JP2017117684A - Electrolytic solution for nonaqueous electrolyte battery, and nonaqueous electrolyte battery using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: an electrolytic solution for a nonaqueous electrolyte battery, which includes a novel compound and shows high-temperature cycle characteristics equivalent to those in a case in which methylene methane disulfonate is added thereto; and a nonaqueous electrolyte battery using the electrolytic solution.SOLUTION: Provided are an electrolytic solution for a nonaqueous electrolyte battery and a nonaqueous electrolyte battery using the electrolytic solution. The electrolytic solution comprises (I) a nonaqueous organic solvent, (II) a solute which is an ionic salt, and (III) a cyclic sulfonic acid anhydride derivative having an ethylene skeleton given by formula (1) and including two sulfonyl groups. The cyclic sulfonic acid anhydride derivative is arranged by using, as a raw material, a sulfur trioxide and a compound including a double bond. The content of a sulfur dioxide which is an impurity resulting from the reaction of the sulfur trioxide and the compound including a double bond is 2.5 mass% or less. (The double bond is formed between Cand R, Cand Ror Cand C.)SELECTED DRAWING: Figure 1

Description

  The present invention relates to a non-aqueous electrolyte for a non-aqueous electrolyte battery and a non-aqueous electrolyte battery using the same.

  In recent years, in batteries that are electrochemical devices, information-related equipment and communication equipment, that is, personal computers, video cameras, digital cameras, mobile phones, smartphones, and other small-sized, high-energy-density power storage systems, electric vehicles, and hybrid vehicles In addition, large-scale power storage systems such as fuel cell vehicle auxiliary power supplies and power storage are attracting attention. One of the candidates is a non-aqueous electrolyte secondary battery such as a lithium ion battery that has a high energy density and voltage and can obtain a high capacity, and is currently actively researched and developed.

As a non-aqueous electrolyte battery electrolyte (hereinafter sometimes referred to as “non-aqueous electrolyte”), a fluorine-containing electrolyte such as LiPF ₆ is dissolved as a solute in a solvent such as cyclic carbonate, chain carbonate, or ester. The non-aqueous electrolyte is often used because it is suitable for obtaining a battery having a high voltage and a high capacity. However, a non-aqueous electrolyte battery using such a non-aqueous electrolyte is not always satisfactory in terms of battery characteristics including cycle characteristics and output characteristics.

  For example, in the case of a lithium ion battery, when a lithium cation is inserted into the negative electrode during the initial charge, the negative electrode and the lithium cation, or the negative electrode and the electrolyte solvent react, and lithium oxide, lithium carbonate, or lithium alkyl carbonate is present on the negative electrode surface. A film having a main component is formed. This film on the electrode surface is called Solid Electrolyte Interface (SEI), and its properties greatly affect the battery performance, such as suppressing the reductive decomposition of the solvent and suppressing the deterioration of the battery performance and the amount of gas generation inside the battery. . Similarly, it is known that a film made of an oxidative decomposition product is formed on the surface of the positive electrode, and this also plays an important role in, for example, suppressing battery performance deterioration and gas generation inside the battery.

  Therefore, in order to improve battery characteristics such as cycle characteristics and storage characteristics, it is important to form stable SEI with high lithium ion conductivity and low electron conductivity. Attempts have been widely made to positively form good SEI by adding a small amount of the compound referred to in the electrolyte (usually 0.01% by mass or more and 10% by mass or less).

  For example, in Non-Patent Document 1 (Section 1380 2.2. Reduction-Type additive), vinylene carbonate, vinyl ethylene carbonate, vinyl acetate, maleic anhydride, vinyl pyridine and the like are electrochemically reduced and decomposed before the solvent. It is described that the decomposition product forms stable SEI on the negative electrode without dissolving in the solvent.

  In Patent Document 1, the cyclic sulfonic acid ester having two sulfonyl groups in the 19th paragraph is involved in the formation of a passive film at the electrode interface of the battery, resulting in suppression of decomposition of the solvent or positive electrode component. It is also disclosed that there is a useful effect in suppressing manganese elution. Here, in Patent Document 1, methylenemethane disulfonate (hereinafter referred to as MMDS) is particularly useful as a cyclic sulfonic acid ester having two sulfonyl groups. As shown in FIG. 3, it was a big problem that the yield during production was 40 to 51 mol% and the productivity was not high.

  Specific examples of the cyclic sulfonic acid ester having two sulfonyl groups are disclosed in Table 1 of Patent Document 1. Among them, Compound No. 21 in Table 1 is an isomer of MMDS, and is a compound called carbyl sulfate (hereinafter referred to as CS) having the same six-membered ring as a basic skeleton but also having a structure as a sulfonic anhydride. . This CS can be quantitatively produced with inexpensive raw materials such as ethylene and sulfur trioxide, as shown in the experimental section (Carbyl Sulfate) of Non-Patent Document 2.

Japanese Patent No. 4033074 International Publication No. 2012/026266 Pamphlet Japanese Patent No. 5318420 Japanese Patent No. 477964 Japanese Patent No. 5630048 Japanese Patent No. 3907446 Japanese Patent No. 5277550 Japanese Patent No. 4198992

Journal of Power Sources "A review of electritives for lithiumu-ion batteries" by Sheng Shui Zhang (2006), 162, P1379-1394. Journal of the American Chemical Society "The Synthesis of Sodium Ethylsulfonate from Ethylene" David S. Breslow, Robert R.M. Hough (1957), 79, P5000-5002. Chemistry - A European Journal "Tris (oxalato) phosphorus Acid and Its Lithium Salt" Ulrich Wietelmann, Werner Bonrath, Thomas Netscher, Heinrich Noth, Jan-Christoph Panitz and Margret Wohlfahrt-Mehrens al (2004), 10, P2451-2458

However, even when this industrially advantageous CS was synthesized and purified according to Non-Patent Document 2 and used as an additive, the high-temperature cycle characteristics at 60 ° C. were not sufficient as compared with the case where MMDS was added.
Therefore, the present invention provides a non-aqueous electrolysis comprising a cyclic sulfonic anhydride derivative having two sulfonyl groups and having an ethylene skeleton including CS, which exhibits the same high-temperature cycle characteristics at 60 ° C. as when MMDS is added. An object of the present invention is to provide a liquid battery electrolyte and a nonaqueous electrolyte battery using the same.

As a result of intensive studies by the present inventors, a cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups, produced by a conventional method of reacting sulfur trioxide with a compound containing a double bond Was found to contain about 3 to 5% by mass of sulfur dioxide, and this sulfur dioxide had an adverse effect on the high-temperature cycle characteristics.
When a high-purity, cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups with a reduced content of sulfur dioxide is used as an additive, high temperature cycle characteristics equivalent to MMDS are exhibited. As a result, they have reached the present invention.

  As a result of synthesizing CS using the method reported in the experimental section (Carbyl Sulfate) of Non-Patent Document 2, a colorless solid target product having a purity of 96.2% was obtained. When this was used as an additive for a non-aqueous electrolyte solution, the deterioration was very rapid in comparison with its isomer MMDS in a high-temperature cycle test, and the capacity was reduced by half and the battery itself was not realized. As a result of analysis, it was found that most of the impurities contained in CS are sulfur dioxide. In order to reduce the sulfur dioxide contained in this CS, for example, the CS obtained by the reaction is put in a glass container and the internal temperature is heated to 80 ° C., then nitrogen gas having a dew point of −75 ° C. is introduced for 5 hours. As a result, the sulfur dioxide content was 0.2% by mass. And when this was used as an additive for non-aqueous electrolytes, it discovered that a high temperature cycling characteristic improved significantly. In addition, regarding cyclic sulfonic anhydride derivatives having an ethylene skeleton other than CS and having two sulfonyl groups, by reducing the sulfur dioxide contained in the production process, the high temperature cycle characteristics are the same as in the case of CS. Significant improvement was confirmed.

On the other hand, sulfur dioxide is a useful additive in the electrolyte solvent containing asymmetric and acyclic sulfone represented by R—SO ₂ —R ′ in claims 7, 16, and 23 of Patent Document 3. It is shown. In Patent Document 4, sulfur dioxide improves conductivity in all temperature ranges, and the protective film on the electrode is improved in the 30th paragraph, and the conductivity of the nonaqueous electrolyte is greatly improved. A method for dissolving and saturating sulfur dioxide in a nonaqueous electrolytic solution containing bis (trifluoromethanesulfonyl) imide lithium as a solute is disclosed in Example 3 of the 75th paragraph.
Neither document mentions the effect of sulfur dioxide on the high-temperature cycle characteristics. If a deterioration equivalent to the remarkable deterioration in high-temperature cycle characteristics occurs when CS and the like and high-concentration sulfur dioxide coexist, which has been found by the present inventors, will not be subjected to a high-temperature cycle test. In some cases, other basic battery tests are expected to be adversely affected. However, in both of the documents, the disclosed system to which sulfur dioxide is added (not a system in which CS or the like and sulfur dioxide coexist) has no adverse effect on basic battery tests. Therefore, it is very common to think that adding sulfur dioxide does not cause a decrease in battery performance.
However, in the case where sulfur dioxide is contained in the non-aqueous electrolyte together with the cyclic sulfonic anhydride derivative having two sulfonyl groups having the ethylene skeleton including CS, the performance of the non-aqueous electrolyte battery, particularly High temperature cycle characteristics are degraded. Although this is not clear in detail, it can be estimated as follows.

  A cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups is electrochemically decomposed to form SEI on the surface of the positive and negative electrodes, as in MMDS, etc. It seems that 60 degreeC high temperature cycling characteristic is improved by suppressing decomposition | disassembly of a solvent and elution of the metal in a positive electrode. Here, sulfur dioxide is electrochemically unstable as compared with a cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups, and begins to decompose at a lower potential. Therefore, SEI derived from sulfur dioxide is formed in the first stage at the first charge, and SEI derived from a cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups in the second stage. Will be formed. However, the electrochemical decomposition of the cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups does not proceed efficiently due to the influence of SEI derived from sulfur dioxide formed in the first stage. SEI is not sufficiently formed.

  When comparing SEI derived from sulfur dioxide and SEI derived from a cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups, the latter contains a carbon skeleton, and the latter is strong on the negative electrode surface by direct bonding or the like. In contrast, the former is not, but the former is peeled off in the process of charging and discharging, and the electrode protection performance is easily lost. As a result, in the high-temperature cycle test in which each is added, the performance is further reduced when sulfur dioxide is added. That is, when the cyclic sulfonic acid anhydride derivative having an ethylene skeleton and two sulfonyl groups contains a large amount of sulfur dioxide, and when the cyclic sulfonic acid anhydride derivative having an ethylene skeleton and two sulfonyl groups is included in the carbon dioxide. When compared with the case where a small amount of sulfur is contained, the latter is superior in high-temperature cycle characteristics. Furthermore, due to the influence of SEI derived from sulfur dioxide, the residue of cyclic sulfonic anhydride derivative having two sulfonyl groups with an ethylene skeleton that could not be decomposed electrochemically was chemically decomposed at 60 ° C. It can be assumed that the decomposition product has an adverse effect on the high-temperature cycle characteristics at 60 ° C.

［一般式（１）中、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４は、それぞれ互いに独立して水素、アルキル基、アルコキシ基、アルケニル基、アルケニルオキシ基、アルキニル基、アルキニルオキシ基、アリール基、及びアリールオキシ基からなる群から選ばれる基を示し、これらの基はフッ素原子、塩素原子、又は酸素原子を有していても良い。Ｃ^１−Ｒ^１ 間、またはＣ^２−Ｒ^２ 間が直接二重結合となる場合は、それぞれＲ^３，Ｒ^４は存在しない。また、以下の（２）、（４）に示す様に、Ｃ^１−Ｃ^２ 間に直接二重結合を形成しても良い。この場合、Ｒ^３、Ｒ^４は存在しない。また、（３）、（４）に示す様に、Ｒ^１、Ｒ^２が同一の環構造に含まれるような形をとっても良い。］

The present invention
(I) a non-aqueous organic solvent,
(II) a solute that is an ionic salt,
(III) An electrolyte for a non-aqueous electrolyte battery comprising a cyclic sulfonic anhydride derivative having two sulfonyl groups represented by the general formula (1),
The cyclic sulfonic anhydride derivative is
Starting from sulfur trioxide and a compound containing a double bond,
The content of sulfur dioxide, which is an impurity derived from the reaction between the sulfur trioxide and a compound containing a double bond, is 2.5% by mass or less.
This is an electrolyte for a non-aqueous electrolyte battery.

[In the general formula (1), R ¹ , R ² , R ³ and R ⁴ are each independently hydrogen, alkyl group, alkoxy group, alkenyl group, alkenyloxy group, alkynyl group, alkynyloxy group, aryl group. And a group selected from the group consisting of aryloxy groups, and these groups may have a fluorine atom, a chlorine atom, or an oxygen atom. In the case where a direct bond is formed between C ^{1 and} R ¹ or between C ^{2 and} R ² , R ³ and R ⁴ do not exist, respectively. Further, as shown in the following (2) and (4), a double bond may be directly formed between C ^{1 and} C ² . In this case, R ³ and R ⁴ do not exist. Further, as shown in (3) and (4), R ¹ and R ² may take the form of being included in the same ring structure. ]

  The sulfur dioxide content is preferably 2.0% by mass or less.

In addition, cyclic sulfonic anhydride derivatives having two sulfonyl groups represented by the general formula (1) are the following compound Nos. It is preferably at least one selected from the group consisting of 1 to 24.

  Moreover, it is preferable that the density | concentration of (III) with respect to the total amount of said (I) and (II) is 0.01 mass% or more and 10.0 mass% or less. More preferably, it is 0.05 mass% or more and 5.0 mass% or less, More preferably, it is the range of 0.1 mass% or more and 3.0 mass% or less. If the amount is less than 0.01% by mass, the effect of improving the characteristics of the non-aqueous battery cannot be sufficiently obtained. There is a possibility that the amount of sulfur increases and the high-temperature cycle characteristics at 60 ° C. deteriorate.

The ionic salt that is the solute is
At least one cation selected from the group consisting of lithium and sodium;
Hexafluorophosphate anion, tetrafluoroborate anion, difluorooxalatoborate anion, tetrafluorooxalatophosphate anion, trifluoromethanesulfonate anion, fluorosulfonate anion, bis (trifluoromethanesulfonyl) imide anion, bis (fluoro (Sulfonyl) imide anion, (trifluoromethanesulfonyl) (fluorosulfonyl) imide anion, bis (difluorophosphonyl) imide anion, (difluorophosphonyl) (fluorosulfonyl) imide anion, and (difluorophosphonyl) (trifluorosulfonyl) imide It is preferably an ionic salt composed of a pair of at least one anion selected from the group consisting of anions.

  The non-aqueous organic solvent is ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, methyl butyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, fluoroethylene carbonate, methyl acetate, ethyl acetate, propionic acid Methyl, ethyl propionate, methyl 2-fluoropropionate, ethyl 2-fluoropropionate, diethyl ether, acetonitrile, propionitrile, tetrahydrofuran, 2-methyltetrahydrofuran, furan, tetrahydropyran, 1,3-dioxane, 1,4 -Dioxane, dibutyl ether, diisopropyl ether, 1,2-dimethoxyethane, N, N-dimethylformamide, Methyl sulfoxide, sulfolane, and is preferably at least one selected from the group consisting of γ- butyrolactone, and γ- valerolactone.

The non-aqueous organic solvent preferably contains at least one selected from the group consisting of cyclic carbonates, chain carbonates, and esters.
At this time, the cyclic carbonate is at least one selected from the group consisting of ethylene carbonate, propylene carbonate, and butylene carbonate, and the chain carbonate is ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, ethyl And at least one selected from the group consisting of propyl carbonate and methyl butyl carbonate, and the ester is methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, methyl 2-fluoropropionate, and 2-fluoropropionic acid It is preferably at least one selected from the group consisting of ethyl.

In addition, (IV) other components may be further added to the non-aqueous electrolyte battery electrolyte of the present invention at an arbitrary ratio as long as the gist of the present invention is not impaired.
Therefore, the non-aqueous electrolyte battery electrolyte of the present invention is
further,
(IV) Other components include cyclohexylbenzene, cyclohexylfluorobenzene, biphenyl, difluoroanisole, t-butylbenzene, t-amylbenzene, 2-fluorotoluene, 2-fluorobiphenyl, vinylene carbonate, dimethyl vinylene carbonate, vinyl ethylene carbonate, fluoro Ethylene carbonate, difluoroethylene carbonate, ethynyl ethylene carbonate, divinyl ethylene carbonate, methyl difluoro vinyl silane, methyl fluoro divinyl silane, dimethyl divinyl silane, methyl trivinyl silane, tetra vinyl silane, maleic anhydride, succinic anhydride, succinonitrile, bisoxalato boron Lithium acid, sodium bisoxalatoborate, potassium bisoxalatoborate , Lithium difluorooxalatoborate, sodium difluorooxalatoborate, potassium difluorooxalatoborate, lithium tetrafluorooxalate, sodium tetrafluorooxalate, potassium tetrafluorooxalate, difluorobis (oxalato ) Lithium phosphate, sodium difluorobis (oxalato) phosphate, potassium difluorobis (oxalato) phosphate, lithium tris (oxalato) phosphate, sodium tris (oxalato) phosphate, potassium tris (oxalato) phosphate, difluorophosphate Lithium, lithium monofluorophosphate, lithium bis (trifluoromethanesulfonyl) imide, sodium bis (trifluoromethanesulfonyl) imide, bis (trifluoromethanes Phosphonyl) imide potassium, bis (fluorosulfonyl) imide lithium, bis (fluorosulfonyl) imide sodium, bis (fluorosulfonyl) imide potassium, (trifluoromethanesulfonyl) (fluorosulfonyl) imide lithium, (trifluoromethanesulfonyl) (fluorosulfonyl) Sodium imido, (trifluoromethanesulfonyl) (fluorosulfonyl) imide potassium, bis (difluorophosphonyl) imide lithium, bis (difluorophosphonyl) imide sodium, bis (difluorophosphonyl) imide potassium, (difluorophosphonyl) (fluorosulfonyl) ) Imidolithium, (difluorophosphonyl) (fluorosulfonyl) imido sodium, (difluorophosphonyl) (fluorosulphonyl) And (difluorophosphonyl) (trifluorosulfonyl) imide lithium, (difluorophosphonyl) (trifluorosulfonyl) imide sodium, and (difluorophosphonyl) (trifluorosulfonyl) imide potassium. The electrolyte solution for a nonaqueous electrolyte battery including at least one kind may be used.

  The above (IV) is vinylene carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, dimethyldivinylsilane, methyltrivinylsilane, tetravinylsilane, lithium bisoxalate borate, lithium difluorooxalatoborate, lithium tetrafluorooxalatophosphate, difluoro Lithium bis (oxalato) phosphate, lithium tris (oxalato) phosphate, lithium difluorophosphate, lithium monofluorophosphate, lithium bis (trifluoromethanesulfonyl) imide, lithium bis (fluorosulfonyl) imide, bis (difluorophosphonyl) It is preferably at least one selected from the group consisting of) imidolithium and (difluorophosphonyl) (fluorosulfonyl) imidolithium.

  The present invention also provides a positive electrode, a negative electrode made of lithium or a negative electrode material capable of occluding and releasing lithium, or a negative electrode made of sodium or a negative electrode material capable of occluding and releasing sodium, and the above electrolysis for non-aqueous electrolyte batteries. And a non-aqueous electrolyte battery.

  According to the present invention, an electrolyte solution for a non-aqueous electrolyte battery containing a cyclic sulfonic anhydride derivative having an ethylene skeleton and two sulfonyl groups, exhibiting high-temperature cycle characteristics equivalent to when MMDS is added, and A nonaqueous electrolyte battery using the same can be provided.

The graph of the discharge capacity maintenance factor with respect to sulfur dioxide content based on Examples 1-1 to 1-10 and Comparative Examples 1-1 to 1-6. The graph of the discharge capacity maintenance factor with respect to sulfur dioxide content based on Examples 2-1 to 2-15 and Comparative Examples 2-1 to 2-5.

  Configurations and combinations thereof in the following embodiments are examples, and additions, omissions, substitutions, and other modifications of the configurations can be made without departing from the spirit of the present invention. Further, the present invention is not limited by the embodiments, and is limited only by the scope of the claims.

(I) Nonaqueous organic solvent Examples of the nonaqueous organic solvent used in the electrolyte solution for a nonaqueous electrolyte battery of the present invention include carbonates, esters, ethers, lactones, nitriles, amides, and sulfones. Kind.

  Specific examples of the non-aqueous organic solvent include ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, methyl butyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, fluoroethylene carbonate, methyl acetate, ethyl acetate. , Methyl propionate, ethyl propionate, methyl 2-fluoropropionate, ethyl 2-fluoropropionate, diethyl ether, acetonitrile, propionitrile, tetrahydrofuran, 2-methyltetrahydrofuran, furan, tetrahydropyran, 1,3-dioxane, 1,4-dioxane, dibutyl ether, diisopropyl ether, 1,2-dimethoxyethane, N, N-dimethylphenol Muamido, dimethyl sulfoxide, sulfolane, .gamma.-butyrolactone, and .gamma.-valerolactone.

  It is preferable that the non-aqueous organic solvent is at least one selected from the group consisting of cyclic carbonates and chain carbonates from the viewpoint of excellent cycle characteristics at high temperatures. Moreover, it is preferable that the non-aqueous organic solvent is at least one selected from the group consisting of esters because of excellent input / output characteristics at low temperatures. Specific examples of the cyclic carbonate include ethylene carbonate, propylene carbonate, and butylene carbonate. Specific examples of the chain carbonate include ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, and methyl. Examples include butyl carbonate. Specific examples of the ester include methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, methyl 2-fluoropropionate, and ethyl 2-fluoropropionate.

  The electrolyte solution for a non-aqueous electrolyte battery of the present invention may contain a polymer, and may be generally called a polymer solid electrolyte. The polymer solid electrolyte includes those containing a non-aqueous organic solvent as a plasticizer.

  The polymer is not particularly limited as long as it is an aprotic polymer capable of dissolving the above (II) and (III). Examples thereof include polymers having polyethylene oxide in the main chain or side chain, homopolymers or copolymers of polyvinylidene fluoride, methacrylic acid ester polymers, polyacrylonitrile and the like. When adding a plasticizer to these polymers, an aprotic nonaqueous organic solvent is used among the above nonaqueous organic solvents.

(II) Solute As the solute used in the electrolyte for a non-aqueous electrolyte battery of the present invention, for example,
At least one cation selected from the group consisting of an alkali metal cation and an alkaline earth metal cation;
Hexafluorophosphate anion, tetrafluoroborate anion, hexafluoroarsenate anion, hexafluoroantimonate anion, difluorooxalatoborate anion, dioxalate borate anion, tetrafluorooxalatophosphate anion, trioxalatrate anion, trifluoro Lomethanesulfonate anion, fluorosulfonate anion, bis (trifluoromethanesulfonyl) imide anion, bis (pentafluoroethanesulfonyl) imide anion, (trifluoromethanesulfonyl) (pentafluoroethanesulfonyl) imide anion, bis (fluorosulfonyl) imide anion , (Trifluoromethanesulfonyl) (fluorosulfonyl) imide anion, (pentafluoroethanesulfonyl) (fluoro The group consisting of a sulfonyl) imide anion, a tris (trifluoromethanesulfonyl) methide anion, a bis (difluorophosphonyl) imide anion, a (difluorophosphonyl) (fluorosulfonyl) imide anion, and a (difluorophosphonyl) (trifluorosulfonyl) imide anion An ionic salt composed of a pair with at least one anion selected from
Among them, at least one cation selected from the group consisting of lithium and sodium,
Hexafluorophosphate anion, tetrafluoroborate anion, difluorooxalatoborate anion, tetrafluorooxalatophosphate anion, trifluoromethanesulfonate anion, fluorosulfonate anion, bis (trifluoromethanesulfonyl) imide anion, bis (fluoro (Sulfonyl) imide anion, (trifluoromethanesulfonyl) (fluorosulfonyl) imide anion, bis (difluorophosphonyl) imide anion, (difluorophosphonyl) (fluorosulfonyl) imide anion, and (difluorophosphonyl) (trifluorosulfonyl) imide It is preferably an ionic salt composed of a pair of at least one anion selected from the group consisting of anions.

  The concentration of these solutes is not particularly limited, but the lower limit is 0.5 mol / L or more, preferably 0.7 mol / L or more, more preferably 0.9 mol / L or more, and the upper limit is 2.5 mol / L. / L or less, preferably 2.2 mol / L or less, more preferably 2.0 mol / L or less. If it is less than 0.5 mol / L, the ionic conductivity is lowered, so that the cycle characteristics and output characteristics of the nonaqueous electrolyte battery are lowered. On the other hand, if it exceeds 2.5 mol / L, the electrolyte solution for the nonaqueous electrolyte battery is If the viscosity increases, the ionic conduction may be lowered, and the cycle characteristics and output characteristics of the nonaqueous electrolyte battery may be degraded. These solutes may be used alone or in combination.

  When a large amount of the solute is dissolved in the non-aqueous organic solvent at one time, the temperature of the non-aqueous electrolyte may increase due to the heat of dissolution of the solute, and when the temperature of the solution increases significantly, the decomposition of the solute and the solvent proceeds. This is not preferable because it may cause coloring or performance deterioration of the electrolyte for nonaqueous electrolyte batteries. For this reason, although the liquid temperature at the time of melt | dissolving this solute in a non-aqueous organic solvent is not specifically limited, -20-55 degreeC is preferable and 0-45 degreeC is more preferable.

(III) It is produced by a conventional method in which sulfur trioxide and a compound containing a double bond are reacted, and the content of sulfur dioxide contained as an impurity derived from the reaction is 2.5% by mass or less. Regarding the cyclic sulfonic anhydride derivative having two sulfonyl groups represented by 1) As specific examples of the cyclic sulfonic anhydride derivative having two sulfonyl groups represented by the general formula (1), the following compound No. 1 is used. 1-24 are mentioned.

It is important that the sulfur dioxide content in the cyclic sulfonic anhydride derivative having two sulfonyl groups represented by the general formula (1) is 2.5% by mass or less.
When the content is 2.5% by mass or less, the effect of improving the high-temperature cycle characteristics at 60 ° C. of (III) is not impaired (high temperature cycle characteristics equivalent to or higher than when MMDS is added). The content is preferably as low as possible, more preferably 2.0% by mass or less, still more preferably 0.5% by mass or less, and particularly preferably 0.01% by mass or less. The content of sulfur dioxide is most preferably 0% by mass, but its complete removal causes manufacturing problems such as an increase in the number of processes and a prolonged process, and problems in the accuracy of quantitative analysis of sulfur dioxide. Become.
In addition, the sulfur dioxide content in the cyclic sulfonic anhydride derivative having two sulfonyl groups represented by the general formula (1) is converted into sodium sulfite by adding, for example, an aqueous sodium hydroxide solution. It can be measured by quantifying the amount of iodine consumed when it is oxidized with iodine.

  The cyclic sulfonic anhydride derivative having two sulfonyl groups represented by the general formula (1) is obtained, for example, by mixing a compound having a double bond and sulfur trioxide and heating. For example, the content of sulfur dioxide in the derivative can be reduced to 2.5% by mass or less by heating to 60 ° C. or more and blowing dry nitrogen, performing sublimation purification, or recrystallization. .

(IV) Other components As long as the gist of the present invention is not impaired, additive components generally used in the electrolyte solution for a non-aqueous electrolyte battery of the present invention may be further added at an arbitrary ratio. As a specific example,
Cyclohexylbenzene, cyclohexylfluorobenzene, biphenyl, difluoroanisole, t-butylbenzene, t-amylbenzene, 2-fluorotoluene, 2-fluorobiphenyl, vinylene carbonate, dimethyl vinylene carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, difluoroethylene carbonate , Ethynyl ethylene carbonate, divinyl ethylene carbonate, methyl difluoro vinyl silane, methyl fluoro divinyl silane, dimethyl divinyl silane, methyl trivinyl silane, tetra vinyl silane, maleic anhydride, succinic anhydride, succinonitrile, lithium bisoxalatoborate, bisoxalato boron Sodium phosphate, potassium bisoxalatoborate, difluorooxalato Lithium oxalate, sodium difluorooxalatoborate, potassium difluorooxalatoborate, lithium tetrafluorooxalatotrinate, sodium tetrafluorooxalatophosphate, potassium tetrafluorooxalatophosphate, lithium difluorobis (oxalato) phosphate , Sodium difluorobis (oxalato) phosphate, potassium difluorobis (oxalato) phosphate, lithium tris (oxalato) phosphate, sodium tris (oxalato) phosphate, potassium tris (oxalato) phosphate, lithium difluorophosphate, monofluoro Lithium phosphate, bis (trifluoromethanesulfonyl) imide lithium, bis (trifluoromethanesulfonyl) imide sodium, bis (trifluoromethanesulfonyl) imide potassium Bis (fluorosulfonyl) imide lithium, bis (fluorosulfonyl) imide sodium, bis (fluorosulfonyl) imide potassium, (trifluoromethanesulfonyl) (fluorosulfonyl) imide lithium, (trifluoromethanesulfonyl) (fluorosulfonyl) imide sodium, (trifluoro Lomethanesulfonyl) (fluorosulfonyl) imide potassium, bis (difluorophosphonyl) imide lithium, bis (difluorophosphonyl) imide sodium, bis (difluorophosphonyl) imide potassium, (difluorophosphonyl) (fluorosulfonyl) imide lithium, Difluorophosphonyl) (fluorosulfonyl) imide sodium, (difluorophosphonyl) (fluorosulfonyl) imide potassium, (di Overcharge prevention effect such as fluorophosphonyl) (trifluorosulfonyl) imide lithium, (difluorophosphonyl) (trifluorosulfonyl) imide sodium and (difluorophosphonyl) (trifluorosulfonyl) imide potassium, Examples thereof include compounds having a positive electrode protective effect.
Among them, the above (IV) is vinylene carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, dimethyldivinylsilane, methyltrivinylsilane, tetravinylsilane, lithium bisoxalate borate, lithium difluorooxalate, lithium tetrafluorooxalate. , Lithium difluorobis (oxalato) phosphate, lithium tris (oxalato) phosphate, lithium difluorophosphate, lithium monofluorophosphate, lithium bis (trifluoromethanesulfonyl) imide, lithium bis (fluorosulfonyl) imide, bis (difluoro When selected from (phosphonyl) imidolithium and (difluorophosphonyl) (fluorosulfonyl) imidolithium, the high-temperature cycle characteristics are further improved. It preferred for easy to.
Moreover, it is also possible to use the non-aqueous electrolyte battery electrolyte in a quasi-solid state with a gelling agent or a crosslinked polymer, as in the case of use in a non-aqueous electrolyte battery called a polymer battery.

  In addition, in the specific example of the above (II) and the specific example of the above (IV), there are some overlapping, but when used as (II), the content is 0.5 to 2.5 mol / L. It is preferable that when used as (IV), the content is preferably 0.02 to 10.0% by mass. Moreover, when using the same compound as (II) and (IV), respectively, it is preferable that content which added both is 0.5-2.5 mol / L.

About the non-aqueous electrolyte battery The non-aqueous electrolyte battery of the present invention includes a positive electrode, a negative electrode made of lithium or a negative electrode material capable of occluding and releasing lithium, the non-aqueous electrolyte battery electrolyte, a current collector, Consists of separators, containers, etc. Or the battery of this invention consists of a positive electrode, the negative electrode which consists of a negative electrode material which can occlude / release sodium or sodium, the said electrolyte solution for non-aqueous electrolyte batteries, a collector, a separator, a container, etc.

About the positive electrode The positive electrode is composed of a positive electrode active material, a current collector containing aluminum, a conductive material, and a binder. The type of the positive electrode active material is not particularly limited, but alkali metal ions such as lithium ions and sodium ions, or A material in which alkaline earth metal ions can be reversibly inserted and removed is used.

When the cation is lithium, as the positive electrode active material, lithium-containing transition metal composite oxides such as LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , LiMn ₂ O ₄ , Co, Mn, Ni, etc. of those lithium-containing transition metal composite oxides A mixture of a plurality of transition metals, a part of the transition metal of the lithium-containing transition metal composite oxide substituted with a metal other than the transition metal, TiO ₂ , V ₂ O ₅ , MoO _3, etc. Oxides, sulfides such as TiS ₂ and FeS, conductive polymers such as polyacetylene, polyparaphenylene, polyaniline, and polypyrrole, activated carbon, polymers that generate radicals, and carbon materials are used.

About the negative electrode The negative electrode comprises a negative electrode active material, a current collector, a conductive material, and a binder. The type of the negative electrode active material is not particularly limited, but alkali metal ions such as lithium ions and sodium ions, or alkaline earths. A material capable of reversibly inserting and removing metal ions is used.

  When the cation is lithium, as the negative electrode active material, lithium metal, alloys of lithium and other metals and intermetallic compounds, various carbon materials capable of inserting and extracting lithium, metal oxides, metal nitrides, Activated carbon, conductive polymer, etc. are used. Examples of the carbon material include graphitizable carbon, non-graphitizable carbon (also referred to as hard carbon) having a (002) plane spacing of 0.37 nm or more, and a (002) plane spacing of 0. And graphite of 37 nm or less, and the latter is made of artificial graphite or natural graphite.

Conductive Material and Binder For the positive electrode and the negative electrode, acetylene black, ketjen black, furnace black, carbon fiber, graphite, fluorinated graphite, etc. are used as the conductive material. In addition, as a binder, polytetrafluoroethylene, polyvinylidene fluoride (hereinafter referred to as PVDF), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, styrene butadiene rubber, carboxymethyl cellulose, methyl cellulose, cellulose acetate phthalate, hydroxypropyl methylcellulose, polyvinyl alcohol Etc. are used.

  A solution obtained by dissolving or dispersing an active material (positive electrode or negative electrode), a conductive material, and a binder in an organic solvent or water is applied and dried on a copper foil for a negative electrode, for example, on an aluminum foil for a positive electrode. -By pressing, an electrode sheet molded into a sheet is obtained.

  As a separator for preventing contact between the positive electrode and the negative electrode, a nonwoven fabric or a porous sheet made of polypropylene, polyethylene, cellulose, glass fiber or the like is used.

  From the above elements, an electrochemical device having a shape such as a coin shape, a cylindrical shape, a square shape, or an aluminum laminate sheet type is assembled.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention does not receive a restriction | limiting at all in these description.

[Production of LCO positive electrode]
Mixing 90% by mass of LiCoO ₂ powder with 5% by mass of PVDF as a binder and 5% by mass of acetylene black as a conductive material, and further adding N-methyl-2-pyrrolidone (hereinafter NMP), Produced. This paste was applied on an aluminum foil, dried and pressurized, and then punched into a circle having a diameter of 15.5 mm to obtain a test LCO positive electrode.

[Production of NCM positive electrode]
Mixing 90% by mass of LiNi _1/3 Mn _1/3 Co _1/3 O ₂ powder, 5% by mass of PVDF as a binder, 5% by mass of acetylene black as a conductive material, and further adding NMP, a positive electrode mixture paste Was made. This paste was applied on an aluminum foil, dried and pressurized, and then punched into a circle having a diameter of 15.5 mm to obtain a test NCM positive electrode.

[Production of LFP positive electrode]
90% by mass of LiFePO ₄ powder coated with amorphous carbon was mixed with 5% by mass of PVDF as a binder and 5% by mass of acetylene black as a conductive material, and further NMP was added to prepare a positive electrode mixture paste. This paste was applied onto an aluminum foil, dried and pressurized, and then punched into a circle having a diameter of 15.5 mm to obtain a test LFP positive electrode.

(Production of graphite negative electrode)
90% by mass of graphite powder was mixed with 10% by mass of PVDF as a binder, and NMP was further added to prepare a negative electrode mixture paste. This paste was applied on a copper foil, dried and pressed, and then punched into a circle having a diameter of 15.5 mm to obtain a test graphite negative electrode.

[Production of silicon negative electrode]
Mixed with 70% by mass of simple silicon powder, 15% by mass of Dream Bond (manufactured by IST Co., Ltd.) as a binder, 15% by mass of acetylene black as a conductive material, NMP is further added, and negative electrode mixture paste Was made. This paste was applied onto a copper foil, dried and pressurized, and then punched into a predetermined size to obtain a test silicon negative electrode.

[Production of non-aqueous electrolyte battery]
A test negative electrode using each of the above active materials (LCO / NCM / LFP) and a test graphite negative electrode using each of the above active materials (graphite / silicon) in an argon atmosphere with a dew point of −50 ° C. or less; A laminate type cell (300 mAh) was assembled using a polyethylene separator impregnated with an electrolyte prepared in Examples and Comparative Examples described later, and an aluminum laminate film.

(Initial charge / discharge)
The assembled cell was put into a 25 degreeC thermostat, and it connected with the charging / discharging apparatus in the state. The battery was charged up to the upper limit voltage shown in Table 1 at a charge rate of 0.2 C (current value at which discharge of a cell with a capacity value normalized by the amount of the positive electrode active material was completed in 5 hours). After reaching the upper limit voltage, the voltage was maintained for 1 hour and then discharged to the lower limit voltage shown in Table 1 at a discharge rate of 0.2C. The discharge capacity obtained at this time was defined as the initial discharge capacity. This was defined as one charge / discharge cycle, and a total of three charge / discharge cycles were performed to stabilize the cell.

[High temperature cycle test]
The temperature of the thermostat was set to 60 ° C., and after the temperature was sufficiently stabilized, the battery was charged to the upper limit voltage shown in Table 1 at a charge rate of 2C. After reaching the upper limit voltage, the voltage was maintained for 1 hour and then discharged to the lower limit voltage shown in Table 1 at a discharge rate of 2C. This charge and discharge at 2C in an environment of 60 ° C. was repeated 500 cycles. Then, the degree of deterioration of the cell was evaluated based on the discharge capacity maintenance rate after 500 cycles (high temperature cycle characteristic evaluation). The discharge capacity retention rate was determined by the following formula.
[Discharge capacity maintenance rate after 500 cycles]
Discharge capacity retention rate (%) = (discharge capacity after 500 cycles / initial discharge capacity) × 100

(Preparation of basic composition non-aqueous electrolyte)
(Basic composition non-aqueous electrolyte A)
In a glove box filled with argon with a dew point of -50 ° C or lower,
(I) For a mixed solvent (1: 2 by volume) of ethylene carbonate (hereinafter EC) and ethyl methyl carbonate (hereinafter EMC),
(II) Lithium hexafluorophosphate (hereinafter LiPF ₆ ) was added to a concentration of 1.0 mol / L and completely dissolved. At this time, the addition rate at which the liquid temperature did not exceed 45 ° C. was maintained. This is designated as a basic composition non-aqueous electrolyte A.

(Basic composition non-aqueous electrolyte B)
In a glove box filled with argon with a dew point of -50 ° C or lower,
(I) For a mixed solvent of EC, dimethyl carbonate (hereinafter DMC) and ethyl propionate (hereinafter PE) (1: 1: 1 by volume),
(II) LiPF ₆ was added to a concentration of 1.0 mol / L and completely dissolved. At this time, the addition rate at which the liquid temperature did not exceed 45 ° C. was maintained. This is designated as a basic composition non-aqueous electrolyte B.

(Basic composition non-aqueous electrolyte C)
Bis (fluorosulfonyl) imidolithium (hereinafter referred to as LiFSI) was synthesized by the method disclosed in Example 2 of Patent Document 5 in which sulfuryl fluoride and anhydrous ammonia were reacted and cation exchange was performed with lithium hydroxide.
In a glove box filled with argon with a dew point of -50 ° C or lower,
(I) For a mixed solvent of EC and EMC (volume ratio 1: 2),
(II) LiPF ₆ was added to a concentration of 0.50 mol / L, and LiFSI was added to a concentration of 0.50 mol / L (the total concentration of solutes as ionic salts was 1.0 mol / L) and completely dissolved. . At this time, the addition rate at which the liquid temperature did not exceed 45 ° C. was maintained. This is designated as a basic composition non-aqueous electrolyte C.

(Basic composition non-aqueous electrolyte D)
In a glove box filled with argon with a dew point of -50 ° C or lower,
(I) For a mixed solvent of EC, EMC and fluoroethylene carbonate (hereinafter FEC) (3: 8: 1 by volume),
(II) LiPF ₆ was added to a concentration of 1.0 mol / L and completely dissolved. At this time, the addition rate at which the liquid temperature did not exceed 45 ° C. was maintained. This is designated as a basic composition non-aqueous electrolyte D.

[Measurement of sulfur dioxide content]
A compound to be measured is completely hydrolyzed with a 1.0 M aqueous sodium hydroxide solution, and then an iodine solution (0.1 M) is added to form sulfurous acid produced by sulfur dioxide and sodium hydroxide contained in the compound. Sodium was completely oxidized. Next, back titration was performed using a sodium thiosulfate solution (0.1 M), the amount of consumed iodine was determined, and the content of sulfur dioxide contained in the compound was calculated from this value. When the sulfur dioxide concentration was less than 0.1% by mass, a 0.01M iodine solution and a 0.01M sodium thiosulfate solution were used.

[(III) Preparation of Compound Shown by General Formula (1)]
(Compound No. 1)
When the synthesis was carried out by a method of reacting a predetermined amount of ethylene and sulfur trioxide shown in the experimental section (Carbyl Sulfate) of Non-Patent Document 2, the purity was 96.2% by mass and the sulfur dioxide content was Compound No. 3.1% by mass and other impurities of 0.7% by mass 1 (33.4 g) was obtained. Although the structure of other impurities is unknown, it can be estimated from H-NMR that the compound is derived from raw material ethylene. Of this, 22.5 g was added to a 100 mL glass two-necked flask container that had been dried at 150 ° C. for 24 hours and then cooled to 25 ° C. under a nitrogen stream with a dew point of −75 ° C. After raising the internal temperature of the flask to 80 ° C., nitrogen having a dew point of −75 ° C. was introduced from one mouth of the two-necked flask (5 mL / min), and extracted from the other mouth to the outside. When the introduction of nitrogen was stopped after 2 hours and a part of the content was taken out, compound No. having a purity of 97.5% by mass, a sulfur dioxide content of 1.8% by mass and other impurities of 0.7% by mass . 1 was obtained. When the introduction of nitrogen was restarted and further measured after 3 hours, the compound No. 1 had a purity of 99.1% by mass, a sulfur dioxide content of 0.2% by mass and other impurities of 0.7% by mass. 1 was obtained.
The remaining compound No. having a sulfur dioxide content of 3.1% by mass was used. 1 (10.2 g) was added to a similarly dried 100 mL glass two-necked flask container, and after raising the internal temperature of the flask to 80 ° C., nitrogen at a dew point of −75 ° C. was added from one end of the two-necked flask. It was introduced (2 mL / min) and extracted outside through the other mouth. When the introduction of nitrogen was stopped after 2 hours and a part of the content was taken out, Compound No. having a purity of 96.5% by mass, a sulfur dioxide content of 2.8% by mass, and other impurities of 0.7% by mass . 1 was obtained. When the introduction of nitrogen was restarted and further measured after 2 hours, the compound No. 1 had a purity of 96.9% by mass, a sulfur dioxide content of 2.4% by mass and other impurities of 0.7% by mass. 1 was obtained.
Compound No. 2 having a sulfur dioxide content of 0.2% by mass. 1 was dissolved in a minimum amount of chloroform heated to 50 ° C., and then the liquid temperature was cooled to 5 ° C. at a temperature lowering rate of 5 ° C./h. When the obtained precipitate was recovered by filtration, the compound No. 1 had a purity of 99.3% by mass, a sulfur dioxide content of less than 0.01% by mass, and other impurities of 0.7% by mass. 1 was obtained (the lower limit of detection of the sulfur dioxide concentration measurement method described above is 0.01% by mass).

(Compound No. 2)
The raw material was changed from ethylene to isobutene (manufactured by Tokyo Kasei Kogyo Co., Ltd.) with reference to a method for reacting a predetermined amount of ethylene and sulfur trioxide, which is shown in the experimental section (Carbyl Sulfate) of Non-Patent Document 2. As a result of the synthesis, compound No. 1 having a purity of 96.3% by mass, a sulfur dioxide content of 3.2% by mass and other impurities of 0.5% by mass was obtained. 2 was obtained. As above, heating to 80 ° C. and introducing nitrogen at a dew point of −75 ° C. for 2 hours (5 mL / min) gave a purity of 98.0% by mass, sulfur dioxide content of 1.5% by mass, and other impurities of 0.5%. Compound No. which is mass%. 2 further added nitrogen introduction for 3 hours to obtain a compound No. 2 having a purity of 99.0% by mass, a sulfur dioxide content of 0.5% by mass, and other impurities of 0.5% by mass. 2 was obtained.
Compound No. 2 having a sulfur dioxide content of 3.2% by mass. 2 was added to a similarly dried 100 mL glass two-necked flask container, and the flask internal temperature was raised to 80 ° C., and then nitrogen at a dew point of −75 ° C. was introduced from one mouth of the two-necked flask (2 mL / Min) and pulled out from the other mouth. When the introduction of nitrogen was stopped after 2 hours and a part of the content was taken out, compound No. having a purity of 96.8% by mass, a sulfur dioxide content of 2.7% by mass, and other impurities of 0.5% by mass . 2 was obtained. When the introduction of nitrogen was restarted and further measured after 2 hours, the compound No. 1 had a purity of 97.2% by mass, a sulfur dioxide content of 2.3% by mass and other impurities of 0.5% by mass. 2 was obtained.

(Compound No. 6)
The raw material was changed from ethylene to cyclohexene (manufactured by Tokyo Kasei Kogyo Co., Ltd.) with reference to a method of reacting a predetermined amount of ethylene and sulfur trioxide, which is shown in the experimental section (Carbyl Sulfate) of Non-Patent Document 2. As a result of the synthesis, compound No. 1 having a purity of 94.1% by mass, a sulfur dioxide content of 5.0% by mass, and other impurities of 0.9% by mass were obtained. 6 was obtained. As above, by heating to 80 ° C. and introducing nitrogen at a dew point of −75 ° C. for 2 hours (5 mL / min), the purity was 97.2 mass%, the sulfur dioxide content was 1.9 mass%, and other impurities were 0.9 Compound No. which is mass%. No. 6 is a compound No. 6 having a purity of 98.8% by mass, sulfur dioxide content of 0.3% by mass, and other impurities of 0.9% by mass by further introducing nitrogen for 3 hours. 6 was obtained.
Compound No. 2 having a sulfur dioxide content of 5.0% by mass. 2 was added to a similarly dried 100 mL glass two-necked flask container, and the flask internal temperature was raised to 80 ° C., and then nitrogen at a dew point of −75 ° C. was introduced from one mouth of the two-necked flask (2 mL / Min) and pulled out from the other mouth. After 6 hours, when the introduction of nitrogen was stopped and a part of the content was taken out, the compound No. having a purity of 96.3% by mass, a sulfur dioxide content of 2.8% by mass, and other impurities of 0.9% by mass . 6 was obtained. When the introduction of nitrogen was restarted and further measured after 2 hours, the compound No. 1 had a purity of 96.7% by mass, a sulfur dioxide content of 2.4% by mass and other impurities of 0.9% by mass. 6 was obtained.

[(IV) Preparation of other ingredients]
(Vinylene carbonate “VC”)
A product made by Aldrich was used.

(Lithium bisoxalatoborate, "LBOB")
What was obtained by the method of reacting oxalic acid and lithium tetrafluoroborate in the presence of silicon tetrachloride disclosed in Example 6 of Patent Document 6 was dissolved in DMC and recrystallized and purified. I used something.

(Lithium difluorobis (oxalato) borate hereinafter referred to as “LDFBOP”)
What was obtained by the method of reacting a predetermined amount of oxalic acid and lithium tetrafluoroborate in the presence of silicon tetrachloride disclosed in Example 1 of Patent Document 6 was dissolved in EMC and then cis- 1-Chloro-3,3,3-trifluoro-1-propene (manufactured by Central Glass) was used for reprecipitation purification.

(Lithium tris (oxalato) phosphate "LTOP")
As shown in the experimental section of Non-Patent Document 3, a predetermined amount of oxalic acid and phosphorus pentachloride reacted in a diethyl ether solvent and then manufactured by a method of neutralizing with lithium hydride was used. .

(Lithium difluorophosphate "LDFP")
After obtaining an EMC solution containing 2.7% by mass of lithium difluorophosphate by the method of reacting LiPF ₆ with water and lithium chloride, disclosed in Example 1 of Patent Document 7, concentration was further performed. It was. Then, the precipitated lithium difluorophosphate was collected by filtration, dissolved in ethyl acetate, and recrystallized and purified.

(Bis (difluorophosphonyl) imidolithium hereinafter "LBDFA")
Bis (difluorophosphonyl) imide potassium was produced by the method of reacting potassium fluoride and bis (dichlorophosphoryl) imide disclosed in Example 5 of Patent Document 8. 500 g of Dow Chemical's strongly acidic cation exchange resin 252 (hereinafter referred to as ion exchange resin) was weighed and immersed in a 0.1 N aqueous lithium hydroxide solution (2.5 kg) and stirred at 25 ° C. for 6 hours. The ion exchange resin was collected by filtration and washed thoroughly with pure water until the pH of the washing solution was 8 or less. Thereafter, moisture was removed by drying under reduced pressure (120 ° C., 1.3 kPa) for 12 hours.
Prepare an EMC solution so that the concentration of potassium bis (difluorophosphonyl) imide is 10% by mass, add the dried ion exchange resin half the weight of the solution, and stir at 25 ° C. for 6 hours. Went. Thereafter, by removing the ion exchange resin by filtration, LBDFA in which the cation was exchanged from potassium to lithium was obtained. When the cation was quantified by ion chromatography, the lithium / potassium ratio was 99.3.

(Methyltrivinylsilane "TVSI")
The Gelest product was purified by distillation to a purity of 99% or higher.

(Succinonitrile "SUNI")
A product made by Aldrich (purity 99%) was used.

[Preparation of test solution]
(Test solution 1)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 1 was prepared by dissolving 1 (sulfur dioxide content less than 0.01% by mass).

(Test solution 2)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 2 was prepared by dissolving 1 (sulfur dioxide content 0.2 mass%).

(Test solution 3)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 3 was prepared by dissolving 1 (sulfur dioxide content 1.8% by mass).

(Test solution 4)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 4 was prepared by dissolving 1 (sulfur dioxide content 2.4 mass%).

(Test solution 5)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 5 was prepared by dissolving 1 (sulfur dioxide content 2.8% by mass).

(Test solution 6)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 6 was prepared by dissolving 1 (sulfur dioxide content 3.1 mass%).

(Test solution 7)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 7 was prepared by dissolving 2 (sulfur dioxide content 0.5 mass%).

(Test solution 8)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 8 was prepared by dissolving 2 (sulfur dioxide content 1.5 mass%).

(Test solution 9)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 9 was prepared by dissolving 2 (sulfur dioxide content 2.3 mass%).

(Test solution 10)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 10 was prepared by dissolving 2 (sulfur dioxide content 2.7% by mass).

(Test solution 11)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 11 was prepared by dissolving 2 (sulfur dioxide content 3.2 mass%).

(Test solution 12)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 12 was prepared by dissolving 6 (sulfur dioxide content 0.3 mass%).

(Test solution 13)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 13 was prepared by dissolving 6 (sulfur dioxide content 1.9% by mass).

(Test solution 14)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 14 was prepared by dissolving 6 (sulfur dioxide content 2.4 mass%).

(Test solution 15)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 15 was prepared by dissolving 6 (sulfur dioxide content 2.8% by mass).

(Test solution 16)
In the basic composition non-aqueous electrolyte A, as the component (III), Compound No. Test solution 16 was prepared by dissolving 6 (sulfur dioxide content 5.0 mass%).

(Test solution 17)
In the basic composition non-aqueous electrolyte B, as the component (III), the compound no. Test solution 17 was prepared by dissolving 1 (sulfur dioxide content 0.2 mass%).

(Test Solution 18)
In the basic composition non-aqueous electrolyte B, as the component (III), the compound no. Test solution 18 was prepared by dissolving 1 (sulfur dioxide content 1.8% by mass).

(Test solution 19)
In the basic composition non-aqueous electrolyte B, as the component (III), the compound no. Test solution 19 was prepared by dissolving 1 (sulfur dioxide content 2.4 mass%).

(Test solution 20)
In the basic composition non-aqueous electrolyte B, as the component (III), the compound no. Test solution 20 was prepared by dissolving 1 (sulfur dioxide content 2.8 mass%).

(Test solution 21)
In the basic composition non-aqueous electrolyte C, as the component (III), Compound No. Test liquid 21 was prepared by dissolving 1 (sulfur dioxide content 0.2 mass%).

(Test solution 22)
In the basic composition non-aqueous electrolyte C, as the component (III), Compound No. Test solution 22 was prepared by dissolving 1 (sulfur dioxide content 1.8% by mass).

(Test Solution 23)
In the basic composition non-aqueous electrolyte C, as the component (III), Compound No. Test solution 23 was prepared by dissolving 1 (sulfur dioxide content 2.4 mass%).

(Test solution 24)
In the basic composition non-aqueous electrolyte C, as the component (III), Compound No. Test solution 24 was prepared by dissolving 1 (sulfur dioxide content 2.8% by mass).

(Test solution 25)
In the basic composition non-aqueous electrolyte D, as the component (III), the compound No. Test solution 25 was prepared by dissolving 1 (sulfur dioxide content 0.2 mass%).

(Test solution 26)
In the basic composition non-aqueous electrolyte D, as the component (III), the compound No. Test solution 26 was prepared by dissolving 1 (sulfur dioxide content 1.8% by mass).

(Test solution 27)
In the basic composition non-aqueous electrolyte D, as the component (III), the compound No. Test solution 27 was prepared by dissolving 1 (sulfur dioxide content 2.4 mass%).

(Test solution 28)
In the basic composition non-aqueous electrolyte D, as the component (III), the compound No. Test solution 28 was prepared by dissolving 1 (sulfur dioxide content 2.8% by mass).

[Example 1-1]
Using test solution 1, a non-aqueous electrolyte battery was produced as described above (positive electrode NCM / negative electrode graphite), and after further cell stabilization, a high-temperature cycle test was conducted, and the obtained discharge capacity retention rate (% ) Are shown in Table 2 and FIG. 1 as relative values when the value of Reference Example 1-1 is taken as 100.

[Examples 1-2 to 1-10, Comparative Examples 1-1 to 1-6]
A nonaqueous electrolyte battery was prepared and evaluated in the same manner as in Example 1-1 except that the test solution as shown in Table 2 was used. The results are shown in Table 2 and FIG.

[Reference Example 1-1]
Instead of adding the component (III) to the basic composition non-aqueous electrolyte A, instead of dissolving methylenemethane disulfonate (MMDS) to a concentration of 1.0% by mass, Reference Example 1-1 A test solution according to was prepared. As the MMDS, the one obtained by the method of reacting sodium methanedisulfonate, concentrated sulfuric acid, phosphorus pentoxide and paraformaldehyde disclosed in Patent Document 2 was used.

  Compound No. Comparison is made with the system to which 1 is added. Compound No. When the content of sulfur dioxide contained in 1 is 2.8% by mass (Comparative Example 1-1) or 3.1% by mass (Comparative Example 1-2), a system using MMDS (Reference Example 1-1) The discharge capacity retention rate is significantly lower than that of No. 1, and is less than 80% based on Reference Example 1-1. However, in Example 1-4 (the content of sulfur dioxide is 2.4% by mass) in which the content of sulfur dioxide is 2.5% by mass or less, the discharge capacity maintenance ratio is 95 based on Reference Example 1-1. % And 60 ° C. high temperature cycle characteristics equivalent to those of Reference Example 1-1 were confirmed. Furthermore, when the content of sulfur dioxide was 2.0% by mass or less, it was confirmed that the discharge capacity retention ratio exceeded the value of Reference Example 1-1. Moreover, the content of sulfur dioxide is 1.8% by mass (Example 1-3), 0.2% by mass (Example 1-2), less than 0.01% by mass (Example 1-1), It was confirmed that as the amount decreased, a better discharge capacity retention rate was obtained.

  The additive is compound No. 1 to compound no. 2 and compound no. Similarly, when the amount is changed to 6, the content of sulfur dioxide is reduced to 2.5% by mass or less, so that the discharge capacity retention rate is 85% or more based on the system using MMDS (Reference Example 1-1). Was confirmed to achieve. Furthermore, when the content of sulfur dioxide was 2.0% by mass or less, it was confirmed that the discharge capacity retention rate achieved 90% or more based on Reference Example 1-1. Moreover, the tendency for the more excellent discharge capacity maintenance factor to be obtained was confirmed, so that there was little content of sulfur dioxide.

As is clear from FIG. 1, the sulfur dioxide content and the discharge capacity retention ratio are not proportional.
In the region where the sulfur dioxide content exceeds 2.5% by mass, the discharge capacity retention rate based on the system using MMDS (Reference Example 1-1) is greatly reduced as the sulfur dioxide content increases. .
On the other hand, in the region where the content of sulfur dioxide is 2.5% by mass or less, the discharge capacity maintenance rate based on Reference Example 1-1 improves with a decrease in the content of sulfur dioxide, and Reference Example 1-1 and It was confirmed that the same 60 ° C. high temperature cycle characteristics were exhibited. In particular, in the region where the content of sulfur dioxide is 2.0% by mass or less, it was confirmed that the discharge capacity retention rate based on Reference Example 1-1 was a more excellent value. Further, as the sulfur dioxide content decreases from 2.0% by mass or less to 0.5% by mass or less, and further from 0.5% by mass or less to less than 0.01% by mass, the discharge capacity is maintained to a slight extent. The rate has been improved.
From these results, the sulfur dioxide content is preferably 2.5% by mass or less, more preferably 2.0% by mass or less, still more preferably 0.5% by mass or less, and particularly preferably 0.01% by mass. It is less than mass%.

[Examples 2-1 to 2-15, Comparative examples 2-1 to 2-5, Reference examples 2-1 to 2-5]
As shown in Table 3, a nonaqueous electrolyte battery was produced and evaluated in the same manner as in Example 1-1 except that a positive electrode, a negative electrode, and a test solution were used in combination. The results are shown in Table 3 and FIG.

When the non-aqueous electrolyte is changed from the EC / EMC system (Table 2) to the EC / DMC / PE system (basic composition non-aqueous electrolyte B system) with the positive electrode NCM and the negative electrode graphite as they are, (III) It is confirmed that the discharge capacity retention rate is significantly improved by reducing the sulfur dioxide content contained in the slag to 2.5% by mass or less, and is equal to or higher than the system using MMDS (Reference Example 2-1). It was done. In particular, when the content of sulfur dioxide is 2.0% by mass or less, it is confirmed that the discharge capacity retention rate exceeds Reference Example 2-1, and the smaller the sulfur dioxide content, the better the discharge capacity. The tendency to obtain the maintenance rate was confirmed.
Similarly, in the case of using a non-aqueous electrolyte containing not only LiPF ₆ but also LiFSI as a solute (basic composition non-aqueous electrolyte C), the sulfur dioxide content is reduced to 2.5% by mass or less. It is confirmed that the discharge capacity retention rate is greatly improved by reducing the amount, and it is confirmed that the discharge capacity maintenance rate exceeds the system using MMDS (Reference Example 2-2). As in the above, the lower the sulfur dioxide content, the better. A tendency to obtain a discharge capacity maintenance rate was confirmed.

Even when the positive electrode is changed from NCM to LCO or LFP, the discharge capacity retention rate is reduced to 2.5% by mass or less by using MMDS (respectively reference examples 2-3, It was confirmed that the value was the same as that of Reference Example 2-4), and, similarly to the above, it was confirmed that the smaller the content of sulfur dioxide, the better the discharge capacity retention rate.
In addition, when the non-aqueous electrolyte is changed to EC / EMC / FEC (basic composition non-aqueous electrolyte D) and the negative electrode is changed from graphite to silicon, the content of sulfur dioxide is 2.5. By reducing to less than mass%, it was confirmed that the value was the same as the system using MMDS (Reference Example 2-5), and as described above, the smaller the sulfur dioxide content, the better. A tendency to obtain a discharge capacity maintenance rate was confirmed.

  From the above results, regardless of the type of positive and negative electrodes, non-aqueous solvent, and type (III), the content of sulfur dioxide contained in (III) is reduced to 2.5% by mass or less, It is possible to greatly improve the discharge capacity maintenance rate and to be comparable to the discharge capacity maintenance rate of the corresponding system using MMDS instead of (III).

As is apparent from FIG. 2, the sulfur dioxide content and the discharge capacity retention ratio are not proportional.
In the region where the sulfur dioxide content exceeds 2.5% by mass, the discharge capacity maintenance rate based on the system using MMDS (corresponding reference examples) greatly decreases as the sulfur dioxide content increases. Yes.
On the other hand, in the region where the sulfur dioxide content is 2.5% by mass or less, the discharge capacity maintenance rate based on the corresponding reference examples is improved with the decrease in the sulfur dioxide content, and the corresponding reference It was confirmed that the same high-temperature cycle characteristics at 60 ° C. as in the examples were exhibited. In particular, it was confirmed that in the region where the content of sulfur dioxide is 2.0% by mass or less, the discharge capacity retention rate based on each corresponding reference example becomes a more excellent value. Further, as the sulfur dioxide content decreases from 2.0% by mass or less to 0.5% by mass or less, and further from 0.5% by mass or less to less than 0.01% by mass, the discharge capacity is maintained to a slight extent. The rate has been improved.
From these results, the sulfur dioxide content is preferably 2.5% by mass or less, more preferably 2.0% by mass or less, still more preferably 0.5% by mass or less, and particularly preferably 0.01% by mass. It is less than mass%.

[Examples 3-1 to 3-8, Reference examples 3-1 to 3-8]
As shown in Table 4, a nonaqueous electrolyte battery was produced and evaluated in the same manner as in Example 1-3, except that the electrolyte component contained other component (IV). The results are shown in Table 4.
In Example 3-1 and Reference Example 3-1, VC was added so that the concentration became 2.0 mass%.
Moreover, in Example 3-2 and Reference Example 3-2, LBOB was added so that the concentration was 1.0 mass%.
In Example 3-3 and Reference Example 3-3, LDFBOP was added so that the concentration was 1.0 mass%.
Moreover, in Example 3-4 and Reference Example 3-4, LTOP was added so that the concentration was 1.0 mass%.
Moreover, in Example 3-5 and Reference Example 3-5, LDFP was added so that the concentration was 1.0 mass%.
In Example 3-6 and Reference Example 3-6, LBDFA was added so that the concentration was 1.0 mass%.
Moreover, in Example 3-7 and Reference Example 3-7, TVSI was added so that the concentration was 0.5 mass%.
Moreover, in Example 3-8 and Reference Example 3-8, SUN was added so that the concentration was 1.0 mass%.

  As shown in Table 4, when any other component (IV) is added, the discharge capacity retention rate is reduced by reducing the content of sulfur dioxide contained in (III) to 2.5% by mass or less. Can be made equivalent to the discharge capacity maintenance rate of the system containing MMDS instead of (III) and containing the corresponding (IV). Moreover, it turns out that the said discharge capacity maintenance factor is improving the said Examples 3-1 to 3-8 compared with Example 1-3 using the test liquid which has not added the other component (IV). Among them, the effects of LBOB (Example 3-2), LDFBOP (Example 3-3), LTOP (Example 3-4), and TVSI (Example 3-7) were particularly excellent.

  From the above results, it is possible to further improve the discharge capacity maintenance rate by adding the other component (IV) together with (III) in which the content of sulfur dioxide is reduced to 2.5% by mass or less. is there.

Claims (12)

(I) a non-aqueous organic solvent,
(II) a solute that is an ionic salt,
(III) An electrolyte for a non-aqueous electrolyte battery comprising a cyclic sulfonic anhydride derivative having two sulfonyl groups represented by the general formula (1),
The cyclic sulfonic anhydride derivative is
Starting from sulfur trioxide and a compound containing a double bond,
The content of sulfur dioxide, which is an impurity derived from the reaction between the sulfur trioxide and a compound containing a double bond, is 2.5% by mass or less.
Non-aqueous electrolyte battery electrolyte.

[In the general formula (1), R ¹ , R ² , R ³ and R ⁴ are each independently hydrogen, alkyl group, alkoxy group, alkenyl group, alkenyloxy group, alkynyl group, alkynyloxy group, aryl group. And a group selected from the group consisting of aryloxy groups, and these groups may have a fluorine atom, a chlorine atom, or an oxygen atom. In the case where a direct bond is formed between C ^{1 and} R ¹ or between C ^{2 and} R ² , R ³ and R ⁴ do not exist, respectively. Further, as shown in the following (2) and (4), a double bond may be directly formed between C ^{1 and} C ² . In this case, R ³ and R ⁴ do not exist. Further, as shown in (3) and (4), R ¹ and R ² may take the form of being included in the same ring structure. ]

The electrolyte solution for nonaqueous electrolyte batteries according to claim 1, wherein the sulfur dioxide content is 2.0 mass% or less. The cyclic sulfonic anhydride derivative having two sulfonyl groups represented by the general formula (1) is represented by the following compound No. The electrolyte solution for nonaqueous electrolyte batteries according to claim 1 or 2, wherein the electrolyte solution is at least one selected from the group consisting of 1 to 24.

The nonaqueous electrolyte battery according to any one of claims 1 to 3, wherein the concentration of (III) with respect to the total amount of (I) and (II) is 0.01% by mass or more and 10.0% by mass or less. Electrolyte. The electrolyte solution for nonaqueous electrolyte batteries according to any one of claims 1 to 3, wherein the concentration is 0.05% by mass or more and 5.0% by mass or less. The ionic salt as the solute is at least one cation selected from the group consisting of lithium and sodium;
Hexafluorophosphate anion, tetrafluoroborate anion, difluorooxalatoborate anion, tetrafluorooxalatophosphate anion, trifluoromethanesulfonate anion, fluorosulfonate anion, bis (trifluoromethanesulfonyl) imide anion, bis (fluoro (Sulfonyl) imide anion, (trifluoromethanesulfonyl) (fluorosulfonyl) imide anion, bis (difluorophosphonyl) imide anion, (difluorophosphonyl) (fluorosulfonyl) imide anion, and (difluorophosphonyl) (trifluorosulfonyl) imide The electrolysis for a non-aqueous electrolyte battery according to any one of claims 1 to 5, which is an ionic salt comprising a pair of at least one anion selected from the group consisting of anions. . The non-aqueous organic solvent is ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, methyl butyl carbonate, ethylene carbonate, propylene carbonate, butylene carbonate, fluoroethylene carbonate, methyl acetate, ethyl acetate, propionic acid Methyl, ethyl propionate, methyl 2-fluoropropionate, ethyl 2-fluoropropionate, diethyl ether, acetonitrile, propionitrile, tetrahydrofuran, 2-methyltetrahydrofuran, furan, tetrahydropyran, 1,3-dioxane, 1,4 -Dioxane, dibutyl ether, diisopropyl ether, 1,2-dimethoxyethane, N, N-dimethylformamide, Methyl sulfoxide, sulfolane, .gamma.-butyrolactone, and .gamma. is at least one valerolactone consisting lactone selected from the group, the non-aqueous electrolyte battery electrolyte solution according to any one of claims 1 to 6. The electrolyte solution for a nonaqueous electrolyte battery according to any one of claims 1 to 6, wherein the nonaqueous organic solvent contains at least one selected from the group consisting of cyclic carbonates, chain carbonates, and esters. The cyclic carbonate is at least one selected from the group consisting of ethylene carbonate, propylene carbonate, and butylene carbonate, and the chain carbonate is ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, And at least one selected from the group consisting of methyl butyl carbonate, and the ester comprises methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, methyl 2-fluoropropionate, and ethyl 2-fluoropropionate The electrolyte solution for a non-aqueous electrolyte battery according to claim 8, which is at least one selected from the group. further,
(IV) Other components include cyclohexylbenzene, cyclohexylfluorobenzene, biphenyl, difluoroanisole, t-butylbenzene, t-amylbenzene, 2-fluorotoluene, 2-fluorobiphenyl, vinylene carbonate, dimethyl vinylene carbonate, vinyl ethylene carbonate, fluoro Ethylene carbonate, difluoroethylene carbonate, ethynyl ethylene carbonate, divinyl ethylene carbonate, methyl difluoro vinyl silane, methyl fluoro divinyl silane, dimethyl divinyl silane, methyl trivinyl silane, tetra vinyl silane, maleic anhydride, succinic anhydride, succinonitrile, bisoxalato boron Lithium acid, sodium bisoxalatoborate, potassium bisoxalatoborate , Lithium difluorooxalatoborate, sodium difluorooxalatoborate, potassium difluorooxalatoborate, lithium tetrafluorooxalate, sodium tetrafluorooxalate, potassium tetrafluorooxalate, difluorobis (oxalato ) Lithium phosphate, sodium difluorobis (oxalato) phosphate, potassium difluorobis (oxalato) phosphate, lithium tris (oxalato) phosphate, sodium tris (oxalato) phosphate, potassium tris (oxalato) phosphate, difluorophosphate Lithium, lithium monofluorophosphate, lithium bis (trifluoromethanesulfonyl) imide, sodium bis (trifluoromethanesulfonyl) imide, bis (trifluoromethanes Phosphonyl) imide potassium, bis (fluorosulfonyl) imide lithium, bis (fluorosulfonyl) imide sodium, bis (fluorosulfonyl) imide potassium, (trifluoromethanesulfonyl) (fluorosulfonyl) imide lithium, (trifluoromethanesulfonyl) (fluorosulfonyl) Sodium imido, (trifluoromethanesulfonyl) (fluorosulfonyl) imide potassium, bis (difluorophosphonyl) imide lithium, bis (difluorophosphonyl) imide sodium, bis (difluorophosphonyl) imide potassium, (difluorophosphonyl) (fluorosulfonyl) ) Imidolithium, (difluorophosphonyl) (fluorosulfonyl) imido sodium, (difluorophosphonyl) (fluorosulphonyl) And (difluorophosphonyl) (trifluorosulfonyl) imide lithium, (difluorophosphonyl) (trifluorosulfonyl) imide sodium, and (difluorophosphonyl) (trifluorosulfonyl) imide potassium. The electrolyte solution for nonaqueous electrolyte batteries according to claim 1, comprising at least one kind. (IV) is vinylene carbonate, vinyl ethylene carbonate, fluoroethylene carbonate, dimethyldivinylsilane, methyltrivinylsilane, tetravinylsilane, lithium bisoxalate borate, lithium difluorooxalate borate, lithium tetrafluorooxalate triphosphate, difluoro Lithium bis (oxalato) phosphate, lithium tris (oxalato) phosphate, lithium difluorophosphate, lithium monofluorophosphate, lithium bis (trifluoromethanesulfonyl) imide, lithium bis (fluorosulfonyl) imide, bis (difluorophosphonyl) It is at least 1 sort (s) selected from the group which consists of) imido lithium and (difluorophosphonyl) (fluorosulfonyl) imide lithium. Non-aqueous electrolyte battery electrolyte solution. A positive electrode;
A negative electrode made of lithium or a negative electrode material capable of occluding and releasing lithium, or a negative electrode made of negative electrode material capable of occluding and releasing sodium or sodium;
A non-aqueous electrolyte battery comprising the non-aqueous electrolyte battery electrolyte according to claim 1.

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