methoxy(2,
2,2-trifluoroethoxy)ethane, methoxy(1,1,2,2-tetrafluoroethoxy)ethane, diethoxyethane, ethoxy(2-fluoroethoxy)ethane, ethoxy(2,2,2-trifluoroethoxy) ) ethane, ethoxy (1,1,2,2-tetrafluoroethoxy) ethane, di (2-fluoroethoxy) ethane, (2-fluoroethoxy) (2,2,2-trifluoroethoxy) ethane, (2- fluoroethoxy) (1,1,
2,2-tetrafluoroethoxy)ethane, di(2,2,2-trifluoroethoxy)ethane, (2,2,2-trifluoroethoxy)(1,1,2,2-tetrafluoroethoxy)ethane, di(1,1,2,2-tetrafluoroethoxy)ethane, ethylene glycol di-n-propyl ether, ethylene glycol di-n-butyl ether, diethylene glycol dimethyl ether and the like.

Cyclic ethers include tetrahydrofuran, 2-methyltetrahydrofuran, 3-methyltetrahydrofuran, 1,3-dioxane, 2-methyl-1,3-dioxane, 4-
Examples include methyl-1,3-dioxane, 1,4-dioxane, and fluorinated compounds thereof. Among these, dimethoxymethane, diethoxymethane, ethoxymethoxymethane, ethylene glycol di-n-propyl ether, ethylene glycol di-n-butyl ether, and diethylene glycol dimethyl ether have high solvating ability to lithium ions and dissociate lithium ions. is preferable in terms of improving Particularly preferred are dimethoxymethane, diethoxymethane, and ethoxymethoxymethane, since they have low viscosity and give high ionic conductivity.

<2-6. Sulfone compound>
Preferred sulfone compounds are cyclic sulfones having 3 to 6 carbon atoms and chain sulfones having 2 to 6 carbon atoms. The number of sulfonyl groups in one molecule is preferably one or two.

Cyclic sulfones include trimethylene sulfones, tetramethylene sulfones and hexamethylene sulfones which are monosulfone compounds; and trimethylene disulfones, tetramethylene disulfones and hexamethylene disulfones which are disulfone compounds. Among these, tetramethylenesulfones, tetramethylenedisulfones, hexamethylenesulfones, and hexamethylenedisulfones are more preferable, and tetramethylenesulfones (sulfolanes) are particularly preferable from the viewpoint of dielectric constant and viscosity.

As sulfolanes, sulfolane and/or sulfolane derivatives (hereinafter sometimes abbreviated as “sulfolane” including sulfolane) are preferable. As the sulfolane derivative, one in which one or more hydrogen atoms bonded to carbon atoms constituting a sulfolane ring is substituted with a fluorine atom or an alkyl group is preferable.

Among these, 2-methylsulfolane, 3-methylsulfolane, 2-fluorosulfolane, 3-fluorosulfolane, 2,2-difluorosulfolane, 2,3-difluorosulfolane, 2,4-difluorosulfolane, 2,5-difluorosulfolane Sulfolane, 3,4-difluorosulfolane, 2-fluoro-3-methylsulfolane, 2-fluoro-2-methylsulfolane, 3-fluoro-3-methylsulfolane, 3-fluoro-2-methylsulfolane, 4-fluoro-3 -methylsulfolane, 4-fluoro-2-methylsulfolane, 5-
fluoro-3-methylsulfolane, 5-fluoro-2-methylsulfolane, 2-fluoromethylsulfolane, 3-fluoromethylsulfolane, 2-difluoromethylsulfolane,
3-difluoromethylsulfolane, 2-trifluoromethylsulfolane, 3-trifluoromethylsulfolane, 2-fluoro-3-(trifluoromethyl)sulfolane, 3-fluoro-3-(trifluoromethyl)sulfolane, 4-fluoro- 3-(Trifluoromethyl)sulfolane, 5-fluoro-3-(trifluoromethyl)sulfolane and the like are preferable in terms of high ionic conductivity and high input/output.

Examples of chain sulfone include dimethylsulfone, ethylmethylsulfone, diethylsulfone, n-propylmethylsulfone, n-propylethylsulfone, di-n-propylsulfone, isopropylmethylsulfone, isopropylethylsulfone, diisopropylsulfone, n- butylmethylsulfone, n-butylethylsulfone, t-butylmethylsulfone, t-butylethylsulfone, monofluoromethylmethylsulfone, difluoromethylmethylsulfone, trifluoromethylmethylsulfone, monofluoroethylmethylsulfone, difluoroethylmethylsulfone, trifluoroethylmethylsulfone, pentafluoroethylmethylsulfone, ethylmonofluoromethylsulfone, ethyldifluoromethylsulfone, ethyltrifluoromethylsulfone, perfluoroethylmethylsulfone, ethyltrifluoroethylsulfone, ethylpentafluoroethylsulfone, di(tri fluoroethyl)sulfone, perfluorodiethylsulfone, fluoromethyl-n-propylsulfone, difluoromethyl-n-propylsulfone, trifluoromethyl-n-
Propylsulfone, Fluoromethylisopropylsulfone, Difluoromethylisopropylsulfone, Trifluoromethylisopropylsulfone, Trifluoroethyl-n-propylsulfone, Trifluoroethylisopropylsulfone, Pentafluoroethyl-n-
Propyl sulfone, pentafluoroethyl isopropyl sulfone, trifluoroethyl-
Examples include n-butylsulfone, trifluoroethyl-t-butylsulfone, pentafluoroethyl-n-butylsulfone, pentafluoroethyl-t-butylsulfone and the like.

Among these, dimethylsulfone, ethylmethylsulfone, diethylsulfone, n-
propylmethylsulfone, isopropylmethylsulfone, n-butylmethylsulfone, t
- butylmethylsulfone, monofluoromethylmethylsulfone, difluoromethylmethylsulfone, trifluoromethylmethylsulfone, monofluoroethylmethylsulfone, difluoroethylmethylsulfone, trifluoroethylmethylsulfone, pentafluoroethylmethylsulfone, ethylmonofluoromethylsulfone , ethyldifluoromethylsulfone, ethyltrifluoromethylsulfone, ethyltrifluoroethylsulfone, ethylpentafluoroethylsulfone, trifluoromethyl-n-propylsulfone, trifluoromethylisopropylsulfone, trifluoroethyl-n-butylsulfone, trifluoro Ethyl-t-butylsulfone, trifluoromethyl-n-butylsulfone, trifluoromethyl-t-butylsulfone and the like are preferable in terms of high ionic conductivity and high input/output.

<3. Electrolyte>
The non-aqueous electrolytic solution of the present invention usually contains an electrolyte. In particular, when the non-aqueous electrolyte of the present invention is a lithium ion secondary battery, it usually contains a lithium salt.

Examples of lithium salts that can be used in the non-aqueous electrolytic solution of the present invention include LiClO
₄ , _LiBF4 , _LiPF6 , _LiAsF6 , _LiTaF6 , _{LiCF3SO3 ,} LiC
_4F9SO3 , Li _{( FSO2} ) _2N , _{Li ( CF3SO2} ) _2N , Li _{( C2F5SO
2} ) 2N, Li _{( CF3} )SO2) _3C , _{LiBF3 ( C2F5} ), _{LiB ( C2O4} )
₂ , LiB( _C6F5 ) _{4 , LiPF3(C2F5)3 , and the like} . Of these,
Preferred _{are LiPF6} , _LiBF4 , LiClO4, Li _{( FSO2} )2N and L
at least one selected from i(CF ₃ SO ₂ ) ₂ N, more preferably LiP
At least one selected from F ₆ , LiBF ₄ , Li(FSO ₂ ) ₂ N and Li(CF ₃ SO ₂ ) ₂ N, more preferably LiPF ₆ and Li(CF ₃ SO ₂ ) ₂ N LiPF 6 is at least one of them, and LiPF ₆ is particularly preferred. The lithium salts listed above may be used alone, or two or more of them may be used in combination.

The concentration of the electrolyte such as a lithium salt in the final composition of the non-aqueous electrolytic solution of the present invention is arbitrary as long as it does not significantly impair the effects of the present invention, but is preferably 0.5 mol / L or more, more preferably. is 0.6 mol/L or more, more preferably 0.7 mol/L or more, while preferably 3 mol/L or less, more preferably 2 mol/L or less, still more preferably 1.8 mol/L L or less. When the content of the lithium salt is within the above range, the ionic conductivity can be appropriately increased.

The method for measuring the content of the lithium salt mentioned above is not particularly limited, and any known method can be used. Such methods include, for example, ion chromatography, F magnetic resonance spectroscopy, and the like.

<4. Other Additives>
The non-aqueous electrolytic solution of the present invention contains, in addition to the various compounds listed above, cyano groups such as malononitrile, succinonitrile, glutaronitrile, adiponitrile, pimelonitrile, suberonitrile, azelanitrile, sebaconitrile, undecanedinitrile, and dodecanedinitrile. 1,3-bis(isocyanatomethyl)cyclohexane, 1,4-bis(
isocyanatomethyl)cyclohexane, 1,3-phenylene diisocyanate, 1,4-
phenylene diisocyanate, 1,2-bis(isocyanatomethyl)benzene, 1,3-
isocyanato compounds such as bis(isocyanatomethyl)benzene, 1,4-bis(isocyanatomethyl)benzene, acrylic anhydride, 2-methylacrylic anhydride, 3-methylacrylic anhydride, benzoic anhydride, 2-methylbenzoic anhydride, 4-methylbenzoic anhydride, 4-tert-butylbenzoic anhydride, 4-fluorobenzoic anhydride, 2,3,4,
Carboxylic acid anhydride compounds such as 5,6-pentafluorobenzoic anhydride, methoxyformic anhydride, ethoxyformic anhydride, succinic anhydride and maleic anhydride, and cyclic unsaturated bonds such as vinylene carbonate and vinylethylene carbonate Carbonates, sulfonic acid ester compounds such as 1,3-propanesultone, phosphates such as lithium difluorophosphate, sulfonates such as lithium fluorosulfonate, and the like may be added. However, although lithium difluorophosphate and lithium fluorosulfonate mentioned here correspond to lithium salts, they are not treated as electrolytes from the viewpoint of the degree of ionization with respect to non-aqueous solvents used in non-aqueous electrolytes, and are not treated as additives. shall be positioned as Various additives such as cyclohexylbenzene, t-butylbenzene, t-amylbenzene, biphenyl, alkylbiphenyl, terphenyl, partially hydrogenated terphenyl, diphenyl ether, and dibenzofuran are added as overcharge inhibitors. can be blended within a range that does not significantly impair the These compounds may be used in combination as appropriate. Among these, from the viewpoint of capacity retention rate,
Vinylene carbonate, lithium difluorophosphate, and lithium fluorosulfonate are particularly preferred, and a combination of these is particularly preferred.

[Non-aqueous electrolyte battery]
A non-aqueous electrolyte battery (hereinafter sometimes referred to as "non-aqueous electrolyte battery of the present invention") can be made by using the non-aqueous electrolyte, positive electrode and negative electrode of the present invention. Non-aqueous electrolyte batteries include, for example, lithium ion secondary batteries, sodium ion secondary batteries and the like, and lithium ion secondary batteries are preferred. Lithium ion secondary batteries usually have the non-aqueous electrolyte solution of the present invention, a current collector, and a positive electrode active material layer provided on the current collector, and are composed of a positive electrode capable of intercalating and deintercalating lithium ions, and a collector. It comprises a current collector and a negative electrode having a negative electrode active material layer provided on the current collector and capable of intercalating and deintercalating lithium ions.

<1. Positive electrode>
Examples of positive electrode materials that serve as active materials for the positive electrode of the non-aqueous secondary battery of the present invention include lithium cobalt composite oxides whose basic composition is represented by LiCoO ₂ , lithium nickel composite oxides whose basic composition is represented by LiNiO ₂ , and LiMnO. ₂ and lithium-manganese composite oxides represented by LiMn ₂ O ₄ , transition metal oxides such as manganese dioxide, and mixtures of these composite oxides. Furthermore, TiS ₂ , FeS ₂ , Nb ₃ S ₄ , M
_{o3S4 , CoS2 , V2O5 , CrO3 ,} V3O3, _FeO2 , _GeO2 and Li(N
i _{1/3 Mn 1/3 Co 1/3} )O _{2 , LiFePO 4} or the like may be used. _{Ni0.5Mn0.2C _
o0.3} )O2 _, Li( _{Ni0.6Mn0.2Co0.2} ) _{O2 ,} Li _{( Ni0.8Mn
0.1Co0.1} ) _{O2 ,} Li( _{Ni0.8Co0.15Al0.05 ) O2} and the like _are particularly preferred.

<2. negative electrode>
A negative electrode generally has a negative electrode active material layer on a current collector, and the negative electrode active material layer contains a negative electrode active material. The negative electrode active material will be described below.

As the negative electrode active material, any material that can electrochemically occlude and release s-block metal ions such as lithium ions, lithium ions, potassium ions, and magnesium ions,
There are no particular restrictions. Specific examples thereof include carbonaceous materials, metal compound materials, and their oxides, carbides, nitrides, silicides, sulfides and phosphides. These may be used singly or in combination of two or more.

The carbonaceous material used as the negative electrode active material is not particularly limited, but examples thereof include graphite, amorphous carbon, and carbonaceous substances having a low degree of graphitization. Types of graphite include natural graphite and artificial graphite. Moreover, those coated with a carbonaceous material such as amorphous carbon or graphitized material may be used. Examples of amorphous carbon include particles obtained by calcining bulk mesophase and particles obtained by subjecting a carbon precursor to infusibility treatment and calcining it. Carbonaceous particles having a low degree of graphitization include those obtained by firing an organic material at a temperature of generally less than 2500°C. These may be used singly or in combination of two or more.

The metal compound-based material used as the negative electrode active material is not particularly limited, but examples include Ag, Al, Bi, Cu, Ga, Ge, In, Ni, P, Pb, Sb, Si, Sn, S
Examples include compounds containing metals such as r and Zn. Among these, silicon and/or tin elements, alloys, oxides, carbides, nitrides, etc. are preferable, and in particular, elemental Si and SiOx (
0.5≦O≦1.6) is preferable from the viewpoint of capacity per unit mass and environmental load.

<3. Separator>
A separator is usually interposed between the positive electrode and the negative electrode in order to prevent a short circuit. In this case, the non-aqueous electrolytic solution of the present invention is usually used by impregnating this separator.

There are no particular restrictions on the material and shape of the separator, and known materials can be arbitrarily adopted as long as they do not significantly impair the effects of the present invention. Among these, resins, glass fibers, inorganic substances, etc., which are formed of materials that are stable to the non-aqueous electrolytic solution of the present invention, are used, and porous sheets or non-woven fabrics having excellent liquid retention properties are used. preferably used.

As materials for the resin and glass fiber separators, for example, polyolefins such as polyethylene and polypropylene, polytetrafluoroethylene, polyethersulfone, glass filters, and the like can be used. Among these, glass filters and polyolefins are preferred, and polyolefins are more preferred. One of these materials may be used alone, or two or more of them may be used in any combination and ratio.

Although the thickness of the separator is arbitrary, it is usually 1 μm or more, preferably 5 μm or more, more preferably 10 μm or more, and usually 50 μm or less, preferably 40 μm or less, and more preferably 30 μm or less. If the separator is thinner than the above range, the insulating properties and mechanical strength may deteriorate. On the other hand, if the thickness is more than the above range, not only the battery performance such as rate characteristics may deteriorate, but also the energy density of the electricity storage device as a whole may deteriorate.

Furthermore, when a porous material such as a porous sheet or non-woven fabric is used as the separator, the porosity of the separator is arbitrary, but is usually 20% or more, preferably 35% or more, and 45%.
The above is more preferable, and it is usually 90% or less, preferably 85% or less, and more preferably 75% or less. If the porosity is too smaller than the above range, the film resistance tends to increase and the rate characteristics tend to deteriorate. On the other hand, when the thickness is too much larger than the above range, the mechanical strength of the separator tends to decrease and the insulation tends to decrease.

In addition, although the average pore size of the separator is also arbitrary, it is usually 0.5 μm or less, and 0.2 μm
The following is preferable, and it is usually 0.05 μm or more. If the average pore diameter exceeds the above range, short circuits tend to occur. On the other hand, below the above range, the film resistance may increase and the rate characteristics may deteriorate.

On the other hand, as inorganic materials, for example, oxides such as alumina and silicon dioxide, nitrides such as aluminum nitride and silicon nitride, and sulfates such as barium sulfate and calcium sulfate are used. things are used.

As for the form, thin films such as non-woven fabrics, woven fabrics and microporous films are used. In the form of a thin film, one having a pore size of 0.01 to 1 μm and a thickness of 5 to 50 μm is preferably used.
In addition to the independent thin film shape, a separator can be used in which a composite porous layer containing the inorganic particles is formed on the surface of the positive electrode and/or the negative electrode using a resin binder. For example, a porous layer may be formed on both surfaces of the positive electrode using alumina particles having a 90% particle size of less than 1 μm and a fluororesin as a binder.

<4. Conductive material>
The positive and negative electrodes described above may contain a conductive material to improve conductivity. Any known conductive material can be used as the conductive material. Specific examples include metal materials such as copper and nickel; graphite such as natural graphite and artificial graphite; carbon black such as acetylene black; and carbonaceous materials such as amorphous carbon such as needle coke. In addition, these may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

The conductive material is usually 0.01 parts by mass or more, preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, and usually 50 parts by mass or less with respect to 100 parts by mass of the positive electrode material or the negative electrode material.
It is used in an amount of preferably 30 parts by mass or less, more preferably 15 parts by mass or less.
If the content is less than the above range, the electrical conductivity may become insufficient. Moreover, when it exceeds the said range, battery capacity may fall.

<5. Binder>
The positive and negative electrodes described above may contain a binder to improve binding. The binder is
The material is not particularly limited as long as it is stable with respect to the non-aqueous electrolytic solution and the solvent used for electrode production.

In the case of the coating method, any material that dissolves or disperses in the liquid medium used during electrode production may be used. Specific examples include polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, aromatic polyamide, cellulose, nitro Resin-based polymers such as cellulose; rubbery polymers such as SBR (styrene-butadiene rubber), NBR (acrylonitrile-butadiene rubber), fluororubber, isoprene rubber, butadiene rubber, ethylene-propylene rubber; styrene-butadiene-styrene block Copolymer or hydrogenated product thereof, EPDM (ethylene-propylene-diene terpolymer), styrene-ethylene-
Thermoplastic elastomeric polymers such as butadiene/ethylene copolymers, styrene/isoprene/styrene block copolymers or hydrogenated products thereof; syndiotactic-1,2-polybutadiene, polyvinyl acetate, ethylene/vinyl acetate copolymers Soft resinous polymer such as coalescence, propylene/α-olefin copolymer; Molecules; polymer compositions having ionic conductivity of alkali metal ions (especially lithium ions). In addition, these substances may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

The ratio of the binder is usually 0.1 parts by mass or more, preferably 1 part by mass or more, more preferably 3 parts by mass or more, and usually 50 parts by mass, with respect to 100 parts by mass of the positive electrode material or the negative electrode material. 30 parts by mass or less is preferable, 10 parts by mass or less is more preferable, and 8 parts by mass or less is even more preferable. When the ratio of the binder is within the above range, the binding property of the electrode can be sufficiently maintained and the mechanical strength of the electrode can be maintained, which is preferable from the viewpoint of cycle characteristics, battery capacity and conductivity.

<6. Liquid medium>
As the liquid medium for forming the slurry, any solvent capable of dissolving or dispersing the active material, the conductive material, the binder, and the thickening agent used as necessary can be used. There is no limitation, and either an aqueous solvent or an organic solvent may be used.

Examples of the aqueous medium include water, a mixed medium of alcohol and water, and the like. Examples of organic media include aliphatic hydrocarbons such as hexane; benzene, toluene, xylene,
Aromatic hydrocarbons such as methylnaphthalene; Heterocyclic compounds such as quinoline and pyridine; Ketones such as acetone, methyl ethyl ketone and cyclohexanone; Esters such as methyl acetate and methyl acrylate; amines such as; ethers such as diethyl ether and tetrahydrofuran (THF); amides such as N-methylpyrrolidone (NMP), dimethylformamide and dimethylacetamide;
Aprotic polar solvents such as hexamethylphosphaamide and dimethylsulfoxide can be used. In addition, these may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

<7. Thickener>
When an aqueous medium is used as the liquid medium for forming the slurry, it is preferable to use a thickener and a latex such as styrene-butadiene rubber (SBR) to form the slurry. Thickeners are commonly used to adjust the viscosity of slurries.

The thickening agent is not particularly limited as long as it does not significantly limit the effects of the present invention. Specific examples include carboxymethylcellulose, methylcellulose, hydroxymethylcellulose, ethylcellulose, polyvinyl alcohol, oxidized starch, phosphorylated starch, casein and salts thereof. etc. These may be used individually by 1 type, or may use 2 or more types together by arbitrary combinations and ratios.

Furthermore, when a thickener is used, it is usually 0.1 parts by mass or more, preferably 0.5 parts by mass or more, more preferably 0.6 parts by mass or more with respect to 100 parts by mass of the positive electrode material or the negative electrode material, Also, it is usually 5 parts by mass or less, preferably 3 parts by mass or less, and more preferably 2 parts by mass or less. If it is less than the above range, the applicability may be significantly reduced, and if it exceeds the above range,
As the proportion of the active material in the active material layer decreases, the battery capacity may decrease and the resistance between the active materials may increase.

<8. Current collector>
The material of the current collector is not particularly limited, and any known material can be used. Specific examples include metal materials such as aluminum, stainless steel, nickel plating, titanium, tantalum, and copper; and carbonaceous materials such as carbon cloth and carbon paper. Among these, metal materials, particularly aluminum, are preferred.

Examples of the shape of the current collector include metal foil, metal cylinder, metal coil, metal plate, metal thin film, expanded metal, punch metal, foam metal, etc., in the case of metal materials, and carbon plate, A carbon thin film, a carbon cylinder, etc. are mentioned. Among these, metal thin films are preferred.
Incidentally, the thin film may be appropriately formed in a mesh shape.

Although the thickness of the current collector is arbitrary, it is usually 1 μm or more, preferably 3 μm or more, and 5 μm or more.
More preferably, it is usually 1 mm or less, preferably 100 μm or less, and 50 μm or less.
m or less is more preferable. When the thin film is within the above range, the strength required as a current collector is maintained,
It is also preferable from the point of handleability.

<9. Battery design>
[Electrode group]
The electrode group has a laminate structure in which the positive electrode plate and the negative electrode plate are interposed with the separator.
and a structure in which the positive electrode plate and the negative electrode plate are spirally wound with the separator interposed therebetween. The ratio of the volume of the electrode group to the internal volume of the battery (hereinafter referred to as the electrode group occupancy) is usually 40% or more, preferably 50% or more, and usually 90% or less, and 80% or less. preferable. If the electrode group occupancy is below the above range, the battery capacity will be small. If the above range is exceeded, the void space is small, and the internal pressure rises due to the swelling of the members due to the high temperature of the battery and the increase in the vapor pressure of the liquid component of the electrolyte, and the repeated charging and discharging performance as a battery. In addition, the gas release valve that releases the internal pressure to the outside may operate.

[Current collection structure]
The current collection structure is not particularly limited, but in order to more effectively improve the discharge characteristics of the non-aqueous electrolytic solution of the present invention, a structure that reduces the resistance of the wiring part and the joint part can be used. preferable. When the internal resistance is reduced in this way, the effect of using the non-aqueous electrolytic solution of the present invention is exhibited particularly well.

When the electrode group has the above-described laminated structure, a structure in which the metal core portions of the electrode layers are bundled and welded to a terminal is preferably used. When the area of one electrode increases, the internal resistance increases. Therefore, it is preferable to reduce the resistance by providing a plurality of terminals within the electrode. When the electrode group has the wound structure described above, the internal resistance can be reduced by providing a plurality of lead structures for each of the positive electrode and the negative electrode and bundling them around the terminal.

[Outer case]
The material of the exterior case is not particularly limited as long as it is stable with respect to the non-aqueous electrolytic solution used. Specifically, metals such as nickel-plated steel sheets, stainless steel, aluminum or aluminum alloys, magnesium alloys, or laminated films of resin and aluminum foil (
laminate film) is used. From the viewpoint of weight reduction, aluminum or aluminum alloy metals and laminated films are preferably used.

In the exterior case using the metals, the metals are welded together by laser welding, resistance welding, or ultrasonic welding to form a sealed structure, or the metals are crimped through a resin gasket. There are things to do. Examples of the exterior case using the laminate film include those having a sealing and airtight structure by heat-sealing the resin layers to each other.
A resin different from the resin used for the laminate film may be interposed between the resin layers in order to improve the sealing property. In particular, when the resin layer is heat-sealed through the current collector terminal to form a closed structure, the metal and the resin are joined together. A resin is preferably used.

[Protection element]
As the protective element mentioned above, the PTC (Po
active temperature coefficient), thermal fuses, thermistors, and valves (current cut-off valves) that cut off the current flowing through the circuit due to a sudden increase in the internal pressure or temperature of the battery during abnormal heat generation. It is preferable to select the protective element under conditions that do not operate under normal high-current use, and from the viewpoint of high output, it is more preferable to design the protective element so that abnormal heat generation and thermal runaway do not occur even without the protective element.

[Exterior body]
The electricity storage device of the present invention is generally configured by housing the non-aqueous electrolytic solution, the negative electrode, the positive electrode, the separator, and the like in an exterior body. There is no restriction on this exterior body, and any known one can be employed as long as it does not significantly impair the effects of the present invention.

Specifically, although the material of the exterior body is arbitrary, nickel-plated iron, stainless steel, aluminum or alloys thereof, nickel, titanium, or the like is usually used.

Also, the shape of the exterior body is arbitrary, and may be, for example, cylindrical, square, laminated, coin-shaped, large-sized, or the like.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples and reference examples, but the present invention is not limited to these examples as long as the gist thereof is not exceeded.

(Example 1)
[Preparation of negative electrode]
To 98 parts by mass of the carbonaceous material, add an aqueous dispersion of 1 part by mass of sodium carboxymethylcellulose as a thickener and binder, and add an aqueous dispersion of 1 part by mass of styrene-butadiene rubber. , and mixed with a disperser to form a slurry. The resulting slurry was applied to a copper foil with a thickness of 10 μm, dried, and rolled with a press to obtain an active material layer with a size of 32 mm in width, 42 mm in length, and 5 mm in width.
, and a shape having an uncoated portion with a length of 9 mm was cut out to obtain a negative electrode.

[Preparation of positive electrode]
Li(Ni _1/3 Mn _1/3 Co _1/3 )O ₂ 85 parts by mass as a positive electrode active material, 10 parts by mass of carbon black as a conductive material, polyvinylidene fluoride (PVd
F) and 5 parts by mass were mixed in an N-methylpyrrolidone solvent to form a slurry. The resulting slurry was applied to one side of an aluminum foil having a thickness of 15 μm, dried, and roll-pressed with a pressing machine to form active material layers with a width of 30 mm, a length of 40 mm, and a width of 5 mm and a length of 5 mm. A positive electrode was obtained by cutting out a shape having an uncoated portion with a thickness of 9 mm.

[Preparation of electrolytic solution]
Under a dry argon atmosphere, ethylene carbonate (EC) and dimethyl carbonate (DM
Dried LiPF ₆ was dissolved in a mixture of C) and ethyl methyl carbonate (EMC) (volume ratio 30:30:40) at a ratio of 1 mol/L to prepare an electrolytic solution, which was used as a basic electrolytic solution. . This basic electrolyte was mixed with tetraethyl orthothiosilicate to a concentration of 0.5% by mass, and the resulting saturated solution was used as the electrolyte of Example 1.

[Manufacture of lithium secondary battery]
A battery element was produced by stacking the positive electrode, the negative electrode, and the separator made of polypropylene in the order of the negative electrode, the separator, and the positive electrode. After inserting this battery element into a bag made of a laminated film in which both sides of aluminum (thickness 40 μm) are coated with a resin layer while projecting the positive and negative terminals, the electrolytic solution was injected into the bag and vacuumed. After sealing, a sheet-like battery of Example 1 that was fully charged at 4.2V was produced.

[Evaluation of cycle characteristics]
Voltage range 4.2V to 2.5V at 25°C for fresh batteries that have not been cycled
V, current value 1/6C
Let C. Same below. ), then charge to 4.1 V and charge for 12 hours at 60 ° C.
A time heat treatment was performed to stabilize the battery. After that, the voltage range is 4.2 V to 2.5 at 25 ° C.
The battery was charged and discharged once at V and a current value of 1/6 C, and this discharge capacity was taken as the initial discharge capacity. after that,
Charging and discharging at a voltage range of 4.2 V to 2.5 V and a current value of 1 C at 60° C. were repeated 100 times. After that, the battery was charged and discharged once at 25° C. at a voltage range of 4.2 V to 2.5 V and a current value of 1/6 C, and the discharge capacity was defined as the discharge capacity after 100 cycles. [(discharge capacity after 100 cycles) / (
initial discharge capacity)]×100 to obtain the cycle capacity retention rate (%). Table 1 shows the results.

[Evaluation of −30° C. resistance characteristics after cycle]
Before and after the 100-cycle charge-discharge test, the battery was charged at 25° C. with a constant current of 1/6 C to half the initial discharge capacity. This is 0.25 each at -30 ° C.
The battery was discharged at C, 0.5C, 0.75C, 1.0C, 1.5C and 2C, and the voltage was measured for 2 seconds. The resistance value (Ω) was obtained from the slope of the current-voltage straight line, and the internal resistance increase ratio was obtained from [(resistance value after 100 cycle test)/(resistance value before 100 cycle test)]. Table 1 shows the results.

[Evaluation of post-cycle volume change]
Before and after the 100-cycle charge/discharge test, the battery was submerged in ethanol and its mass was observed, and the buoyancy was obtained from the difference from the actual mass. The volume increase rate was obtained from [(volume after 100 cycle test)/(volume before 100 cycle test)]. Table 1 shows the results.

(Comparative example 1)
An electrolytic solution was prepared in the same manner as in Example 1, except that tetraethylorthothiosilicate was not used, and a sheet-like lithium secondary battery was produced and evaluated. Table 1 shows the results.

As is clear from Table 1 above, the lithium secondary battery using the non-aqueous electrolytic solution to which the compound (1) of the present invention is added has a high capacity retention rate, a low resistance value increase ratio, and a volume increase ratio. is low. Although the cycle test period in each of the examples and comparative examples shown in Table 1 above is modeled as a relatively short period, a significant difference is confirmed. Since the actual use of the non-aqueous electrolyte secondary battery may last several years, it can be understood that the difference in these results becomes even more significant when long-term use is assumed.

The non-aqueous electrolyte solution of the present invention can provide a non-aqueous secondary battery that suppresses increases in internal resistance and swelling due to charging and discharging and that has an excellent capacity retention rate. Therefore, the non-aqueous electrolytic solution of the present invention and the non-aqueous secondary battery obtained using the same can be used for various known applications. Specific examples include notebook computers, pen-input computers, mobile computers, e-book players, mobile phones, mobile faxes, mobile copiers, mobile printers, headphone stereos, video movies, liquid crystal televisions, handy cleaners, portable CDs, and minidiscs. , walkie-talkies, electronic notebooks, calculators, memory cards, portable tape recorders, radios, backup power sources, motors, automobiles, motorcycles, motorized bicycles, bicycles, lighting fixtures, toys, game devices, clocks, power tools, strobes, cameras, homes commercial backup power supply, office backup power supply, load leveling power supply, natural energy storage power supply, lithium ion capacitor, and the like.

Claims (4)

A non-aqueous electrolytic solution containing a non-aqueous solvent and a compound represented by the following formula (1).

(In Formula (1), R ¹ to R ⁴ are each a hydrogen atom , an alkyl group having 1 to 4 carbon atoms which may have a halogen atom, or an alkyl group having 6 to 10 carbon atoms which may have a halogen atom. represents the aryl group of.) 2. The nonaqueous electrolytic solution according to claim 1, wherein the compound represented by formula (1) includes at least one selected from the group consisting of tetramethylorthothiosilicate, tetraethylorthothiosilicate and tetraphenylorthothiosilicate. The non-aqueous electrolytic solution according to claim 1 or 2, wherein the content of the compound represented by formula (1) is 0.001% by mass or more and 20% by mass or less. A non-aqueous electrolyte secondary battery comprising a negative electrode and a positive electrode capable of absorbing and releasing metal ions, and a non-aqueous electrolyte, wherein the non-aqueous electrolyte is the non-aqueous electrolyte according to any one of claims 1 to 3. A non-aqueous electrolyte secondary battery that is an aqueous electrolyte.