Composition, electrolyte material, and electrolyte

Abstract

To provide a composition, which is a composition containing a sulfonyl imide salt, which has superior storage stability even at a high temperature, and which can be used for a liquid electrolyte material and a liquid electrolyte.SOLUTION: A composition comprises an electrolyte, a solvent, and an anion component. The electrolyte contains a sulfonyl imide salt. The anion component contains an acid component having an acid dissociation constant pKa of 0 or more and 6.5 or less (as to acid ionizing more than once, an acid dissociation constant pKa1 of the first stage), of which the concentration is 50 ppm or more and 10000 ppm or less to the electrolyte. In the composition, the concentration of fluoride ions is 100 ppm or less to the electrolyte; and the concentration of sulfate ions is 100 ppm or less to the electrolyte.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to compositions, electrolyte materials, and electrolytes. [Background technology]

[0002] Various electrolyte materials and compositions that can be used for electrolytes, etc. have been studied. For example, the present applicant has proposed an electrolyte material that contains a fluorosulfonylimide salt and an electrolyte solvent, in which the concentration of the fluorosulfonylimide salt contained in the electrolyte material is 30 mass % or more, and the amount of the solvent used to produce the fluorosulfonylimide salt remaining in the electrolyte material is 3000 ppm or less (Patent Document 1).

[0003] The applicant has also disclosed in the specification of Japanese Patent Application No. 2019-103361 a composition comprising an electrolyte and a solvent, wherein the electrolyte comprises a fluorosulfonylimide salt, the solvent comprises an organic solvent having a dielectric constant of 10 or less, and further comprises an amidosulfuric acid component. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-083204 Summary of the Invention [Problem to be solved by the invention]

[0005] Liquid sulfonylimide salts containing a sulfonylimide salt, such as a fluorosulfonylimide salt, and a solvent are easier to handle than powdered sulfonylimide salts, but they suffer from the problem of decomposition reactions of the sulfonylimide salt progressing during storage, resulting in poor storage stability (the property of suppressing decomposition reactions of the sulfonylimide salt even during long-term storage). To address this issue, the electrolyte solution material described in Patent Document 1 and the composition disclosed in Japanese Patent Application No. 2019-103361 have improved storage stability at room temperature (e.g., 25°C). However, there is a demand for liquid sulfonylimide salts that can be stored for long periods of time, not only at room temperature but also at high temperatures (e.g., 40°C or higher) where decomposition of the sulfonylimide salt is accelerated.

[0006] The present disclosure has been made in view of the above points, and an object of the present disclosure is to provide a composition containing a sulfonylimide salt, which has excellent storage stability even at high temperatures and can be used as an electrolyte material or an electrolyte. [Means for solving the problem]

[0007] As a result of extensive research into solving the above-mentioned problems, the present inventors have found that the above-mentioned problems can be solved by including, as an anion component, an acid component having a dissociation constant pKa within a predetermined range at a predetermined concentration.

[0008] The composition of the present disclosure includes an electrolyte, a solvent, and an anion component, wherein the electrolyte includes a sulfonylimide salt, and the anion component includes an acid component having an acid dissociation constant pKa (for a multiply ionizable acid, the first stage acid dissociation constant pKa1) of 0 to 6.5 in a concentration of 50 ppm to 10,000 ppm relative to the electrolyte, and the concentration of fluoride ions is 100 ppm or less, and the concentration of sulfate ions is 100 ppm or less, relative to the electrolyte.

[0009] The electrolyte material of the present disclosure is characterized by containing the composition.

[0010] The electrolyte solution of the present disclosure is prepared using the electrolyte solution material. [Effects of the Invention]

[0011] According to the present disclosure, it is possible to provide a composition containing a sulfonylimide salt that has excellent storage stability even at high temperatures and can be used as an electrolyte material or an electrolyte. DETAILED DESCRIPTION OF THE INVENTION

[0012]

[0023] The following detailed description of preferred embodiments of the present disclosure is merely exemplary in nature and is in no way intended to limit the present disclosure, its application, or its uses.

[0013] <Composition> The composition according to the present embodiment includes an electrolyte, a solvent, and an anion component. This composition can be suitably used, for example, as an electrolyte solution. In electrolyte solution applications, the composition may constitute at least a part of the electrolyte solution. For example, the composition may be used as an electrolyte solution material as it is, or may be used as the electrolyte solution.

[0014] (electrolyte) The composition of the present embodiment contains a sulfonylimide salt as an electrolyte. The sulfonylimide salt is a salt of a sulfonylimide anion and a sulfonylimide cation.

[0015] Examples of the sulfonylimide anion (sulfonylimide ion) include anions represented by the following formula (1).

[0016] [ka]

[0017] (In formula (1), X 1 and X 2 are the same or different (independently of each other) and represent F (fluorine atom) or a fluoroalkyl group having 1 to 6 carbon atoms.) In formula (1), examples of the fluoroalkyl group having 1 to 6 carbon atoms include alkyl groups having 1 to 6 carbon atoms in which some or all of the hydrogen atoms have been substituted with fluorine atoms. Specific examples of the fluoroalkyl group having 1 to 6 carbon atoms include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a fluoroethyl group, a difluoroethyl group, a trifluoroethyl group, and a pentafluoroethyl group. Substituent X 1 and X 2 Of these, a fluorine atom, a trifluoromethyl group, and a pentafluoroethyl group are preferred, a fluorine atom and a trifluoromethyl group are more preferred, and a fluorine atom is even more preferred.

[0018] Examples of the cation include metal cations (metal ions) [alkali metal cations (lithium cation, sodium cation, potassium cation, rubidium cation, cesium cation, etc.), alkaline earth metal cations (beryllium cation, magnesium cation, calcium cation, strontium cation, barium cation, etc.), aluminum cation, etc.]; ammonium cations (quaternary ammonium cations such as tetraethylammonium cation and triethylmethylammonium cation, etc.); phosphonium cations (quaternary phosphonium cations such as tetramethylphosphonium cation, etc.); etc. The type of cation may be appropriately selected depending on the application of the composition, etc. Among the cations, lithium cations (lithium ions) are preferred from the viewpoint of application to lithium ion batteries.

[0019] Among the sulfonylimide salts, from the viewpoint of improving the battery characteristics of a lithium ion battery, a salt of a sulfonylimide anion represented by the formula (1) and an alkali metal cation is preferred, and a salt of a sulfonylimide anion represented by the formula (1) and a lithium cation is more preferred.

[0020] Specific examples of sulfonylimide salts include bis(fluorosulfonyl)imide salts [e.g., lithium bis(fluorosulfonyl)imide, sodium bis(fluorosulfonyl)imide, potassium bis(fluorosulfonyl)imide, etc.]; bis(trifluoroalkylsulfonyl)imide salts such as bis(trifluoromethanesulfonyl)imide salts [e.g., lithium bis(trifluoromethanesulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, potassium bis(trifluoromethanesulfonyl)imide, etc.]; and bis(fluoro C) salts such as bis(pentafluoroethylsulfonyl)imide. 1-6 (Fluorosulfonyl)(fluoroalkylsulfonyl)imide salts such as (fluorosulfonyl)(trifluoromethanesulfonyl)imide salts; (fluorosulfonyl)(fluoroalkylsulfonyl)imide salts such as (fluorosulfonyl)(trifluoromethanesulfonyl)imide salts; (fluorosulfonyl)(pentafluoroethylsulfonyl)imide salts; (fluorosulfonyl)(fluoro C such as (fluorosulfonyl)(heptafluoropropylsulfonyl)imide 1-6 Alkyl sulfonyl)imide salts [preferably (fluorosulfonyl)(perfluoro C 1-6 and the like. The sulfonylimide salts may be used alone or in combination of two or more. Among the sulfonylimide salts, from the viewpoint of battery characteristics (cycle characteristics, rate characteristics, low-temperature characteristics, etc.), bis(fluorosulfonyl)imide salts and bis(trifluoromethanesulfonyl)imide salts are preferred, lithium bis(fluorosulfonyl)imide and lithium bis(trifluoromethanesulfonyl)imide are more preferred, and lithium bis(fluorosulfonyl)imide is even more preferred.

[0021] The sulfonylimide salt may be a commercially available product or may be prepared by manufacturing. Examples of methods for manufacturing a sulfonylimide salt include a method of dissolving a bis(fluorosulfonyl)imide salt such as powdered lithium bis(fluorosulfonyl)imide in a solvent described below to manufacture a lithium bis(fluorosulfonyl)imide solution; a method of reacting a mixture containing bis(fluorosulfonyl)imide and an alkali metal compound in water to prepare an aqueous solution of bis(fluorosulfonyl)imide alkali metal salt, and then removing the water by a volatilization operation using a carbonate solvent described below to manufacture a bis(fluorosulfonyl)imide alkali metal salt solution; and a method of reacting a mixture containing bis(fluorosulfonyl)imide and an alkali metal compound in the solvent to manufacture a bis(fluorosulfonyl)imide alkali metal salt solution.

[0022] Bis(fluorosulfonyl)imide can be synthesized by a known method. For example, a method of synthesizing bis(fluorosulfonyl)imide from a bis(halogenated sulfonyl)imide using a fluorinating agent can be mentioned. Examples of halogens in bis(halogenated sulfonyl)imide include Cl, Br, I, and At, in addition to F.

[0023] The fluorination step of synthesizing a bis(fluorosulfonyl)imide from a bis(halogenated sulfonyl)imide using a fluorinating agent is described below. In the fluorination step, a fluorination reaction of the bis(halogenated sulfonyl)imide is carried out. Examples include the method described in CA2527802 and the method described in Jean'ne M. Shreeve et al., Inorg. Chem. 1998, 37 (24), 6295-6303. The bis(halogenated sulfonyl)imide used as the starting material may be commercially available or may be synthesized by a known method. Another method is described in JP-A-8-511274, in which a bis(fluorosulfonyl)imide is synthesized using urea and fluorosulfonic acid.

[0024] Examples of alkali metal compounds include oxides such as LiO, NaO, KO, RbO, and CsO; hydroxides such as LiOH, NaOH, KOH, RbOH, and CsOH; carbonates such as LiCO3, NaCO3, KCO3, RbCO3, and CsCO3, and hydrogencarbonates such as LiHCO3, NaHCO3, KHCO3, RbHCO3, and CsHCO3; chlorides such as LiCl, NaCl, KCl, RbCl, and CsCl; fluorides such as LiF, NaF, KF, RbF, and CsF; alkoxide compounds such as CHOLi and EtOLi; and alkyllithium compounds such as EtLi, BuLi, and t-BuLi (where Et represents an ethyl group and Bu represents a butyl group).

[0025] The content of the sulfonylimide salt (preferably lithium bis(fluorosulfonyl)imide) (the total content when two or more types are used) is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and even more preferably 35% by mass or more, relative to the total amount of the components contained in the composition (100% by mass), from the viewpoint of being applicable to a wide range of electrolyte compositions when the composition is used as an electrolyte material. Furthermore, from the viewpoint of improving the storage stability of the composition even at high temperatures, the content is preferably 60% by mass or less, more preferably 55% by mass or less, and even more preferably 50% by mass or less, relative to the total amount of the composition.

[0026] The composition of this embodiment may also contain other electrolyte salts different from the sulfonylimide salts, such as alkali metal salts of fluorosulfonic acid (e.g., LiFSO3), alkali metal salts of trifluoromethanesulfonic acid (e.g., LiCF3SO3), alkali metal salts of perfluoroalkanesulfonylmethides (e.g., LiC(CF3SO2)3), and LiPF a (C m F 2m+1 ) 6-a Fluorophosphates such as (0≦a≦6, 1≦m≦4); alkali metal perchlorates such as LiClO4; LiBF b (C n F 2n+1 ) 4-b(0≦b≦4, 1≦n≦4), alkali metal salts of oxalatoborates such as LiBOB, cyanoborates such as lithium tetracyanoborate, LiAsF, LiI, LiSbF, etc. The other electrolyte salts may be used alone or in combination of two or more.

[0027] (solvent) The composition of the present embodiment contains a solvent and can also be called a solvent composition. In the solvent composition, the sulfonylimide salt and / or the anion component described below may be present (contained) in the form of ions or may be dissolved.

[0028] The solvent can be appropriately selected depending on the intended use of the composition (solvent composition), and may be any aprotic solvent in which the sulfonylimide salt can be dissolved.

[0029] Examples of the solvent include carbonate solvents, chain ethers, cyclic ethers, chain esters, cyclic esters, alkyl phosphate esters, aliphatic nitriles, aromatic nitriles, sulfones, sulfolanes, nitromethane, 1,3-dimethyl-2-imidazolidinone, 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone, 3-methyl-2-oxazolidinone, etc. These solvents may be used alone or in combination of two or more.

[0030] Examples of carbonate solvents include linear carbonate solvents, saturated cyclic carbonates, unsaturated cyclic carbonates, and fluorine-containing cyclic carbonates. Examples of linear carbonate solvents include dialkyl carbonates having 1 to 4 carbon atoms, such as dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC); alkylaryl carbonates having 1 to 4 carbon atoms, such as methyl phenyl carbonate; and diaryl carbonates, such as diphenyl carbonate. Examples of saturated cyclic carbonates include alkylene carbonates having 2 to 6 carbon atoms, such as ethylene carbonate, propylene carbonate, 2,3-dimethyl ethylene carbonate, and 1,2-butylene carbonate; and erythritol carbonate. Examples of unsaturated cyclic carbonates include alkenylene carbonates, such as vinylene carbonate, methyl vinylene carbonate, and ethyl vinylene carbonate; and 2-vinyl ethylene carbonate. Examples of fluorine-containing cyclic carbonates include fluoroethylene carbonate, 4,5-difluoroethylene carbonate, and trifluoropropylene carbonate.

[0031] Examples of the chain ethers include alkanediol dialkyl ethers such as ethylene glycol dimethyl ether and ethylene glycol diethyl ether; and polyalkanediol dialkyl ethers such as triethylene glycol dimethyl ether and tetraethylene glycol dimethyl ether.

[0032] Examples of cyclic ethers include tetrahydrofurans such as tetrahydrofuran, 2-methyltetrahydrofuran, and 2,6-dimethyltetrahydrofuran; tetrahydropyrans such as tetrahydropyran; dioxanes such as 1,4-dioxane; dioxolanes such as 1,3-dioxolane; crown ethers, and the like.

[0033] Examples of the chain esters include aliphatic carboxylic acid esters such as ethyl acetate, isopropyl acetate, butyl acetate, ethyl propionate, and propyl propionate; and aromatic carboxylic acid esters such as methyl benzoate and ethyl benzoate.

[0034] Examples of cyclic esters (or lactones) include esters (carboxylic acid esters) of γ-butyrolactone, γ-valerolactone, δ-valerolactone, and the like.

[0035] Examples of the alkyl phosphate include phosphates such as trimethyl phosphate, ethyl dimethyl phosphate, diethyl methyl phosphate, and triethyl phosphate.

[0036] Examples of aliphatic nitriles include acetonitrile, propionitrile, methoxypropionitrile, glutaronitrile, adiponitrile, 2-methylglutaronitrile, valeronitrile, butyronitrile, and isobutyronitrile.

[0037] Examples of aromatic nitriles include benzonitrile and tolunitrile.

[0038] Examples of sulfones include dimethyl sulfone, ethyl methyl sulfone, and diethyl sulfone.

[0039] Examples of sulfolanes include sulfur-containing solvents such as sulfolane, 3-methylsulfolane, and 2,4-dimethylsulfolane.

[0040] Among the solvents, from the viewpoint of improving the storage stability of the composition even at high temperatures, carbonate solvents are preferred, chain carbonate solvents are more preferred, dialkyl carbonates having 1 to 4 carbon atoms are even more preferred, dimethyl carbonate (DMC) and ethyl methyl carbonate (EMC) are even more preferred, and dimethyl carbonate (DMC) is even more preferred.

[0041] More specifically, the solvent preferably contains a carbonate solvent, more preferably contains a chain carbonate solvent, and even if the concentration of the anion component is relatively low (for example, a concentration of 50 ppm or more and 1000 ppm or less relative to the electrolyte), from the viewpoint of improving the storage stability of the composition at high temperatures, it is further preferable that the carbonate solvent is a chain carbonate solvent (in other words, the carbonate solvent consists solely of a chain carbonate solvent), and it is particularly preferable that the solvent consists solely of a chain carbonate solvent.

[0042] The proportion of carbonate solvent (preferably chain carbonate solvent) relative to the total solvent is not particularly limited, and may be 10% by volume or more, 20% by volume or more, 30% by volume or more, 40% by volume or more, 50% by volume or more, 60% by volume or more, 70% by volume or more, 80% by volume or more, 90% by volume or more, 95% by volume or more, 99% by volume or more, or 100% by volume (substantially carbonate solvent only (preferably substantially chain carbonate solvent only)).

[0043] When the solvent composition is used as an electrolyte material, for example, the solvent composition may be further mixed with a solvent (the solvent composition may be further diluted with a solvent) to form an electrolyte. Examples of the solvent to be mixed with the solvent composition include the carbonate solvents and other solvents. The solvent to be mixed with the solvent composition may be the same as or different from the solvent constituting the solvent composition.

[0044] (anionic component) The composition of this embodiment contains, as an anion component, an acid component (hereinafter also referred to as a "specific acid component") having an acid dissociation constant pKa (for a multiply ionizable acid, the first stage acid dissociation constant pKa1) (temperature: room temperature (25°C), solvent: water) of 0 to 6.5. This allows the composition to exhibit excellent storage stability at room temperature. In particular, the composition exhibits excellent long-term storage stability (more than two months) even at high temperatures (e.g., 40°C or higher). In this specification, the anion component refers to a partial structure (in the above example, an amidosulfate ion) of a specific acid component, such as a specific acid (e.g., amidosulfate, as described below) or a salt thereof (e.g., lithium amidosulfate, as described below) that can become an anion upon ion dissociation in a solution (solvent composition).

[0045] The specific acid component has a pKa (pKa1) greater than that of a sulfuric acid component (pKa1 = -3) generated by decomposition of the sulfonylimide salt. Examples of the specific acid component include an amidosulfuric acid component (pKa1 = 1), an acetic acid component (pKa1 = 4.8), a carbonic acid component (pKa1 = 6.1), and a phosphoric acid component (pKa1 = 1.8). The specific acid component may be contained alone or in combination of two or more. The structure of the specific acid component in the (solvent) composition is not particularly limited, and the specific acid component may be present (contained) in the form of an ion (not necessarily dissolved), or may be dissolved.

[0046] Examples of the amidosulfuric acid component (amidosulfuric acid compound, amidosulfuric acid-based compound, amidosulfuric acid analogues) include amidosulfuric acid (sulfamic acid), amidosulfuric acid derivatives, and salts thereof.

[0047] The structure of the amidosulfuric acid component is not particularly limited, and may be, for example, a neutral type (H2NSO2(OH), HN=SO(OH)2, etc.), a zwitterionic type (H3N + SO3 - , H2N + =SO(OH)O - etc.), or a structure including any of these.

[0048] Amidosulfuric acid derivatives include N-substituted amidosulfuric acids (N-substituted sulfamic acids, etc.).

[0049] Such amidosulfonic acid derivatives (and salts thereof) may be compounds (N-substituted amidosulfonic acid and salts thereof) represented by the following formula (2). The following formula (2) is a compound represented by the neutral type (R 1 R 2 NSO2(OM)), but may also be in the zwitterionic form, and may contain both.

[0050] [ka]

[0051] (In formula (2), R 1 , R 2 represents H (hydrogen atom), a hydroxyl group, or an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aryl group having 6 to 16 carbon atoms, an aralkyl group having 7 to 16 carbon atoms, or an alkanoyl group having 2 to 16 carbon atoms, which may have a heteroatom; R 1 and R 2 may form a ring structure. 1 , R 2 When R is the above group other than H, they may be the same or different (R 1 , R 2 are not identical when H (R 1 and R 2 is not H at the same time. M represents H (hydrogen atom) or a metal atom. In formula (2), examples of alkyl groups having 1 to 10 carbon atoms include a methyl group, etc. Examples of cycloalkyl groups having 3 to 10 carbon atoms include a cyclopropyl group, etc. Examples of aryl groups having 6 to 16 carbon atoms include a phenyl group and a naphthyl group, etc. Examples of aralkyl groups having 7 to 16 carbon atoms include a benzyl group and a phenethyl group, etc. Examples of alkanoyl groups having 2 to 16 carbon atoms include a benzoyl group, etc.

[0052] These may be groups containing heteroatoms (nitrogen atoms, oxygen atoms, sulfur atoms, phosphorus atoms, etc.), and examples of such groups include groups in which some of the carbon atoms are substituted with heteroatoms, and thiocycloalkyl groups (groups corresponding to thiocycloalkanes such as thiepane, thiocane, thietane, thiane, and dithiane).

[0053] Furthermore, examples of substituents that may be substituted on these groups include, but are not limited to, a hydroxyl group, a halogen atom, an amino group, a carboxyl group, an alkoxy group, an acyl group, etc. These may be substituted alone or in combination of two or more.

[0054] Examples of the metal atom include alkali metal atoms such as lithium, sodium, and potassium; alkaline earth metal atoms such as magnesium, calcium, and barium; and aluminum.

[0055] Specific amidosulfuric acid derivatives and salts thereof [N-substituted amidosulfuric acid and salts thereof (or compounds represented by the formula (2))] include N-hydroxy amidosulfuric acid; N-mono- or dialkyl amidosulfuric acid [N-methyl amidosulfuric acid, N-ethyl amidosulfuric acid, N-(1-methylpropyl) amidosulfuric acid, N-(2-methylbutyl) amidosulfuric acid, N-(2,2-dimethylpropyl) amidosulfuric acid, N,N-diethyl amidosulfuric acid, N-(3-hydroxypropyl) amidosulfuric acid, N-methyl-N-(2,3-dihydro ... N-(2-hydroxypropyl)amidosulfuric acid, N,N-bis(2-hydroxyethyl)amidosulfuric acid, N-(2,3-dihydroxypropyl)amidosulfuric acid, N-(3-methoxy-4-methylphenyl)amidosulfuric acid, N-methyl-N-(2-hydroxy-3-chloropropyl)amidosulfuric acid, N-(2-hydroxy-3-chloropropyl)amidosulfuric acid, N-ethyl-N-(2-hydroxy-3-chloropropyl)amidosulfuric acid, etc.; N-mono- or dicycloalkylamidosulfuric acid (N-cyclohexylamidosulfuric acid, N, N-Dicyclohexylamidosulfuric acid, etc.); N-Mono- or diarylamidosulfuric acid [N-phenylamidosulfuric acid, N-naphthylamidosulfuric acid, N-hydroxy-N-(2-hydroxy-1-naphthyl)amidosulfuric acid, N-(4-bromophenyl)amidosulfuric acid, etc.]; N-Mono- or diaralkylamidosulfuric acid [N-benzylamidosulfuric acid, N-(β-methylphenethyl)amidosulfuric acid, etc.]; N-Alkyl-N-arylamidosulfuric acid (N-ethyl-N-phenylamidosulfuric acid, etc.); N-Mono- or diacylamidosulfuric acid [ N-benzoylamidosulfuric acid, N-(3-chloroalanyl)amidosulfuric acid, N-(3-chloro-3-methylalanyl)amidosulfuric acid, etc.; N-thiocycloalkylamidosulfuric acid [N-(thiepan-4-yl)amidosulfuric acid, N-thiocan-4-ylamidosulfuric acid, thiocan-5-ylamidosulfuric acid, N-thietan-3-ylamidosulfuric acid, N-1,3-dithian-5-ylamidosulfuric acid, N-(thian-3-yl)amidosulfuric acid, N-(thiolan-3-yl)amidosulfuric acid, etc.]; and salts thereof. Amidosulfuric acid derivatives and salts thereof may be used either alone or in combination of two or more.

[0056] The salt of the amidosulfuric acid component is not particularly limited and may be, for example, a salt in which amidosulfuric acid or an amidosulfuric acid derivative is either a base or an acid, and typically may be a salt in which amidosulfuric acid or an amidosulfuric acid derivative is an acid (a salt of amidosulfuric acid or an amidosulfuric acid derivative and a base).

[0057] Specific examples of the salt include alkali metal salts such as lithium salt, sodium salt, and potassium salt; alkaline earth metal salts such as magnesium salt, calcium salt, and barium salt; and metal salts such as aluminum salt. Among these, alkali metal salts are preferred, and lithium salts are more preferred. The salt may also be a salt corresponding to the cation of the electrolyte to be combined. For example, when a lithium salt is used as the electrolyte, a lithium salt (such as lithium amidosulfate) may be used.

[0058] The amidosulfuric acid component may typically include at least one selected from amidosulfuric acid, amidosulfuric acid derivatives, and alkali metal salts thereof, particularly at least one selected from amidosulfuric acid and alkali metal amidosulfuric acid salts (e.g., lithium amidosulfate, etc.).

[0059] The carboxylic acid and its salt, which are typified by the acetic acid component, may be a compound represented by the following formula (3).

[0060] [C3] R 3 COOM (3) (In formula (3), R 3 represents H (hydrogen atom), an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aryl group having 6 to 16 carbon atoms, an aralkyl group having 7 to 16 carbon atoms, or an alkanoyl group having 2 to 16 carbon atoms, which may have a substituent, and may contain a heteroatom. M is the same as above. In formula (3), examples of alkyl groups having 1 to 10 carbon atoms include a methyl group, etc. Examples of cycloalkyl groups having 3 to 10 carbon atoms include a cyclopropyl group, etc. Examples of aryl groups having 6 to 16 carbon atoms include a phenyl group and a naphthyl group, etc. Examples of aralkyl groups having 7 to 16 carbon atoms include a benzyl group and a phenethyl group, etc. Examples of alkanoyl groups having 2 to 16 carbon atoms include a benzoyl group, etc.

[0061] These may be groups containing heteroatoms (nitrogen atoms, oxygen atoms, sulfur atoms, phosphorus atoms, etc.), and examples of such groups include groups in which some of the carbon atoms are substituted with heteroatoms, and thiocycloalkyl groups (groups corresponding to thiocycloalkanes such as thiepane, thiocane, thietane, thiane, and dithiane).

[0062] Furthermore, examples of substituents that may be substituted on these groups include, but are not limited to, a hydroxyl group, a halogen atom, an amino group, a carboxyl group, an alkoxy group, an acyl group, etc. These may be substituted alone or in combination of two or more.

[0063] Specific examples of carboxylic acids and salts thereof (or compounds represented by the formula (3)) include saturated fatty acids (formic acid, acetic acid, propionic acid, butyric acid, etc.), unsaturated fatty acids (linolenic acid, linoleic acid, oleic acid, etc.), hydroxy acids (lactic acid, citric acid, salicylic acid, etc.), dicarboxylic acids (oxalic acid, tartaric acid, phthalic acid, itaconic acid, maleic acid, etc.), amino acids (glycine, alanine, etc.), and salts thereof. The carboxylic acids and salts thereof may be used alone or in combination of two or more.

[0064] Specific examples of the salt include alkali metal salts (lithium salt, sodium salt, potassium salt, etc.), alkaline earth metal salts (magnesium salt, calcium salt, barium salt, etc.), and aluminum salts. Among these, alkali metal salts are preferred, and lithium salts are more preferred. The salt may also be a salt corresponding to the cation of the electrolyte to be combined. For example, when a lithium salt is used as the electrolyte, a lithium salt (lithium acetate, etc.) may be used.

[0065] The carbonic acid component is not particularly limited, and examples thereof include carbonates, hydrogen carbonates, etc. The carbonic acid components may be used alone or in combination of two or more kinds.

[0066] Specific examples of the salt include alkali metal salts (lithium salt, sodium salt, potassium salt, rubidium salt, cesium salt, etc.), alkaline earth metal salts (beryllium salt, magnesium salt, calcium salt, strontium salt, barium salt, etc.). Among these, alkali metal salts are preferred, and lithium salts are more preferred. The salt may also be a salt corresponding to the cation of the electrolyte to be combined. For example, when a lithium salt is used as the electrolyte, a lithium salt (lithium carbonate, etc.) may be used.

[0067] The phosphoric acid component is not particularly limited, and examples thereof include phosphate, hydrogen phosphate, dihydrogen phosphate, etc. The phosphoric acid components may be used alone or in combination of two or more kinds.

[0068] Specific examples of the salt include alkali metal salts (lithium salt, sodium salt, potassium salt, rubidium salt, cesium salt, etc.), alkaline earth metal salts (beryllium salt, magnesium salt, calcium salt, strontium salt, barium salt, etc.). Among these, alkali metal salts are preferred, and lithium salts are more preferred. The salt may also be a salt corresponding to the cation of the electrolyte to be combined. For example, when a lithium salt is used as the electrolyte, a lithium salt (lithium phosphate, etc.) may be used.

[0069] The composition of the present embodiment contains a specific acid component at a concentration of 50 ppm to 10,000 ppm relative to the electrolyte (sulfonylimide salt). Note that in this specification, "ppm" refers to "ppm by mass."

[0070] More specifically, from the viewpoint of improving the storage stability of the composition even at high temperatures, the concentration (ratio) of the specific acid component is 50 ppm or more, preferably 60 ppm or more, and 10,000 ppm or less, preferably 9,000 ppm or less, more preferably 8,000 ppm or less, even more preferably 7,000 ppm or less, and even more preferably 6,000 ppm or less. Note that when the carbonate solvent contained as a solvent is composed solely of a chain carbonate solvent, or when the solvent itself is composed solely of a chain carbonate solvent, the storage stability of the composition at high temperatures is improved even if the concentration of the specific acid component is relatively low. In this case, the upper limit of the concentration of the specific acid component is preferably 1,000 ppm or less, more preferably 500 ppm or less, and even more preferably 300 ppm or less.

[0071] When the specific acid component is a salt (a salt of an acid or a derivative thereof), the above ratio may be the ratio calculated as a non-salt form (or a free form, for example, an acid or an acid derivative). The salts of the above-mentioned acids or derivatives may be commercially available products or may be manufactured products.

[0072] As described above, the composition of the present embodiment is a solvent composition (solution) containing a sulfonylimide salt (electrolyte) and a solvent, and further containing a specific acid component (anion component) in a specific ratio. This is believed to not only exhibit excellent storage stability at low temperatures such as room temperature (e.g., 25°C) but also at high temperatures (e.g., 40°C or higher) where decomposition of the sulfonylimide salt is accelerated. For example, when the specific acid component is contained in the form of a salt, salt exchange is thought to occur between a strong acid component such as a sulfuric acid component generated by decomposition of the sulfonylimide salt and the salt of the specific acid component. As a result, the strong acid component precipitates as a salt (becoming an insoluble matter). On the other hand, the specific acid component generated by salt exchange has a higher pKa (pKa1) (i.e., weaker acidity) than the strong acid component, thereby suppressing or slowing the decomposition rate of the sulfonylimide salt caused by the specific acid component. More specifically, the strong acid component that accelerates the decomposition of the sulfonylimide salt forms a salt, thereby suppressing the acceleration of the decomposition of the sulfonylimide salt. Therefore, it is believed that the storage stability of the solvent composition is improved even at high temperatures because strong acid components such as sulfuric acid components generated by decomposition of the sulfonylimide salt are captured (trapped) by salts of specific acid components.

[0073] The specific acid component may be a component (additive) obtained by adding the above-mentioned specific acid or its salt to the solvent composition, or a component generated by decomposition of the sulfonylimide salt during synthesis of the sulfonylimide salt. As described above, this specific acid component may be present (contained) in the solvent composition in the form of an ion, or may be dissolved.

[0074] In the composition (solvent composition) of this embodiment configured as described above, decomposition of the sulfonylimide salt is suppressed, and as a result, the fluoride ion concentration is 100 ppm or less relative to the electrolyte, and the sulfate ion concentration is 100 ppm or less relative to the electrolyte. The concentrations of fluoride ions and sulfate ions in the solvent composition may be preferably 80 ppm or less, 60 ppm or less, 40 ppm or less, etc. Note that, from the viewpoint of improving storage stability even at high temperatures, the solvent composition may be substantially free of fluoride ions and / or sulfate ions (0 ppm). On the other hand, if the concentrations of fluoride ions and / or sulfate ions exceed 100 ppm relative to the electrolyte, the pH of the solvent composition decreases, which may result in accelerated decomposition of the sulfonylimide salt.

[0075] The composition (solvent composition) of this embodiment may contain water at a concentration of 0.1 ppm or more and 1000 ppm or less. The proportion of water in the solvent composition (solvent composition containing water) is preferably 0.1 ppm or more, more preferably 0.3 ppm or more, and may be 0.5 ppm or more, 0.7 ppm or more, 0.8 ppm or more, 1 ppm or more, 1.5 ppm or more, 2 ppm or more, 3 ppm or more, 5 ppm or more, 7 ppm or more, 10 ppm or more, etc. The upper limit of the proportion of water in the solvent composition is not particularly limited, and may be, for example, 3000 ppm, 1000 ppm, 900 ppm, 800 ppm, 700 ppm, 600 ppm, 500 ppm, 400 ppm, 300 ppm, 200 ppm, 100 ppm, 50 ppm, etc.

[0076] The composition (solvent composition) of this embodiment may contain other components (components other than the electrolyte, solvent, and anion component) as needed, provided that they are not harmful. The other components can be appropriately selected depending on the intended use of the solvent composition. For example, when the solvent composition is used as an electrolyte material or electrolyte, additives such as acid anhydrides (e.g., succinic anhydride, glutaric anhydride, maleic anhydride) for the purpose of improving or enhancing battery characteristics may be used. The other components may be used alone or in combination of two or more.

[0077] When the solvent composition contains other components, the proportion of the other components may be determined appropriately depending on the type, purpose, etc., and is, for example, 10% by mass or less, 8% by mass or less, 5% by mass or less, 3% by mass or less, etc.

[0078] The pH of the composition (solvent composition) of this embodiment can be appropriately selected depending on the type of electrolyte, etc., and is not particularly limited, but is preferably 5 or higher. More specifically, it is preferably 5 to 12, more preferably 5 to 11, and even more preferably 5 to 9. When the pH of the solvent composition is within the above range, decomposition of the constituent components (electrolytes) of the solvent composition and corrosion of the storage container for the solvent composition (and the accompanying generation of impurities) can be efficiently suppressed. Note that the above pH may be the pH at the time of preparation of the solvent composition, or the pH after a predetermined time has elapsed. By selecting a chain carbonate solvent, it is possible to efficiently suppress a decrease in pH over time, and as a result, the pH can be maintained within the above range for a long period of time.

[0079] <Electrolyte material> The electrolyte solution material according to this embodiment includes the composition according to this embodiment described above. That is, this electrolyte solution material is a solution (liquid) because it contains the electrolyte, solvent, and anion component described above. The liquid electrolyte solution material may contain only the composition (consisting only of the composition), or may further contain the electrolyte or solvent described above, and other components described above to the extent that they are not harmful. Note that all of the configurations applicable to the composition can be suitably applied to the electrolyte solution material.

[0080] <Electrolyte> The electrolyte solution according to this embodiment is prepared (made using) the electrolyte solution material according to this embodiment described above. This electrolyte solution may be prepared by using the electrolyte solution material as it is, or may be diluted by mixing the electrolyte solution material with the solvent described above. Note that all of the configurations applicable to the composition according to this embodiment described above can be suitably applied to the electrolyte solution. [Example]

[0081] The present disclosure will be described below based on examples. Note that the present disclosure is not limited to the following examples, and the following examples can be modified or changed based on the spirit of the present disclosure, and such modifications are not excluded from the scope of the present disclosure.

[0082] Synthesis Example 1 214 g of lithium carbonate and 600 g of butyl acetate were mixed, and then the resulting slurry was cooled in an ice bath. To this mixture, 1000 g of bis(fluorosulfonyl)imide (manufactured by Nippon Shokubai Co., Ltd.) was added dropwise over 45 minutes. Insoluble matter was removed from the resulting cloudy liquid using No. 5C Kiriyama filter paper, yielding a solution of lithium bis(fluorosulfonyl)imide (hereinafter referred to as "LiFSI") in butyl acetate.

[0083] 500 g of water was added to the solution obtained above and stirred at room temperature for 10 minutes. After stirring, the aqueous layer separated from the butyl acetate layer (organic layer) was removed to obtain an organic layer. 100 g of a 15% by mass aqueous solution of lithium hydroxide (LiOH) was added to this organic layer and stirred at room temperature for 10 minutes. After that, the aqueous layer was further removed from the reaction solution to obtain a butyl acetate solution of LiFSI.

[0084] Using a rotary evaporator ("REN-1000", manufactured by IWAKI Corporation), the reaction solvent was partially distilled off from the butyl acetate solution of LiFSI obtained in the extraction step under reduced pressure. The resulting insoluble matter was then filtered off to obtain 228 g of a butyl acetate solution of LiFSI (LiFSI concentration: 43% by mass).

[0085] Next, 228 g of the LiFSI butyl acetate solution obtained above was added to a 500 mL separable flask equipped with a dropping funnel, a condenser, and a distillate receiver. The pressure in the separable flask was reduced to 667 Pa using a vacuum pump, and the separable flask was immersed in an oil bath heated to 55 °C. The butyl acetate solution in the separable flask was slowly heated while stirring, thereby distilling off the solvent butyl acetate. Over a 10-minute period after the start of distillation, 1,2,4-trimethylbenzene was added to the separable flask as a poor solvent in an amount equal to the total amount of liquid collected in the distillate receiver. Subsequently, 1,2,4-trimethylbenzene was added to the separable flask every 10 minutes in an amount equal to the distillate. The reaction solution was concentrated while the ratio of butyl acetate (reaction solvent) to 1,2,4-trimethylbenzene in the system was varied, resulting in the precipitation of white crystals of LiFSI. The above procedure was repeated until the supernatant in the separable flask became transparent, and then the separable flask was cooled to room temperature. The resulting suspension of white LiFSI crystals was filtered, and the white LiFSI crystals were collected. Note that the time from the start of heating the butyl acetate solution of LiFSI to the end of the concentration process was 6 hours, and the time required for the white crystals to begin to precipitate was 2 hours.

[0086] Finally, the obtained white crystals of LiFSI were washed with a small amount of hexane, transferred to a flat-bottomed tray, and dried under reduced pressure at 55°C and 667 Pa for 12 hours to obtain white crystals of LiFSI (yield: 92.3 g).

[0087] Synthesis Example 2 32 g of lithium carbonate and 55 g of water were mixed and cooled in an ice bath to prepare a slurry. 139 g of bis(fluorosulfonyl)imide (manufactured by Nippon Shokubai Co., Ltd.) was added dropwise over 45 minutes to obtain 209 g of an aqueous solution containing 68.6 mass % of LiFSI.

[0088] A 500 mL separable flask equipped with a dropping funnel, a condenser, and a distillation receiver was charged with 209 g of the reaction solution obtained in the lithiation step and 78 g of dimethyl carbonate (DMC) to prepare a 50% by mass water-containing LiFSI DMC solution. The pressure in the separable flask was reduced to 5 kPa using a vacuum pump, and the flask was heated in an oil bath to distill off the water (reaction solvent) along with the DMC. Over a 10-minute period after the distillation began, a mass of DMC equal to the total weight of the solution collected in the distillation receiver was added to the separable flask. Subsequently, every 10 minutes, a mass of DMC equal to the distillate was added to the separable flask, varying the ratio of water (reaction solvent) to DMC in the system. The above procedure was repeated until the water content of the LiFSI DMC solution reached 53 ppm. The internal temperature remained between 45 and 60 °C, and a total of 3269 g of DMC was added. The resulting suspension was filtered to obtain a colorless, transparent solution of 50% by mass LiFSI in DMC.

[0089] Example 1 To the LiFSI (electrolyte) obtained in Synthesis Example 1, 5500 ppm of lithium amidosulfate was added as an additive (salt of a specific acid component), and the resulting mixture was dissolved in ethyl methyl carbonate (hereinafter referred to as "EMC") as a solvent to produce a solution (solvent composition) with a LiFSI concentration of 40 mass%.

[0090] Example 2 A solution was prepared in the same manner as in Example 1, except that the amount of lithium amidosulfate added was changed to 1300 ppm.

[0091] Example 3 A solution was prepared in the same manner as in Example 1, except that the amount of lithium amidosulfate added was changed to 200 ppm and the solvent was changed to DMC.

[0092] Example 4 A solution was prepared in the same manner as in Example 1, except that the amount of lithium amidosulfate added was changed to 70 ppm and the solvent was changed to DMC.

[0093] Comparative Example 1 The LiFSI obtained in Synthesis Example 1 was dissolved in EMC to prepare a solution with a LiFSI concentration of 40 mass %.

[0094] Comparative Example 2 To LiFSI containing 152 ppm of fluoride ions and 103 ppm of sulfate ions, 100 ppm of lithium amidosulfate was added as an additive (salt of a specific acid component), and the mixture was dissolved in DMC to produce a solution with a LiFSI concentration of 40 mass%.

[0095] 《Reference example 1》 The LiFSI obtained in Synthesis Example 1 was dissolved in EMC to prepare a solution with a LiFSI concentration of 40 mass %.

[0096] <<Evaluation of Composition>> The type of solvent, LiFSI concentration, amidosulfate ion concentration, fluoride ion concentration, sulfate ion concentration, water content, pH, and the like at the time of production (immediately after production, before storage) of each composition obtained in Examples 1 to 4, Comparative Examples 1 and 2, and Reference Example 1 were measured. 19 The presence or absence of peaks derived from decomposition products of LiFSI in the F-NMR spectrum (the "NMR peak" column in Table 1) is shown in Table 1. In addition, the pH and 19 Table 1 shows the presence or absence of peaks derived from decomposition products of LiFSI in the F-NMR spectrum.

[0097] [ 19 F-NMR measurement] The LiFSI concentration in the reaction solution and each composition is 19 F-NMR was used to measure the 19 F-NMR measurements were carried out using a Varian Unity Plus-400 (internal standard: trifluorotoluene, number of accumulations: 64). 19F-NMR was measured to determine whether or not one of two peaks [(1) between 60.0 and 61.0 ppm, (2) between 39.5 and 40.5 ppm] derived from decomposition products of LiFSI (chemical shift 55.4 ppm) was detected. Compositions in which no peak derived from decomposition products of LiFSI was detected were marked as "Good" (no peak), and compositions in which a peak was detected were marked as "Poor" (peak present).

[0098] [pH measurement] Each composition was diluted 10-fold with a 1:8 mixture of methanol (special reagent grade; manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.):ultrapure water (over 18.2 Ω·cm) to prepare a measurement solution, and the pH of each composition was measured using an automatic titrator COM-1700A (manufactured by Hiranuma Sangyo Co., Ltd.).

[0099] [Moisture measurement] The water content of each composition was measured using a Karl Fischer moisture analyzer AQ-2000 (manufactured by Hiranuma Sangyo Co., Ltd.) and using Aqualite RS-A (manufactured by Hiranuma Sangyo Co., Ltd.) as the generating liquid and Aqualite CN (manufactured by Hiranuma Sangyo Co., Ltd.) as the counter electrode liquid.

[0100] [Ion chromatography measurement] Each composition was diluted 100 times with ultrapure water (over 18.2 Ω cm) to prepare a measurement solution, and the concentrations of amidosulfate ions, fluoride ions, and sulfate ions contained in each composition were measured using an ion chromatography system ICS-3000 (manufactured by Nippon Dionex Co., Ltd.) under the following measurement conditions: (Ion chromatography measurement conditions) Separation mode: Ion exchange Eluent: 7-18mM KOH aqueous solution Detector: Electrical conductivity detector Column: Anion analysis column Ion PAC AS-17C (manufactured by Nippon Dionex Co., Ltd.)

[0101] [Table 1]

[0102] From the results in Table 1, in the compositions of Examples 1 to 4 in which a predetermined amount of lithium amidosulfate was added as the salt of a specific acid component, all of them showed a good 19 In the F-NMR spectrum, no peaks due to decomposition products of LiFSI were observed. On the other hand, in the composition of Comparative Example 1, after storage at 40°C for 2 months, 19 In the F-NMR spectrum, peaks derived from decomposition products of LiFSI were observed. Note that the composition of Reference Example 1, which was prepared in the same manner as Comparative Example 1 and had the same concentrations of each component as Comparative Example 1, showed a peak of 0.01% after storage at 25°C for 11 months or more. 19 In the F-NMR spectrum, no peaks due to decomposition products of LiFSI were observed.

[0103] Therefore, the compositions of Examples 1 to 4 contain a partial structure (amidosulfate ion) formed by ionic dissociation of a specific acid component (lithium amidosulfate) as an anion component at a predetermined concentration (a concentration of 50 ppm to 10,000 ppm relative to the electrolyte). Therefore, compared to the composition of Comparative Example 1, which does not contain amidosulfate ions at a predetermined concentration, the decomposition of LiFSI is suppressed, and the storage stability at high temperatures (e.g., 40°C) is found to be good. On the other hand, the composition of Comparative Example 1 (Reference Example 1) has good storage stability at room temperature (e.g., 25°C), but the decomposition reaction of LiFSI progresses during storage under high-temperature conditions, resulting in poor storage stability at high temperatures. Thus, compared to the composition of Comparative Example 1 (Reference Example 1), the compositions of Examples 1 to 4 can be stored for long periods not only at room temperature but also at high temperatures where decomposition of the sulfonylimide salt is promoted, i.e., they have good storage stability even at high temperatures.

[0104] In addition, the composition of Comparative Example 2 contained 100 ppm of amidosulfate ions, but after storing at 40°C for one month, 19In the F-NMR spectrum, peaks attributable to decomposition products of LiFSI were observed. Therefore, since the compositions of Examples 1 to 4 contain fluoride ions and / or sulfate ions at a predetermined concentration (100 ppm or less relative to the electrolyte) at the time of production, the decomposition of LiFSI is suppressed compared to the composition of Comparative Example 2, which contains a high concentration of fluoride ions and / or sulfate ions at the time of production (a concentration exceeding 100 ppm relative to the electrolyte), and it was found that the composition of Comparative Example 2 has poor storage stability at high temperatures due to the progress of decomposition reactions of LiFSI during storage.

[0105] Example 5 To the LiFSI obtained in Synthesis Example 1, 1500 ppm of lithium acetate was added as an additive (salt of a specific acid component), and the mixture was dissolved in EMC to produce a solution (solvent composition) with a LiFSI concentration of 40 mass %.

[0106] Example 6 A solution was prepared in the same manner as in Example 5, except that lithium acetate was changed to lithium carbonate as the additive.

[0107] Example 7 A solution was produced in the same manner as in Example 5, except that lithium acetate was changed to lithium phosphate as the additive.

[0108] Example 8 A solution was prepared in the same manner as in Example 5, except that lithium acetate was changed to amidosulfuric acid as the additive.

[0109] The type of solvent, LiFSI concentration, type and amount of additives, fluoride ion concentration, sulfate ion concentration, water content, pH, and the like at the time of production (immediately after production, before storage) of each composition obtained in Examples 5 to 8 were measured. 19 The presence or absence of peaks derived from decomposition products of LiFSI in the F-NMR spectrum (the "NMR peak" column in Table 2) is shown in Table 1. The pH and 19F-NMR spectra derived from decomposition products of LiFSI 19 The presence or absence of F-NMR peaks is shown in Table 2. The measurement methods, conditions, and evaluation methods are the same as those described above. Comparative Example 1 is also shown in Table 2.

[0110] [Table 2]

[0111] From the results in Table 2, in the compositions of Examples 5 to 8 to which a predetermined amount of lithium salt such as lithium acetate, lithium carbonate, or lithium phosphate or amidosulfuric acid was added, all of them showed good results after storage at 40°C for 4 months or more. 19 In the F-NMR spectrum, no peaks derived from decomposition products of LiFSI were observed. Therefore, it was found that the compositions of Examples 5 to 8, which contain specific acid components such as acetic acid, carbonate, phosphoric acid, and amidosulfuric acid as anion components at predetermined concentrations, suppress the decomposition of LiFSI compared to the solution of Comparative Example 1, which does not contain specific acid components, and have good storage stability even at high temperatures. [Industrial Applicability]

[0112] As described above, the present disclosure is suitable for compositions that can be used as electrolyte materials or electrolytes.

Claims

1. A composition comprising an electrolyte, a solvent, and an anionic component, the electrolyte comprises a sulfonylimide salt; the anion component contains an acid component having an acid dissociation constant pKa (a first stage acid dissociation constant pKa1 for a multiply ionizable acid) of 0 to 6.5 in a concentration of 50 ppm to 10,000 ppm relative to the electrolyte; pH is 5 or more, The composition, wherein the anion component comprises at least one selected from the group consisting of an amidosulfuric acid component, a carbonate component, and a phosphate component.

2. 10. The composition of claim 1, wherein the solvent comprises a carbonate solvent.

3. 3. The composition according to claim 2, wherein the carbonate solvent is a chain carbonate solvent.

4. 2. The composition according to claim 1, wherein the solvent consists solely of a chain carbonate solvent.

5. A composition comprising an electrolyte, a solvent, and an anionic component, the electrolyte comprises a sulfonylimide salt; the anion component contains an acid component having an acid dissociation constant pKa (a first stage acid dissociation constant pKa1 for a multiply ionizable acid) of 0 to 6.5 in a concentration of 50 ppm to 10,000 ppm relative to the electrolyte; the solvent consists solely of a chain carbonate solvent, A composition characterized by having a pH of 5 or higher.

6. 6. The composition according to claim 1, wherein the electrolyte comprises lithium bis(fluorosulfonyl)imide.

7. 7. The composition according to claim 1, wherein the composition contains water at a concentration of 0.1 ppm to 1000 ppm relative to the electrolyte.

8. 8. The composition according to claim 1, wherein the content of the sulfonylimide salt is 10% by mass or more based on the total mass of the composition.

9. the amidosulfuric acid component is at least one selected from the group consisting of amidosulfuric acid and salts thereof, and amidosulfuric acid derivatives and salts thereof; 2. The composition according to claim 1, wherein the amidosulfonic acid derivative and its salt are compounds represented by the following general formula (2): 【Chemical 1】 (In formula (2), R １ , R ２ represents H (hydrogen atom), a hydroxyl group, or an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aryl group having 6 to 16 carbon atoms, an aralkyl group having 7 to 16 carbon atoms, or an alkanoyl group having 2 to 16 carbon atoms, which may have a substituent, and may contain a heteroatom; R １ and R ２ may form a ring structure. １ , R ２ When R is the above group other than H, they may be the same or different (R １ , R ２ are not identical when H (R １ and R ２ is not H at the same time. M represents H (hydrogen atom) or a metal atom.

10. 2. The composition according to claim 1, wherein the amidosulfuric acid component is at least one selected from the group consisting of amidosulfuric acid and alkali metal amidosulfates.

11. 2. The composition of claim 1, wherein the amidosulfate component is an alkali metal amidosulfate.

12. 12. The composition according to claim 1, wherein the concentration of sulfate ions is 100 ppm or less relative to the electrolyte.

13. An electrolyte material comprising the composition according to any one of claims 1 to 12.

14. An electrolyte solution prepared using the electrolyte material according to claim 13.

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