Electrolyte composition and battery

Abstract

To provide an electrolyte composition capable of conducting a sufficiently large current at a low voltage.SOLUTION: An electrolyte composition includes a polymer (A), an ionic compound, and a nonionic organic solvent. The polymer (A) has an anionic functional group and an alkali metal ion as a counter cation of the anionic functional group. In the polymer (A), the energy required for dissociation of a lithium ion from the anionic functional group is 150 kcal / mol or more.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to electrolyte compositions and batteries. [Background technology]

[0002] Batteries such as lithium ion batteries that charge and discharge with the movement of metal ions between positive and negative electrodes have been actively researched due to their high capacity. As electrolytes for lithium ion batteries and the like, solutions of lithium salts containing organic solvents or ionic liquids are known, but research on solid electrolytes, polymer electrolytes, and the like is being conducted from the viewpoint of safety and processability (Patent Documents 1 and 2). In addition to lithium ion batteries, research is also being conducted on batteries that use other alkali ions such as sodium and potassium, which are more abundant than lithium. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2007 / 125845 [Patent Document 2] Patent Publication No. 2021-88695 Summary of the Invention [Problem to be solved by the invention]

[0004] Polymer electrolytes are generally more easily adhered to electrodes than solid electrolytes, and therefore tend to have a smaller contact resistance between the electrodes. However, the inventors of the present invention have conducted extensive research and found that in polymer electrolytes containing polymers having functional groups that serve as counter anions to alkali metal ions, the resistance of the functional groups themselves is high, and there is room for improvement. Furthermore, it would be useful if this improvement could reduce the resistance between the electrodes and the electrolyte.

[0005] The present disclosure has been made in consideration of the above circumstances, and has an object to provide an electrolyte composition capable of passing a sufficiently large current at a low voltage, and a battery including the electrolyte composition. [Means for solving the problem]

[0006] The present disclosure includes the following embodiments. [1] a polymer (A) having an anionic functional group and an alkali metal ion as a counter cation of the anionic functional group, the energy of dissociation between the lithium ion and the anionic functional group being 150 kcal / mol or more; An ionic compound; a non-ionic organic solvent; and [2] The electrolyte composition according to [1], wherein the transport number of the alkali metal ion at 25° C. is 0.5 or more. [3] The electrolyte composition according to [1] or [2], wherein the alkali metal ion contains a lithium ion or a sodium ion. [4] The electrolyte composition according to any one of [1] to [3], wherein the nonionic organic solvent contains one or more solvents selected from the group consisting of carbonate-based solvents, ether-based solvents, fluorine-based solvents, nitrile-based solvents, lactone-based solvents, phosphate-based solvents, and sulfone-based solvents. [5] The electrolyte composition according to any one of [1] to [4], wherein the anionic functional group contains one or more groups selected from the group consisting of an alkali metal substituted sulfonic acid group and an alkali metal substituted carboxylic acid group. [6] The electrolyte composition according to any one of [1] to [5], wherein the polymer (A) does not hydrolyze in air. [7] A battery comprising any one of the electrolyte compositions according to [1] to [6]. Effect of the Invention

[0007] According to the present disclosure, it is possible to provide an electrolyte composition capable of passing a sufficiently large current at a low voltage, and a battery including the electrolyte composition. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a graph showing the results of measuring the maximum direct current density using the electrolyte composition of Example 4. [Diagram 2] FIG. 2 is a graph showing the results of measuring the maximum direct current density using the electrolyte composition of Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The electrolyte composition according to an embodiment of the present disclosure includes a polymer (A) having an anionic functional group and an alkali metal ion as a counter cation of the anionic functional group, an ionic compound, and a nonionic organic solvent. The polymer (A) has an energy of 150 kcal / mol or more when the lithium ion and the anionic functional group dissociate. Hereinafter, the "energy when the lithium ion and the anionic functional group dissociate" is also simply referred to as "dissociation energy". The dissociation energy is the energy when the alkali metal ion possessed by the polymer dissociates with the anionic functional group. In addition, the polymer having an anionic functional group and an alkali metal ion as a counter cation of the anionic functional group is also referred to as polymer (A). As described above, the electrolyte composition of this embodiment has low resistance, which facilitates the movement of Li cations at the interface between the electrode and the electrolyte, and can be driven at a voltage that is sufficiently practical. In addition, the electrolyte composition of this embodiment also tends to improve the selective transport of lithium ions.

[0010] The electrolyte composition contains an ionic compound and a nonionic organic solvent while using a polymer (A) having an anionic functional group that has a large dissociation energy and strongly binds alkali metal ions, and can pass a sufficient amount of current even at a low voltage. The reason why such an effect is obtained is unclear, but the inventors presume as follows. That is, in a nonionic organic solvent, the anionic functional group of the polymer (A) can strongly bind alkali metal ions, but by adding an ionic compound, the cationic portion of the ionic compound interacts with the anionic functional group and the anionic portion of the ionic compound interacts with the alkali metal ion. This weakens the binding force felt by the alkali metal ion in the electrolyte composition, and the conductivity of the alkali metal ion in the electrolyte can be improved. This action can reduce the resistance of the electrolyte composition. In addition, as an anionic functional group with a small dissociation energy, for example, a sulfonylimide group or the like is considered, but the synthesis of a polymer having such a functional group often requires a multi-step process and tends to be expensive. Therefore, the technology of the present disclosure is useful in that even if a polymer has an anionic functional group with a large dissociation energy, the polymer can be used to obtain a battery with sufficient performance. In the electrolyte composition of the present embodiment, the resistance between the electrode and the electrolyte interface is improved.

[0011] In any case in this specification, examples of the "substituent" include both an organic group and a group other than an organic group (an inorganic group). In this specification, the term "organic group" refers to a group having a chemical structure in which at least one hydrogen atom is removed from an organic compound. In any case, the term "organic group" refers to a hydrocarbon group or a group in which some carbon atoms of a hydrocarbon group are replaced with heteroatoms, a group in which at least one or more hydrogen atoms of a hydrocarbon group or a group in which some carbon atoms of a hydrocarbon group are replaced with heteroatoms, etc., regardless of the valence of the organic group, can be exemplified. When the organic group has a ring structure, the ring may be either a heterocycle or a carbocycle, or may be either a monocycle or a condensed ring. In any case herein, the hydrocarbon group may be either an aliphatic hydrocarbon group or an aromatic hydrocarbon group. In any case herein, the aliphatic hydrocarbon group may be either a straight-chain hydrocarbon group, a branched-chain hydrocarbon group, or a cyclic hydrocarbon group. In any case herein, the hydrocarbon group may be either a saturated hydrocarbon group or an unsaturated hydrocarbon group. In this specification, an aromatic hydrocarbon group is a hydrocarbon group having an aromatic moiety such as a benzene ring, which may have an aliphatic moiety, and a cyclic hydrocarbon group is a hydrocarbon group having an aliphatic carbon ring moiety, which may have a straight-chain or branched-chain aliphatic moiety. The heteroatom substituting the carbon atom is not particularly limited, and examples thereof include a boron atom, an oxygen atom, a nitrogen atom, a silicon atom, a phosphorus atom, a sulfur atom, etc. Specifically, the organic group may contain a linking group containing a heteroatom, such as -O- (ether bond), -S- (thioether bond), a sulfonyl group, a sulfinyl group, a secondary amino group, or a tertiary amino group. In any case in this specification, specific examples of the organic group include a substituted or unsubstituted hydrocarbon group, a group having a chemical structure formed by replacing one or more carbon atoms (methylene groups) in a hydrocarbon group with a linking group containing a heteroatom (the linking group may be a divalent linking group) such as -O- (ether bond), -S- (thioether bond), -C(=O)-, -C(=O)O-, -C(=O)NR- (R is a monovalent organic group), or a group in which a hydrogen atom of the group is substituted with a substituent such as a halogen atom, a group having a heterocycle, and the like. In any case in this specification, examples of inorganic groups include both electron-withdrawing groups and electron-donating groups, and specific examples thereof include halogen atoms, -NH2, -NH3 + , -CN, sulfonic acid groups and their salts or esters, -NO2, and the like.

[0012] <Polymers with the ability to preferentially conduct alkali metal ions> The polymer (A) may be a polymer capable of preferentially conducting alkali metal ions. A polymer capable of preferentially conducting alkali metal ions (hereinafter also simply referred to as a polymer) may be one that satisfies at least one of the following conditions (A) and (B). The above polymer may simply be referred to as a polymer capable of conducting alkali metal ions. (A) When the transport number of alkali metal ions is measured at room temperature (25°C) for a composition containing 33 mass% of a polymer and 67 mass% of a nonionic plasticizer, the transport number of alkali metal ions is 0.4 or more. (B) When the transport number of the alkali metal ion is measured at room temperature (25°C) for a composition containing 31.9 mass% of a polymer, an alkali metal salt, and the remainder of a nonionic plasticizer in an alkali metal ion concentration of 0.3 mol / L, the transport number of the alkali metal ion is 0.4 or more. With respect to (A) and (B), the transport number of the alkali metal ion may be 0.5 or more, 0.6 or more, or 0.7 or more. The alkali metal ions contained in the composition may be counter cations for the anionic functional groups of the polymer. The non-ionic plasticizer may be at least one of an organic solvent and other resins such as fluorine-based resins. The organic solvent may be an aprotic solvent. The aprotic solvent may be at least one selected from the group consisting of carbonate-based solvents, fluorine-based solvents, and ether-based solvents. The organic solvent may be a mixed solvent of ethylene carbonate and propylene carbonate (volume ratio 1:1). The fluororesin is preferably a resin having a carbon chain as the main chain. The carbon chain may be formed by radical polymerization of an ethylene saturated group. The fluororesin may be PVDF-HFP.

[0013] The polymer (A) has an anionic functional group having an energy of 150 kcal / mol or more when the lithium ion dissociates from the anionic functional group. An example of a functional group containing such an anionic functional group is an alkali metal-modified group. The alkali metal-modified group may contain one or more groups selected from the group consisting of an alkali metal-modified sulfonic acid group, an alkali metal-modified carboxylic acid group, and an alkali metal-modified phenolic hydroxyl group.

[0014] In this specification, an alkali metal-modified group refers to a group in which an anionic functional group, which is a conjugate base of the acid form of the group, forms a salt with an alkali metal ion. Specific examples include an alkali metal-modified sulfonic acid group, an alkali metal-modified carboxylic acid group, and an alkali metal-modified phenolic hydroxyl group. An alkali metal-modified sulfonic acid group is a -SO3A group ([-SO3]) in which the H of a sulfonic acid group (-SO3H group) is replaced with an alkali metal element A. - A + An alkali metal carboxylate group is a -COOA group ([-COO] group) in which the H of the carboxylate group (-COOH group) is replaced with an alkali metal element A. - A + An alkali metal phenolic hydroxyl group is a phenolic hydroxyl group in which the H of the -OH group is replaced with an alkali metal element A, forming an -OA group (-O - A + This refers to the group.

[0015] The structure of the polymer (A) is not particularly limited, but examples thereof include those having a carbon chain as the main chain, and the carbon chain may be formed by radical addition polymerization of a monomer having an ethylenically unsaturated group.

[0016] The alkali metal element A may include at least one selected from the group consisting of lithium, sodium, potassium, rubidium, and cesium, may include at least one selected from the group consisting of lithium, sodium, and potassium, may include at least one of lithium and sodium, or may include lithium.

[0017] The content of one kind of alkali metal element among the alkali metal elements contained in the polymer (A) may be 80 mol% or more, may be 85 mol%, or may be 90 mol%. The one kind of alkali metal element may be potassium, sodium, or lithium, or may be sodium or lithium, or may be lithium.

[0018] The structural unit (A) may contain at least one of a structural unit represented by the following formula (A1) and a structural unit represented by the following formula (A2). [ka] (In formula (A1), Y is a monovalent group which has been converted to an alkali metal. R 1 ~R 3 are each independently a hydrogen atom or a monovalent substituent, or R 1 and R 2 One of them is R 3 R forms a ring together with 1 ~R 3 may have the above-mentioned alkali metal group. [ka] (In formula (A2), Z is a divalent group which has been converted to an alkali metal. R 4 and R 5 are each independently a hydrogen atom or a monovalent substituent, or R 4 and R 5 are joined together to form a ring. R 4 and R 5 may have the above-mentioned alkali metal group. In addition, in formula (A1), R 1 ~R 3 and the structure excluding Y, and R 4 , R 5 The structure without Z is also simply called an ethylene unit.

[0019] In formula (A1), Y may contain one or more groups selected from the group consisting of an alkali metal substituted sulfonylimide group, an alkali metal substituted sulfonic acid group, an alkali metal substituted carboxylic acid group, and an alkali metal substituted phenolic hydroxyl group, or may contain one or more groups selected from the group consisting of an alkali metal substituted sulfonic acid group, and an alkali metal substituted carboxylic acid group. One or more functional groups may be used as Y.

[0020] In formula (A1), R 1 ~R 3 The monovalent substituent as R may be a monovalent organic group. 1 ~R 3 When R is a monovalent substituent, examples of the substituent include a monovalent organic group. The number of carbon atoms in the monovalent organic group may be 1 to 20, 1 to 15, 1 to 10, 1 to 5, or 1 to 3. 1 ~R 3 At least one of may be a hydrogen atom, and all of may be hydrogen atoms.

[0021] In formula (A1), R 1 and R 2 One of them is R 3 When it forms a ring with R 1 or R 2 and R 3 In formula (A2), R forms a divalent substituent bonded to each of the two carbon atoms of the ethylene unit of formula (A1). 4 and R 5 When the are joined together to form a ring, R 4 and R 5 form a divalent substituent bonded to each of the two carbon atoms of the ethylene unit of formula (A1). These rings may be either carbocyclic or heterocyclic. The number of ring members of these rings may be 4 to 10, 5 to 8, or 5 or 6. A substituent may be bonded to the carbon atom or hetero atom that is a ring member.

[0022] In formula (A1), when Y contains an alkali metal-modified carboxylic acid group (-COOA group, A is an alkali metal), Y may be a -COOA group itself, or may be a monovalent organic group having a -COOA group. When Y is a monovalent organic group, the number of carbon atoms in the organic group may be 1 to 20, 1 to 15, 1 to 10, 1 to 5, or 1 to 3. The monovalent organic group may have one or more -COOA groups, or may have one -COOA group. Y may have an electron-withdrawing group such as a halogen atom in addition to the -COOA group.

[0023] In formula (A1), Y is -R 9 -COOA, where R 9 is a divalent organic group or a covalent bond. The number of carbon atoms in the divalent organic group may be 1 to 19, 1 to 14, 1 to 9, 1 to 4, or 1 or 2.

[0024] In the formula (A1), when Y has an alkali metal-substituted phenolic hydroxyl group, Y is, for example, R 10 -Y 2 In this case, R 10 is a divalent substituent (linking group). 2 may be a group having one or more -OA groups (A is an alkali metal element) directly bonded to a carbon atom that is a member of an aromatic ring such as a benzene ring, a naphthalene ring, or an anthracene ring. The aromatic ring may be condensed with other ring structures. For example, Y 2 may have a group represented by any one of the following formulas (A21) to (A26). [ka] (In formula (A21), R A1 ~R A5 At least one of the groups is an -OA group, and the rest are hydrogen atoms or monovalent substituents. A3 The group may be an -OA group. In formula (A22), R B1~ R B7 At least one of the groups is an -OA group, and the rest are hydrogen atoms or monovalent substituents. B3 ~R B6 At least one of the groups may be an -OA group. In formula (A23), R C1~ R C9 At least one of the groups is an -OA group, and the rest are hydrogen atoms or monovalent substituents. C2 ~R C8 At least one of the groups may be an -OA group. In formula (A24), R D1~ R D6 At least one of the groups is an -OA group, and the rest are hydrogen atoms or monovalent substituents. D3~ R D6 At least one of the groups may be an -OA group. In formula (A25), R E1~ R E9 At least one of the groups is an -OA group, and the rest are hydrogen atoms or monovalent substituents. E2 ~R E8 At least one of the groups may be an -OA group. In formula (A26), R F1~ R F9 At least one of the groups is an -OA group, and the rest are hydrogen atoms or monovalent substituents. F1~ R F9 At least one of the groups may be an -OA group.

[0025] The groups represented by formulae (A21) to (A26) may have 1 to 3 -OA groups, may have 1 or 2 -OA groups, or may have 1 -OA group.

[0026] In the formulae (A21) to (A26), the monovalent substituent is preferably an electron-withdrawing group. Examples of the electron-withdrawing group include a halogen atom, a sulfonic acid group or a salt thereof, a sulfonic acid ester, a nitro group, and a nitrile group. The halogen atom may be any of F, Cl, Br, and I.

[0027] In addition, in formulae (A21) to (A26), the monovalent substituent may be an organic group having 1 to 20 carbon atoms. The number of carbon atoms in the organic group may be 1 to 15, 1 to 10, 1 to 5, or 1 to 3.

[0028] The groups represented by formulae (A21) to (A26) may have 1 to 3 -OA groups, may have 1 or 2 -OA groups, or may have 1 -OA group.

[0029] In the formulae (A21) to (A26), the monovalent substituent is preferably an electron-withdrawing group. Examples of the electron-withdrawing group include a halogen atom, a sulfonic acid group or a salt thereof, a sulfonic acid ester, a nitro group, and a nitrile group. The halogen atom may be any of F, Cl, Br, and I.

[0030] In addition, in formulae (A21) to (A26), the monovalent substituent may be an organic group having 1 to 20 carbon atoms. The number of carbon atoms in the organic group may be 1 to 15, 1 to 10, 1 to 5, or 1 to 3.

[0031] R 10 R may be a divalent organic group. The number of carbon atoms in the divalent organic group may be 1 to 15, 1 to 10, 1 to 8, or 1 to 5. 10 may have a heterocycle or a ring having an imide group.

[0032] When Y is a sulfonic acid group modified with an alkali metal, examples of Y include a group represented by the following formula (A3). [ka] (In formula (A3), R 19 is a covalent bond or a divalent organic group. A is an alkali metal element.

[0033] In formula (A3), the divalent organic group may have 1 to 20 carbon atoms, 1 to 15 carbon atoms, 1 to 10 carbon atoms, 1 to 5 carbon atoms, or 1 to 3 carbon atoms.

[0034] In the formula (A3), examples of the alkali metal substituted sulfonic acid group include -SO3A, -CH2-SO3A, -C6H4-SO3A and the like.

[0035] In formula (A2), Z is bonded to two carbon atoms of the ethylene unit to form a ring. The ring may be either a carbocyclic ring or a heterocyclic ring. The ring may be either aliphatic or aromatic. Examples of the heterocyclic ring include a ring having an imide group such as a maleimide ring. The ring may have bonded thereto, for example, one or more groups selected from the group consisting of an alkali metal substituted sulfonic acid group, an alkali metal substituted carboxylic acid group, and an alkali metal substituted phenolic hydroxyl group. The number of carbon atoms in Z may be 1 to 20, 1 to 15, 2 to 10, or 3 to 8.

[0036] The polymer (A) may have an anionic functional group with a dissociation energy of 150 to 300 kcal / mol, 155 to 275 kcal / mol, 157 to 250 kcal / mol, or 160 to 200 kcal / mol. The dissociation energy may be calculated by quantum mechanical calculation. For example, structural optimization is performed using Gaussian 16 and M06 / 6-31G* as a combination of functional and basis function. Structural optimization is performed for each of the alkali metal cation (M+), the anionic functional group (Anion-), and the structure (MA) in which the two interact with each other, and the energy of the optimized structure is obtained. Next, the dissociation energy is calculated by the following formula using the total energy calculated by structural optimization for each of the energies. M + The energy possessed by E M+ , the energy possessed by Anion- is E Anion- And the energy that MA has is E MA In addition, EAnion- may be calculated using the corresponding anion, not the anionic functional group itself. When the bonding part of the functional group is a carbon atom or a heteroatom of an aromatic ring, an anion in which hydrogen is bonded to the bonding atom may be used as the anion corresponding to the anionic functional group. For example, when the anionic functional group is -Ph-SO3 - (phenylsulfonic acid group), benzenesulfonic acid anion may be used as the corresponding anion. In this case, when determining the dissociation energy with lithium ion, lithium benzenesulfonate is used as the compound corresponding to MA. When the bonding site of the anionic functional group is other than an aromatic ring, an anion having a methyl group bonded to the bonding site may be used as the corresponding anion. For example, -O - (hydroxyl group) is CH3O - In this case, when determining the dissociation energy with lithium ions, CH3OLi is used as the compound corresponding to MA. Dissociation energy = E M+ +E Anion- -E MA

[0037] The dissociation energies of the functional groups calculated as above are shown in Table 1 below. [Table 1]

[0038] The polymer (A) may have at least one of an anionic functional group having an alkali metal ion as a counter cation and a dissociation energy of less than 150 kcal / mol (also referred to as a second anionic functional group) and a functional group having a function as an anion receptor, in addition to the anionic functional group having an energy of 150 kcal / mol or more when the lithium ion and the anionic functional group dissociate. These functional groups may be contained in the same structural unit as the structural unit (A), or may be contained in a different structural unit. The structural unit having a functional group having a function as an anion receptor is also referred to as a structural unit (B). The electrolyte composition of the present embodiment may contain a polymer (also referred to as a polymer (B)) that does not have an anionic functional group having a dissociation energy of 150 kcal / mol or more, and has at least one of an anionic functional group having a dissociation energy of less than 150 kcal / mol and a functional group having a function as an anion receptor. Examples of the second anionic functional group include an alkali metal sulfonylimide group. An alkali metal sulfonylimide group is a -SO2-NA-SO2- group ([-SO2-N-SO2-]) in which the H of the sulfonylimide acid group (-SO2-NH-SO2- group) is replaced with an alkali metal element A. - A + This refers to the group.

[0039] When the polymer (A) has the structural unit (B), the structural unit (B) functions as an anion receptor. The anion receptor is a chemical species that captures anions by forming electrostatic interactions, hydrogen bonds, acid-base complexes, etc. with the anion. The structural unit (B) captures the counter anion of the alkali metal ion in the alkali metal salt, and promotes dissociation between the counter anion and the alkali metal ion. This increases the mobility of the alkali metal ion. On the other hand, the mobility of the counter anion decreases because the counter anion is captured by the polymer via the structural unit (B). As a result, it is believed that the transport number of the alkali metal ion is improved. In addition, since the mobility of the alkali metal ion is increased, the conductivity of the alkali metal ion also tends to improve. Low molecular weight chemical species (compounds, etc.) that function as anion receptors are known, and examples of such compounds include those described in U.S. Patent Nos. 6,022,643, 5,705,689, and 6,120,941.

[0040] The functional group having the function of an anion receptor may have Lewis acidity. In this case, the functional group can capture the anion by accepting the unshared electron pair of the anion and forming an acid-base complex. Such a functional group may include a functional group having an electron-deficient atom. The electron-deficient atom refers to an atom that is covalently bonded to another atom but the electrons in the outermost shell of the atom do not form an octet. The electron-deficient atom may be an atom belonging to Group 13 of the periodic table, and more specifically, may be at least one of aluminum and boron, or may be boron.

[0041] The functional group having a function as an anion receptor may be a group having an azaether moiety. The group having an azaether moiety is a group having an azaether compound as a substituent, and the azaether compound is a compound in which -O- of an ether compound is replaced with -NRE- (wherein RE is a hydrogen atom or an organic group). The azaether moiety may be either a linear azaether moiety or a cyclic azaether moiety, or may have both a linear azaether moiety and a cyclic azaether moiety. The group having an azaether moiety may have an electron-withdrawing group, for example, in the hydrocarbon moiety.

[0042] The structural unit (B) may contain at least one structural unit represented by the following formula (B): 11 ~R 13 The structure without W is also simply called an ethylene unit. [ka] (In formula (B), W is a functional group having a function as an anion receptor, and R 11 ~R 13 are each independently a hydrogen atom or a monovalent substituent, or R 11 and R 13 One of them is R 12 and form a ring, and the other is a hydrogen atom or a monovalent substituent. * indicates the position where the structural unit (B) is bonded to another structural unit. R 11 ~R 13 may be hydrogen atoms, or all of may be hydrogen atoms.)

[0043] In formula (B), R 11 ~R 13 is a monovalent substituent, the monovalent substituent may be a monovalent organic group. The number of carbon atoms in the organic group may be 1 to 20, 1 to 15, 1 to 10, 1 to 5, or 1 to 3.

[0044] In formula (B), R11 ~R 13 is a monovalent substituent, the monovalent substituent may have an electron-withdrawing group or may be an electron-withdrawing group itself. The electron-withdrawing group may be bonded to the monovalent organic group, or the monovalent organic group may be an electron-withdrawing group. Examples of the electron-withdrawing group include a halogen atom, a sulfonic acid group or a salt thereof, a sulfonic acid ester, a nitro group, and a nitrile group. The halogen atom may be any of a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0045] In formula (B), R 11 and R 13 One of them is R 12 When it forms a ring with R 11 or R 12 and R 13 form a divalent substituent bonded to each of the two carbon atoms of the ethylene unit of formula (B). These rings may be either carbocyclic or heterocyclic. The number of ring members of these rings may be 4 to 10, 5 to 8, or 5 or 6. A substituent may be bonded to the carbon atom or hetero atom that is a ring member.

[0046] In formula (B), W preferably has a group represented by the following formula (B1). [ka] (In formula (B1), W B is an atom in group 13 of the periodic table, and R 15 is a covalent bond or a divalent organic group, R 16 and R 17 R are each independently a hydrogen atom, an -OH group, a halogen atom, or a monovalent organic group, or are joined together to form a ring. 16 and R 17 may be the same group or different groups.)

[0047] In formula (B1), W B may be at least one of an aluminum atom and a boron atom, and may be a boron atom.

[0048] In formula (B1), R 15 When R is a divalent organic group, the divalent organic group may have 1 to 20 carbon atoms, 1 to 15 carbon atoms, 1 to 10 carbon atoms, 1 to 5 carbon atoms, or 1 to 3 carbon atoms. 15 When is a divalent organic group, the organic group is R 15 is a hydrocarbon group, a halogen-substituted hydrocarbon group, or a hydrocarbon group or a halogen-substituted hydrocarbon group connected via an ether bond to W B The halogen-substituted hydrocarbon group may be a hydrocarbon group in which some or all of the hydrogen atoms have been substituted with halogen atoms, and may be a partially fluorinated hydrocarbon group or a fully fluorinated hydrocarbon group. 15 may be a covalent bond.

[0049] In formula (B1), R 16 or R 17 When is a halogen atom, R 16 or R 17 may be any one of a fluorine atom, a chlorine atom, a bromine atom and an iodine atom, and may be a fluorine atom.

[0050] In formula (B1), R 16 or R 17 When R is a monovalent organic group, the number of carbon atoms in the monovalent organic group may be 1 to 20, 1 to 15, 1 to 10, 1 to 5, or 1 to 3. 6 or R 7 is a hydrocarbon group, a halogen-substituted hydrocarbon group, or a hydrocarbon group or a halogen-substituted hydrocarbon group bonded to W via an ether bond B The halogen-substituted hydrocarbon group may be a hydrocarbon group in which some or all of the hydrogen atoms have been substituted with halogen atoms, and may be a partially fluorinated hydrocarbon group or a fully fluorinated hydrocarbon group.

[0051] The group represented by formula (B1) may be a group represented by the following formula (B1a) or a group represented by the following formula (B1b). [ka] (In formula (B1a), R 15 is a covalent bond or a divalent organic group, and X 11 and X 12 Each X is independently an oxygen atom or a covalent bond. 11 If is a covalent bond, R 21 is a hydrogen atom, a halogen atom, or a monovalent organic group. 11 is an oxygen atom, R 21 is a hydrogen atom or a monovalent organic group. 12 If is a covalent bond, R 22 is a hydrogen atom, a halogen atom, or a monovalent organic group. 12 is an oxygen atom, R 22 is a hydrogen atom, a halogen atom, or a monovalent organic group. 11 and X 12 When each is an oxygen atom, they may be oxygen atoms forming an ether bond. [ka] (In formula (B1b), R 15 is a covalent bond or a divalent organic group, and X 13 and X 14 are each an oxygen atom or a covalent bond, and R 23 is a divalent organic group.

[0052] In formula (B1a), R 21 Or R 22When R is a monovalent organic group, the monovalent organic group may be a monovalent hydrocarbon group or a monovalent halogen-substituted hydrocarbon group. The number of carbon atoms in the monovalent organic group may be 1 to 20, 1 to 15, 1 to 10, 1 to 5, or 1 to 3. The halogen-substituted hydrocarbon group may be a hydrocarbon group in which some or all of the hydrogen atoms have been substituted with halogen atoms, and may be a partially fluorinated hydrocarbon group or a fully fluorinated hydrocarbon group. 21 Or R 22 When is a halogen atom, the halogen atom may be a fluorine atom.

[0053] In formula (B1a), R 21 and R 22 are each independently -F, -CH3, -C2H5, -C3H7, -C6H5 (phenyl group), -C6H n F 5-n (n is an integer of 0 to 4, and may be an integer of 0 to 3), -CF3, -CH2CF3, -CH2CF3CF7, -CH(CF3)2, -C(CF3)2-C6H5, -C(CF3)3, -C6H n (CF3) 5-n (n is an integer of 0 to 4, and may be 1 or 2.)

[0054] In formula (B1b), the divalent organic group may have 1 to 20 carbon atoms, 1 to 15 carbon atoms, 2 to 10 carbon atoms, or 3 to 8 carbon atoms. The divalent organic group may be a hydrocarbon group or a halogen-substituted hydrocarbon group. The halogen-substituted hydrocarbon group may be a hydrocarbon group in which some or all of the hydrogen atoms have been substituted with halogen atoms, and may be a partially fluorinated hydrocarbon group or a fully fluorinated hydrocarbon group.

[0055] In formula (B1b), R 23 -C2H4-, -C3H6-, -C4H8-, -C5H 10 -, -C6H 12 -, -C7H 14 -, -C8H 16 -, -C9H 18 -, -C10 H 20 -, etc., in which the hydrogen atoms are partially or completely replaced with fluorine. More specifically, R 23 may be -C(CH3)2-C(CH3)2-.

[0056] The anionic functional group having a dissociation energy of less than 150 kcal / mol may be contained in, for example, a structural unit having a structure represented by the following formula (A4). [ka] (In formula (A4), X is a divalent organic group having 1 to 20 carbon atoms, and Y 1 is a halogen atom or a monovalent organic group having 1 to 20 carbon atoms, A + is an alkali metal ion, and * indicates the position where the structural unit (A4) is bonded to another structural unit.

[0057] In formula (A4), the number of carbon atoms owned by X may be 1 to 15, 2 to 10, or 3 to 8. The hydrocarbon group represented by X may be a phenylene group, an alkylene group having 1 to 8 carbon atoms, a polyoxyalkylene group, or a group in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups have been substituted with halogen atoms such as fluorine atoms, or may be a phenylene group or a substituted phenylene group substituted with an alkyl group, a halogen atom, an electron-withdrawing group, or the like.

[0058] In formula (A4), Y 1 When Y is a monovalent organic group, 1 The number of carbon atoms in Y may be 1 to 15, 1 to 10, 1 to 8, 1 to 5, or 1 to 3. 1The hydrocarbon group as Y may be a phenyl group, an alkyl group having 1 to 5 carbon atoms, or a group in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups have been substituted with halogen atoms such as fluorine atoms, a fluorinated alkyl group having 1 to 5 carbon atoms, or a fluorinated alkyl group having 1 to 3 carbon atoms such as a trifluoromethyl group. The fluorinated alkyl group may be a fully fluorinated alkyl group. 1 When is a halogen atom, the halogen atom may be a fluorine atom or a chlorine atom, and may be a fluorine atom.

[0059] The polymer (A) may have a structural unit (also referred to as structural unit (C)) that does not contain either an anionic functional group having an alkali metal ion as a counter cation or a functional group that functions as an anion receptor. The polymer (B) may also have a structural unit (C). Examples of the structural unit (C) include a structural unit represented by the following formula (C). [ka] (In formula (C), R 25 is a hydrogen atom or a monovalent substituent, R 26 ~R 28 are each independently a hydrogen atom or a monovalent substituent, or R 26 and R 27 One of the groups is a hydrogen atom or a monovalent substituent, and the other is R 28 It forms a ring together with *. The * is the bond between the structural unit (C) and other structural units.

[0060] In formula (C), R 25 may be a monovalent organic group. The monovalent organic group is -Z 1 -R 29 R may be a group represented by 25 The number of carbon atoms in Z may be 1 to 40, 1 to 20, 2 to 15, or 4 to 13. 1is a divalent linking group, for example, a covalent bond, -O-, -S-, -C(=O)-, -C(=O)O-, -OC(=O)-, -C(=O)NR 38 -OR-NR 39 Z may be a group represented by C(=O)-. 1 is a covalent bond, -O-, -S-, -C(=O)-, -C(=O)O- or -OC(=O)-, R 29 is a hydrogen atom or a monovalent organic group. Z is -C(=O)NR 38 -If R 29 , R 38 are each a hydrogen atom or a monovalent organic group, or R 29 is R 38 The divalent linking group Z 1 But -NR 39 If C(=O)-, R 29 , R 39 are each a hydrogen atom or a monovalent organic group, or R 29 is R 39 Together with R it forms a ring. 29 , R 38 and R 39 The monovalent organic group as R may have 1 to 20 organic groups, or 1 to 10 organic groups. 38 When Z is a monovalent organic group, it may be a monovalent hydrocarbon group having 1 to 20 carbon atoms. 1 is a covalent bond or -C(=O)O-, R 29 Z may be a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms. 1 is a covalent bond and R 29 When R is a hydrocarbon group, the hydrocarbon group may be an aliphatic hydrocarbon group. 29 Z may be a monovalent organic group other than a hydrocarbon group, a hydrocarbon group having a ring structure, or an aromatic hydrocarbon group. 1 When R is -O-, W may be a monovalent organic group other than the group represented by WH when R is an alkyl ether. 26 ~R 28 When is a monovalent organic group, the monovalent organic group is R 25 The same examples given above are included.

[0061] In a group having an aromatic ring (for example, the above-mentioned aromatic hydrocarbon group), a monovalent substituent may be bonded to the aromatic ring. Examples of the monovalent substituent include a monovalent organic group, and examples of the monovalent organic group include a substituted or unsubstituted hydrocarbon group, a group represented by the formula: -R 61 -(W 1 -R 62 ) n -W 2 R 63 Examples of the group represented by the formula: -R 61 -(W 1 -R 62 ) n -W 2 R 63 The group represented by the formula (I) may be bonded to the para position of the benzene ring. 1 may be a divalent group such as -O-, -S-, -C(=O)- or -C(=O)O-, or may be -O-. 2 may be a divalent group such as -O-, -S-, -C(=O)- or -C(=O)O-, or may be -O-.

[0062] In the above monovalent organic group, R 61 is a covalent bond or a divalent organic group. The divalent organic group may be a divalent hydrocarbon group. The divalent hydrocarbon group may have 1 to 8 carbon atoms, 1 to 5 carbon atoms, or 1 to 3 carbon atoms. The hydrogen atoms bonded to the divalent hydrocarbon group may be substituted with a substituent such as a monovalent substituent (i.e., the divalent hydrocarbon group may be a substituted hydrocarbon group). Examples of the substituent include a halogen atom such as a fluorine atom. Specific examples of the divalent hydrocarbon group include a methylene group, an ethylene group, a 1,2-propylene group, a 1,3-propylene group, or a group in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine atoms, and may be a methylene group.

[0063] In the above monovalent organic group, R 62is a divalent organic group, and may be a divalent hydrocarbon group. The number of carbon atoms in the divalent hydrocarbon group may be 1 to 8, 1 to 5, or 1 to 3. The hydrogen atoms bonded to the divalent hydrocarbon group may be substituted with a substituent such as a monovalent substituent (i.e., the divalent hydrocarbon group may be a substituted hydrocarbon group). Examples of the substituent include a halogen atom such as a fluorine atom. Specific examples of the divalent hydrocarbon group include a methylene group, an ethylene group, a 1,2-propylene group, a 1,3-propylene group, or a group in which some or all of the hydrogen atoms in these groups are substituted with a halogen atom such as a fluorine atom, and may be an ethylene group. n may be 1 to 10, 1 to 5, or 1 to 3. n may be an integer or a rational number (for example, n is an average value over the structural unit (C) in the polymer (A) or (B)). R 62 When there are multiple, they may be different or identical.

[0064] In the above monovalent organic group, R 63 may be a hydrogen atom or a monovalent hydrocarbon group. The number of carbon atoms in the monovalent hydrocarbon group may be 1 to 8, 1 to 5, or 1 to 3. The hydrogen atom bonded to the monovalent hydrocarbon group may be substituted with a substituent such as a monovalent substituent (i.e., the monovalent hydrocarbon group may be a substituted hydrocarbon group). Examples of the substituent include a halogen atom such as a fluorine atom. Specific examples of the monovalent hydrocarbon group include a methyl group, an ethyl group, an isopropyl group, an n-propyl group, or groups in which some or all of the hydrogen atoms in these groups are substituted with halogen atoms such as fluorine atoms, and may be a methyl group.

[0065] When the polymer (A) contains the structural unit (C), the structural unit (C) may contain at least one type of structural unit derived from a monomer represented by the following formula (C1). [ka] (In the formula, m is 0 to 4, and n is 0 to 10.20 may be a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. The alkyl group may be a methyl group or an ethyl group, and may be a methyl group. In formula (C1), m may be 1 to 3, 1 to 2, or 1. m may be an integer or an average value across all structural units derived from the monomer represented by formula (C1) contained in polymer (A) or (B) (in this case, m is a rational number). In formula (C1), n ​​may be 1 to 4, or 1 to 3. n may be an integer or an average value across all structural units derived from the monomer represented by formula (C1) contained in polymer (A) or (B) (in this case, n is a rational number).

[0066] When the polymer (A) has a structural unit (C), R 26 and R 27 One of them is R 28 When the structural unit (C) forms a ring together with the structural unit (C2), the number of members of the ring may be 4 to 10, 4 to 8, or 5 to 7. The structural unit (C) may be the following structural unit (C2). [ka] (In formula (C2), X is an oxygen atom or -NR 24 - is a tertiary amino group represented by R 24 is a monovalent organic group, and R 25 and R 26 are each independently a hydrogen atom or a monovalent substituent.

[0067] In formula (C2), R 24 The number of carbon atoms in R may be 1 to 20, may be 1 to 15, or may be 2 to 10. 24 may be a hydrocarbon group or a fluorine-substituted hydrocarbon group, and may be an ethyl group, a 2,2,2-trifluoroethyl group, an n-dodecyl group, a cyclohexyl group, or a benzyl group.

[0068] The ratio of the structural unit (A) to all structural units contained in the polymer (A) may be from 0.2 to 0.95, from 0.2 to 0.8, from 0.3 to 0.7, or from 0.4 to 0.6.

[0069] The ratio of the structural unit (C) to all structural units contained in the polymer (A) may be 0.05 to 0.8, 0.2 to 0.8, 0.3 to 0.7, or 0.4 to 0.6. The ratio of the structural unit (C) to all structural units contained in the polymer (A) may be 0.8 or less, 0.7 or less, 0.6 or less, or 0.3 or less.

[0070] The total ratio of the structural unit (A) and the structural unit (C) to all structural units contained in the polymer (A) may be 0.5 or more, 0.6 or more, 0.7 or more, 0.8 or more, 0.9 or more, or 0.95 or more.

[0071] The content of the structural unit (A) relative to the total mass of the polymer (A) may be 25 to 95 mass %, may be 40 to 90 mass %, or may be 50 to 90 mass %.

[0072] The content of the structural unit (C) relative to the total mass of the polymer (A) may be 5 to 75 mass%, 10 to 60 mass%, or 10 to 50 mass%. The content of the structural unit (C) relative to the total mass of the polymer (A) may be 75 mass% or less, 60 mass% or less, 50 mass% or less, or 25 mass% or less.

[0073] The sum of the contents of the structural units (A) and (C) relative to the total mass of the polymer (A) may be 90 mass % or more, 95 mass % or more, or 98 mass % or more.

[0074] When the polymer (A) contains the structural unit (B), the molar ratio m of the structural unit (B) to all structural units contained in the polymer (A) may be 0.2 to 0.8, 0.25 to 0.75, 0.3 to 0.7, 0.35 to 0.65, or 0.4 to 0.6. The content of the structural unit (B) to the total mass of the polymer (A) may be more than 10 mass% and 95 mass% or less, 15 to 95 mass%, 20 to 80 mass%, 25 to 60 mass%, or 30 to 45 mass%.

[0075] The number average molecular weight (Mn) of the polymer (A) may be 5000 to 400000, 8000 to 200000, 10000 to 150000, or 10000 to 100000. The weight average molecular weight (Mw) of the polymer (A) may be 5000 to 600000, 10000 to 450000, 20000 to 200000, or 20000 to 100000. The molecular weight distribution (Mw / Mn) of the polymer (A) may be 1.0 to 5.0, 1.2 to 3.0, or 1.3 to 2.5. The number average molecular weight and weight average molecular weight of the polymer (A) can be measured, for example, by gel permeation chromatography.

[0076] The polymer (A) may be one that does not hydrolyze in air. The absence of hydrolysis is determined according to the following criteria. First, the solution obtained by dissolving polymer (A) in a deuterated solvent 1 After that, the solution is stored under air for 7 days (for example, at a temperature of 25° C.±10° C. and a humidity (which may be a relative humidity) of 65±20%), and then measured again. 1 A polymer is defined as "not hydrolyzed" when the ratio of anionic functional groups protonated by hydrolysis to the anionic functional groups converted to an alkali metal before storage is less than 10% by H-NMR measurement. The ratio of protonated anionic functional groups may be 5% or less, or may be 1% or less.

[0077] The content of polymer (A) in the electrolyte composition may be 1 to 80% by mass, may be 3 to 70% by mass, may be 5 to 60% by mass, or may be 10 to 40% by mass with respect to the total amount of the electrolyte composition part.

[0078] The production method of polymer (A) or (B) is not particularly limited. For example, it can be produced by radical addition polymerization of the corresponding monomer.

[0079] <Ionic compound> The ionic compound is not particularly limited, and examples include alkali metal salts and compounds having an organic cation. The electrolyte composition may contain at least one of an alkali metal salt and a compound having an organic cation.

[0080] When the Raman shift derived from the anion constituting the ionic compound in the Raman spectrum obtained by Raman spectroscopy for the ionic compound is A, and the Raman shift derived from the anion constituting the ionic compound in the Raman spectrum obtained by Raman spectroscopy for the electrolyte composition is B, the ionic compound is preferably a compound in which B ≤ A, and more preferably B < A. The fact that B < A means that the Raman shift of the ionic compound is shifted to the low wavenumber side (long wavelength side) in the electrolyte composition, which means that a so-called red-shift has occurred. The occurrence of a red-shift means that the anion part of the ionic compound corresponds to the weak interaction with an alkali metal ion (for example, Li + ). Therefore, by using an ionic compound that causes the above red-shift in the electrolyte composition, the movement of alkali metal ions can be made easier.

[0081] The difference between B and A (the value of AB) is 0.0 or more, but may be 0.1 or more, 0.2 or more, or 0.3 or more. The value of AB may also be 20.0 or less, 15.0 or less, 10.0 or less, 9.5 or less, 9.0 or less, 7.0 or less, 5.0 or less, 4.0 or less, 3.0 or less, 2.0 or less, 1.0 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, or 0.4 or less.

[0082] The Raman shift in this specification means a value determined from a Raman spectrum obtained by performing Raman spectroscopy using a laser with a wavelength of 785 nm. For example, a Raman spectrometer (apparatus name: DXR3) manufactured by Thermo Fisher Scientific can be used for Raman spectroscopy. The above Raman shift A and Raman shift B are peaks corresponding to deformation vibrations of an ionic compound. The above Raman shift corresponds to the anion portion in an ionic compound, and the anion is PF6 - In the case of FPF, it corresponds to the bending vibration, and in the case of TFSI - or FSI - In the case of , it corresponds to the bending vibration of SNS, and OTf - In the case of N(CN)2, it corresponds to the bending vibration of CSO. - In this case, it corresponds to the bending vibration of CNC.

[0083] Examples of alkali metal salts include MF, MCl, MBr, MI, MNO3, MClO4, MPF6, MBF4, M2SO4, and M[(C h F 2h+1 )SO3](h is 0-3), M[(C h F 2h+1 )SO2]2N(h is 0-3), M{[(C h F 2h+1 )SO2]N(C i F 2i+1)SO2]} (h, i are 0 to 3), MBOB (BOB is bisoxalatoborate), etc. One or more kinds of alkali metal salts may be used. M is not particularly limited as long as it is an alkali metal, and may contain lithium, sodium or potassium, may contain lithium or sodium, or may contain potassium. The alkali metal element contained in the alkali metal salt may be the same alkali metal element as the alkali metal element contained in the structural unit (A).

[0084] The content of the alkali metal salt in the electrolyte composition may be 0.1 to 200 mol %, 2.5 to 150 mol %, 5 to 100 mol %, or 10 to 60 mol %, calculated as the alkali metal ion contained in the alkali metal salt, relative to the total amount of the structural units (A) contained in the polymer (A).

[0085] The compound having an organic cation may be an ionic liquid. The formal charge of the organic cation may be monovalent, but may also be divalent or higher. Examples of the compound having an organic cation include imidazolium salts, pyrrolidinium salts, piperidinium salts, pyridinium salts, quaternary ammonium salts, and quaternary phosphonium salts. The anion of the compound having an organic cation is not particularly limited, and may be, for example, Cl. - , Br - , I - , ClO4 - , PF6 - , BF4 - , CF3SO3 - , (FSO2)2N - , (CF3SO2)2N - , (C r F 2r+1 SO2)2N - (r is an integer of 2 or more), HSO3 - From the viewpoint of electrochemical stability, PF6 - , BF4 - , CF3SO3 - , (FSO2)2N - , (CF3SO2)2N - Or (C m F 2m+1SO2)2N - (FSO2)2N - or (CF3SO2)2N - (CF3SO2)2N - The ionic liquid may be liquid at 25°C.

[0086] Examples of the pyrrolidinium cation contained in the pyrrolidinium salt include the following. [ka] In the formula, R 41 and R 42 are each independently a monovalent organic group, and the organic group preferably has 1 to 15 carbon atoms. The monovalent organic group is preferably an alkyl group having 1 to 15 carbon atoms, such as a butyl group, or a group represented by the formula: -A 1 -O-(A 2 -O) k -A 3 A group represented by 1 is an alkylene group having 1 or 2 carbon atoms, A 2 is an alkylene group having 2 or 3 carbon atoms, A 3 is an alkyl group having 1 to 3 carbon atoms, and k is 0 to 3. Formula:-A 1 -O-(A 2 -O) k -A 3 The group represented by the formula is preferably a group having 1 to 10 carbon atoms, and more preferably a -CH3OCH2CH2OCH3 group or a -CH2CH2-O-CH3 group. 41 R is an alkyl group having 1 to 3 carbon atoms and may be a methyl group. 41 and R 42 may be the same or different. The hydrogen bonded to the carbon atom constituting the pyrrolidine ring may be substituted with a substituent.

[0087] Examples of the piperidinium cation contained in the piperidinium salt include the following. [ka] In the formula, R 43 and R 44 are each independently a monovalent organic group, and the organic group preferably has 1 to 15 carbon atoms. The monovalent organic group is preferably an alkyl group having 1 to 15 carbon atoms or a group of the formula: -A 1 -O-(A 2 -O) k -A 3 A group represented by 1 is an alkylene group having 1 or 2 carbon atoms, A 2 is an alkylene group having 2 or 3 carbon atoms, A 3 is an alkyl group having 1 to 3 carbon atoms, and k is 0 to 3. R 44 The alkyl group of the formula: -A is more preferably an alkyl group having 2 to 6 carbon atoms, such as a butyl group. 1 -O-(A 2 -O) k -A 3 The group represented by the formula is preferably a group having 1 to 10 carbon atoms, and more preferably a -CH3OCH2CH2OCH3 group or a -CH2CH2-O-CH3 group. 43 R is an alkyl group having 1 to 3 carbon atoms and may be a methyl group. 43 and R 44 may be the same or different. The hydrogen bonded to the carbon atom constituting the piperidine ring may be substituted with a substituent.

[0088] Examples of the imidazolium cation contained in the imidazolium salt include the following. [ka] In the formula, R 46 and R 47are each independently a monovalent organic group, and the organic group preferably has 1 to 15 carbon atoms. The monovalent organic group is preferably an alkyl group having 1 to 15 carbon atoms or a group of the formula: -A 1 -O-(A 2 -O) k -A 3 A group represented by 1 is an alkylene group having 1 or 2 carbon atoms, A 2 is an alkylene group having 2 or 3 carbon atoms, A 3 is an alkyl group having 1 to 3 carbon atoms, and k is 0 to 3. R 47 The alkyl group of the formula: -A is preferably an alkyl group having 2 to 6 carbon atoms, such as a butyl group. 1 -O-(A 2 -O) k -A 3 The group represented by the formula is preferably a group having 1 to 10 carbon atoms, and more preferably a -CH3OCH2CH2OCH3 group or a -CH2CH2-O-CH3 group. 46 R is an alkyl group having 1 to 3 carbon atoms and may be a methyl group. 46 and R 47 may be the same or different. The hydrogen bonded to the carbon atom constituting the imidazole ring may be substituted with a substituent.

[0089] Examples of the ammonium cation contained in the quaternary ammonium salt include the following. [ka] In the formula, R 51 ~R 54 are each independently a monovalent organic group, and the organic group preferably has 1 to 15 carbon atoms. The monovalent organic group is preferably an alkyl group having 1 to 15 carbon atoms or a group of the formula: -A 1 -O-(A 2 -O) k -A 3 A group represented by 1is an alkylene group having 1 or 2 carbon atoms, A 2 is an alkylene group having 2 or 3 carbon atoms, A 3 is an alkyl group having 1 to 3 carbon atoms, and k is an integer of 0 to 3. 51 ~R 54 may all be the same, or may be two or more different groups. For example, R 51 is an alkyl group having 1 to 10 carbon atoms, and R 52 ~R 54 is preferably an alkyl group having 1 to 3 carbon atoms, and R 51 is an alkyl group having 3 to 8 carbon atoms, such as a butyl group, and R 52 ~R 54 It is more preferable that the formula: -A is a methyl group or an ethyl group. 1 -O-(A 2 -O) k -A 3 The group represented by the formula is preferably a group having 1 to 10 carbon atoms, and more preferably a -CH3OCH2CH2OCH3 group or a -CH2CH2-O-CH3 group.

[0090] Examples of the phosphonium cation contained in the quaternary phosphonium salt include the following. [ka] In the formula, R 56 ~R 59 are each independently a monovalent organic group, and the organic group preferably has 1 to 15 carbon atoms. The monovalent organic group is preferably an alkyl group having 1 to 15 carbon atoms or a group of the formula: -A 1 -O-(A 2 -O) k -A 3 A group represented by 1 is an alkylene group having 1 or 2 carbon atoms, A 2 is an alkylene group having 2 or 3 carbon atoms, A 3 is an alkyl group having 1 to 3 carbon atoms, and k is an integer of 0 to 3.56 ~R 59 may all be the same, or may be two or more different groups. For example, R 56 is an alkyl group having 1 to 10 carbon atoms, and R 57 ~R 59 is preferably an alkyl group having 1 to 3 carbon atoms, and R 56 is an alkyl group having 3 to 8 carbon atoms, such as a pentyl group, and R 57 ~R 59 is more preferably a methyl group or an ethyl group.

[0091] The compound having an organic cation may include one or more organic cations selected from the group consisting of 1-ethyl-1-methylpyrrolidinium cation, 1-n-propyl-1-methylpyrrolidinium cation, 1-n-butyl-1-methylpyrrolidinium cation, 1-n-propyl-1-methylpiperidinium cation, 1-n-butyl-1-methylpiperidinium cation, 1-ethyl-3-methylimidazolium cation, butyltrimethylammonium cation, and triethylpentylphosphonium cation. The compound having an organic cation may include one or more anions selected from the group consisting of hexafluorophosphate anion, bis(fluorosulfonyl)imide anion, bis(trifluoromethanesulfonyl)imide anion, and trifluoromethanesulfonate anion.

[0092] Specific examples of compounds having an organic cation include 1-(2-methoxyethoxymethyl)-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-n-butyl-1-methylpyrrolidinium hexafluorophosphate, 1-n-propyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide, 1-n-propyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, 1-n-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide, 1-ethyl-1-methylpyrrolidinium bis(trifluoromethane ... diphenyl bis(trifluoromethylsulfonyl)imide, 1-n-propyl-1-methylpiperidinium bis(fluorosulfonyl)imide, 1-n-propyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, 1-n-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide, 1-n-butyl-1-methylpyrrolidinium trifluoromethanesulfonic acid, 1-n-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide, triethyl-n-pentylphosphonium bis(trifluoromethanesulfonyl)imide, n-butyltrimethylammonium bis(trifluoromethanesulfonyl)imide, and the like.

[0093] The content of the compound having an organic cation in the electrolyte composition may be 5 to 400 parts by mol, 10 to 300 parts by mol, or 20 to 250 parts by mol, relative to 100 parts by mol of the structural unit (A) contained in the polymer (A).

[0094] <Non-ionic organic solvent> The nonionic organic solvent may be an aprotic solvent. The nonionic organic solvent may contain one or more organic solvents selected from the group consisting of carbonate-based solvents, ether-based solvents, fluorine-based solvents, nitrile-based solvents, lactone-based solvents, phosphate-based solvents, and sulfone-based solvents, and may contain a phosphate ester. The nonionic organic solvent may contain one or more solvents selected from the group consisting of carbonate-based solvents, ether-based solvents, fluorine-based solvents, nitrile-based solvents, and phosphate ester-based solvents, and may contain a carbonate-based solvent. In the electrolyte composition, the polymer (A) may be swollen by the organic solvent.

[0095] Examples of carbonate solvents include linear carbonates such as dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate; and cyclic carbonates such as ethylene carbonate, propylene carbonate, butylene carbonate, and vinylene carbonate. The organic solvent may be a mixed solvent containing two or more types of carbonate solvents, a mixed solvent containing one or more types of cyclic carbonate solvents and one or more types of linear carbonate solvents, or a mixed solvent containing two or more types of cyclic carbonate solvents.

[0096] Examples of the ether solvent include cyclic ethers such as tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, and 1,3-dioxolane; and chain ethers such as 1,2-diethoxyethane and ethoxymethoxyethane.

[0097] Examples of the fluorine-based solvent include hydrofluorocarbons such as perfluorooctane; hydrofluoroethers such as methyl nonafluorobutyl ether and ethyl nonafluorobutyl ether; hydrofluoroolefins such as 1,3,3,3-tetrafluoropropene; and 2,2,2-trifluoro-N,N-dimethylacetamide.

[0098] Examples of the phosphate ester include trimethyl phosphate (TMP), triethyl phosphate (TEP), and tris(2,2,2-trifluoroethyl) phosphate (TFEP).

[0099] Examples of the nitrile solvent include acetonitrile, succinonitrile, etc. Examples of the lactone solvent include γ-butyrolactone, etc.

[0100] Other examples of non-ionic organic solvents include sulfone-based solvents such as sulfolane and 3-methylsulfolane, solvents having a sulfonyl group such as dimethylsulfoxide (DMSO), amide-based solvents such as dimethylformamide (DMF) and dimethylacetamide (DMA), organic solvents having a carbonyl group such as acetone (referring to carbonyl compounds other than amide compounds such as -C(=O)-, esters, ketones, and aldehydes), and nitrogen-containing aromatic compounds such as pyridine (compounds containing nitrogen as a ring member of an aromatic ring, which may be either a monocyclic or condensed ring system). The organic solvent may be used alone or as a mixed solvent containing two or more organic solvents.

[0101] The content of the organic solvent in the electrolyte composition may be 10 to 1000 parts by mass, 50 to 800 parts by mass, 100 to 600 parts by mass, 150 to 500 parts by mass, or 200 to 400 parts by mass, relative to 100 parts by mass of the polymer (A) contained in the electrolyte composition.

[0102] The transport number of the alkali metal ion of the electrolyte composition may be 0.5 or more, 0.6 or more, or 0.7 or more. The transport number may be a transport number measured at room temperature (25° C.).

[0103] The electrolyte composition may further contain other resins such as fluorine-based resins (resins other than polymers (A) and (B) such as binder resins), fabrics such as nonwoven fabrics, porous materials, viscosity modifiers, anion receptors, and the like. The electrolyte composition may contain a resin having a carbon chain as the main chain as the fluorine-based resin. The carbon chain may be formed by radical polymerization of an ethylenically unsaturated group. Examples of the fluorine-based resin include poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and polyvinylidene fluoride (PVDF). The porous material may be a resin-made porous material. Specific examples include a porous polyolefin membrane and a porous ceramic membrane. The content of the other resin may be 1 to 200 parts by mass, 5 to 150 parts by mass, 10 to 100 parts by mass, or 10 to 80 parts by mass relative to 100 parts by mass of the polymer (A).

[0104] The anion receptor is not particularly limited. The formula weight (molecular weight) of the anion receptor may be 1000 or less, 800 or less, or 500 or less. The anion receptor may have Lewis acidity. In this case, the anion receptor can capture the anion by accepting the unshared electron pair of the anion and forming an acid-base complex. Such a compound may include a compound having an electron-deficient atom. The electron-deficient atom refers to an atom that is covalently bonded to another atom but has less than 8 electrons in the outermost shell. The electron-deficient atom may be an atom belonging to Group 13 of the periodic table, and more specifically, may be at least one of an aluminum atom and a boron atom, or may be a boron atom.

[0105] The anion receptor having a boron atom includes a boron compound that functions as a Lewis acid, and may be diborane or a compound represented by the following chemical formulas IA to IE.

[0106] [ka]

[0107] In formulas IA and ID, R 31 and R 33 are each a halogen atom or a monovalent organic group. The halogen atom may be a fluorine atom or a chlorine atom, or may be a fluorine atom. The number of carbon atoms in the monovalent organic group may be 1 to 20, 1 to 15, 2 to 10, or 2 to 6. Here, the monovalent organic group is bonded to the boron atom (B) in formula IA or ID via a carbon atom in the monovalent organic group. The monovalent organic group may be a hydrocarbon group or a halogen-substituted hydrocarbon group, and the halogen-substituted hydrocarbon group may be a partially or fully fluorinated hydrocarbon group. In one molecule, a plurality of R 31 and R 33 may be different from each other or may all be the same.

[0108] In formulas IB and IE, R 32 and R 34 are each a hydrogen atom or a monovalent organic group. The halogen atom may be a fluorine atom or a chlorine atom, or may be a fluorine atom. The number of carbon atoms in the monovalent organic group may be 1 to 20, 1 to 15, 2 to 10, or 2 to 6. Here, the monovalent organic group is bonded to the oxygen atom (O) in formula IB or IE via a carbon atom in the monovalent organic group. The monovalent organic group may be a hydrocarbon group or a halogen-substituted hydrocarbon group, and the halogen-substituted hydrocarbon group may be a partially or fully fluorinated hydrocarbon group. In one molecule, a plurality of R 32 and R 34 may be different from each other or may all be the same.

[0109] In the formula IC, R 35 is a divalent organic group, Z 2 is a covalent bond or an oxygen atom. The number of carbon atoms in the divalent organic group may be 1 to 15, 2 to 10, or 3 to 8. 35 , two Z's 2and the boron atom (B) form a ring, and the ring may have 4 to 8 ring members, or may have 5 or 6 ring members. 2 When is an oxygen atom, the divalent organic group is connected to Z in formula IC by a carbon atom contained in the divalent organic group. 2 is bonded to Z 2 When Z is a covalent bond, the divalent organic group is bonded to the boron atom (B) in formula IC through a carbon atom contained in the divalent organic group. The divalent organic group may be a hydrocarbon group or a halogen-substituted hydrocarbon group, and the halogen-substituted hydrocarbon group may be a partially or fully fluorinated hydrocarbon group. 2 may be different from each other or may all be the same.

[0110] In the formula IC, R 36 is a hydrogen atom or a monovalent organic group. The monovalent organic group may be a group that bonds to the boron atom (B) in formula IC through a carbon atom of the monovalent organic group, but -OR 37 R may be a group represented by the formula: 37 R is a hydrogen atom or a monovalent organic group. 37 The monovalent organic group represented by the formula (I) is -OR 37 It is bonded to the oxygen atom of R. 36 or R 37 The number of carbon atoms in the monovalent organic group as may be 1 to 20, 1 to 15, 2 to 10, or 2 to 6. Here, the monovalent organic group is bonded to the boron atom (B) in formula IA via a carbon atom in the monovalent organic group. The monovalent organic group may be a hydrocarbon group or a halogen-substituted hydrocarbon group, and the halogen-substituted hydrocarbon group may be a partially or fully fluorinated hydrocarbon group.

[0111] Specific examples of boron compounds include diborane, boron trifluoride, boric acid, boroxine, trimethylborane, triethylborane, tri-n-propylborane, triisopropylborane, triphenylborane, trimethylborate, triethylborate, triphenylborate, tri-n-propylborate, triisopropylborate, 2-methoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, and 2-ethoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. Examples of the boron compounds include orphan, 2,4,6-trimethylboroxine, 2,4,6-triethylboroxine, 2,4,6-trivinylboroxine, 2,4,6-trimethoxyboroxine, 2,4,6-trimethoxyboroxine, and triphenylboroxine; and halogen-substituted hydrocarbon groups such as tris(2,2,2-trifluoroethyl)borate, 2,4,6-tris(4-fluorophenyl)boroxine, and 2,4,6-tris(3,4,5-trifluorophenyl)boroxine.

[0112] The anion receptor having an aluminum atom includes aluminum compounds that function as Lewis acids and have the formula AlX 1 3(X 1 is a halogen atom, which may be a fluorine atom; 35 )3(R 35 is a hydrocarbon group, which may be an alkyl group.

[0113] The anion receptor may also be an azaether. An azaether is an ether compound in which the -O- is replaced by -NR E - (where R E is a hydrogen atom or an organic group). The azaether may be either a linear azaether or a cyclic azaether. The azaether may have an electron-withdrawing group, for example, in the hydrocarbon portion.

[0114] The content of the anion receptor in the electrolyte composition may be 10 to 200 parts by mass, 30 to 180 parts by mass, 50 to 150 parts by mass, or 80 to 130 parts by mass relative to 100 parts by mass of the polymer (A).

[0115] The method for producing the electrolyte composition is not particularly limited, but the electrolyte composition can be obtained by preparing a solution containing the polymer (A) and an ionic compound, drying the solution, and then adding an organic solvent. In this case, the electrolyte composition may be used as a dried film, or may be impregnated into a porous material such as a separator (such as a resin film) and then dried.

[0116] The electrolyte composition of the present embodiment can be used as a composition for forming an electrolyte for a battery, a capacitor, or the like. That is, the electrolyte of the battery or the like of the present embodiment may contain the electrolyte composition. Examples of the battery include a battery that performs charging and discharging by the movement of alkali metal ions, such as a lithium ion battery and a sodium ion battery. The battery may be a primary battery, a secondary battery, or a solid battery. The electrolyte composition of the present embodiment may be used as an electrode material, and may be contained in at least one of the positive electrode and the negative electrode.

[0117] The battery of this embodiment includes a positive electrode, a negative electrode, and an electrolyte disposed between the positive electrode and the negative electrode. The positive electrode may be a layer including a positive electrode material formed on a current collector. The negative electrode may be a layer including a negative electrode material formed on a current collector. Hereinafter, a lithium ion battery will be taken as an example for explanation.

[0118] The negative electrode of the lithium ion battery is not particularly limited, and may contain a negative electrode active material and, if necessary, a conductive assistant, a binder, etc. Examples of the negative electrode active material include simple elements such as Li, Si, P, Sn, Si-Mn, Si-Co, Si-Ni, In, and Au, alloys or composites containing these elements, carbon materials such as graphite, substances in which lithium ions are inserted between layers of the carbon material, and oxides containing titanium.

[0119] The positive electrode of the lithium ion battery is not particularly limited, and may contain a positive electrode active material and, if necessary, a conductive assistant, a binder, etc. The positive electrode active material is not particularly limited, and may be, for example, a lithium composite metal oxide containing lithium and a transition metal element. The transition metal element may be at least one selected from the group consisting of V, Cr, Mn, Fe, Co, Ni, Cu, and Al, and may contain Ni. Examples of the lithium composite metal oxide include LiCoO2, LiNiO2, LiMn2O4, LiNi 0.5 Mn 1.5 O4, Li2MnO3, LiNi x Mn y Co 1-x-y O2[0 <x+y<1])、LiNi x Co y Al 1-x-y O2[0 <x+y<1])、LiCr 0.5 Mn 0.5 Examples of the positive electrode active material include O2, LiFePO4, Li2FeP2O7, LiMnPO4, LiFeBO3, Li3V2(PO4)3, Li2CuO2, Li2FeSiO4, and Li2MnSiO4. When the positive electrode active material contains an alkali metal element other than Li, specific examples thereof include those in which Li in the above specific examples is replaced with another alkali metal.

[0120] The negative electrode (negative electrode material) and the positive electrode (cathode material) of this embodiment may further contain a solid electrolyte material, a binding resin (binder), a conductive assistant, and the like.

[0121] The battery may have a separator. The separator may be a porous material, such as a porous resin material. Specific examples of the separator include a porous polyolefin membrane and a porous ceramic membrane. EXAMPLES

[0122] <Production of copolymer> A lithiated carboxyl group-containing copolymer was prepared by the following method. Saccharin methacrylamide (SacM) (1.8848 g, 7.5 mmol), styrene (St) (0.86 mL, 7.5 mmol), tetralin (0.15 mL) and azobisisobutyronitrile (24.7 mg, 0.15 mmol) were dissolved in a mixed solvent of dioxane and acetonitrile (dioxane:acetonitrile = 1:1 (volume ratio)) (12.1 mL) and stirred at 60 ° C for 24 hours to obtain a solution of a copolymer of saccharin methacrylamide and styrene (raw copolymer). Next, 25 mM phenothiazine in 1,4-dioxane (45.0 mL, 1.13 mmol) and 100 equivalents of water were added to the resulting polymerization solution, and the mixture was stirred overnight. As a result, the structural units derived from saccharin methacrylamide in the raw copolymer were hydrolyzed, and the amide bonds containing saccharin moieties were converted to -COOH groups (i.e., the structural units derived from saccharin methacrylamide were converted to methacrylic acid (MAA) units), resulting in the production of a -COOH group-containing copolymer (0.61 g). The composition ratio of the structural units in the polymer was MAA:St=48:52 (molar ratio). The composition ratio was determined by dissolving the polymer in deuterated dimethyl sulfoxide and 1 It was calculated by measuring the H-NMR spectrum. Then, the -COOH group-containing copolymer (0.61 g, 3.21 mmol) was dissolved in dimethylformamide (12 mL) to obtain a solution. 2.5 equivalents of LiOH (449.1 mg, 18.82 mmol) were added to the solution relative to the amount of SacM initially charged when producing the raw copolymer, and the mixture was stirred at room temperature (25°C) for 3 days. As a result, a copolymer in which the -COOH group of the -COOH group-containing copolymer was converted to -COOLi (lithiated carboxyl group-containing copolymer) was obtained (0.43 g). The solution obtained by dissolving the obtained polymer in deuterated DMSO solvent 1 When H-NMH was measured, the peak due to the -COOH group, which is expected to be observed around 12 ppm, was not confirmed. After leaving this solution in the atmosphere at room temperature for 7 days, 1H-NMH was measured, but no peak derived from -COOH groups was confirmed. It was determined that Polymer 1 was not hydrolyzed in air.

[0123] (Examples 1 to 9 and Comparative Example 1) A polymer solution was prepared by dissolving 100 parts by mass of the lithium carboxyl group-containing copolymer, 50 parts by mass of PVdF-HFP, and the ionic compound shown in Table 2 in dimethylformamide. This solution was impregnated onto a polyethylene separator, and then dried under reduced pressure at 80°C to obtain a composite membrane. An organic solvent (a mixed solvent of ethylene carbonate and propylene carbonate (volume ratio 1:1)) was added to this composite membrane in an amount twice the mass of the composite membrane minus the weight of the PE separator, to obtain an electrolyte composition.

[0124] <Measurement of lithium ion transport number> The lithium ion transport number of the electrolyte composition of each of the Examples and Comparative Examples was measured by the following method. The results are shown in Table 2. In a glove box under a dry argon atmosphere, an evaluation cell of a coin-type lithium battery CR2032 was assembled. Specifically, each layer was laminated in the evaluation cell in the following order to prepare a test laminate. (Lithium / Electrolyte composition / Lithium) The lithium ion transport number measurement method is introduced in Polymer, 28, 2324 (1987). That is, 10 mV is applied to the test laminate at room temperature (25° C.), and the initial current value (I0) and the steady-state current value (I ss ) was measured, and the interfacial resistance measured value R0 before the voltage application and the interfacial resistance measured value R after the voltage application were also measured. SS The lithium ion transport number (t Li+ ) was calculated, where V is the applied voltage. t Li+ =I ss (V-I0R0) / I0(VI SS R SS )

[0125] <Measurement of maximum DC current density> In a glove box under a dry argon atmosphere, an evaluation cell of a coin-type battery CR2032 was assembled. Specifically, each layer was laminated in the evaluation cell in the following order to prepare a test laminate. (Lithium / Electrolyte composition / Lithium) The evaluation cell was subjected to alternating currents of 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, and 2000 μA / cm in the positive and negative directions. 2 A constant current test was carried out in which current densities of 10 and 11 were applied in this order for 10 cycles each, and the test was terminated when the voltage reached 2V. The maximum current density that could be applied before reaching 2V was defined as the maximum DC current density, and the voltage value at that time was determined. The results are shown in Table 2. Figures 1 and 2 are diagrams showing the results of measuring the maximum DC current density using the electrolyte compositions of Example 4 and Comparative Example 1, respectively. In Figures 1 and 2, the dark curves show the change in voltage (vertical axis on the left), and the light curves show the change in current (vertical axis on the right). As shown in the boxed area in Figure 2, the overvoltage became too large to carry out the test halfway through, and no DC current flowed.

[0126] <Measurement of ionic conductivity> In a glove box under a dry argon atmosphere, an evaluation cell of a coin-type battery CR2032 was assembled. Specifically, each layer was laminated in the evaluation cell in the following order to prepare a test laminate. (Stainless steel plate / electrolyte composition / stainless steel plate) Using an impedance measuring device, measurements are taken at 25°C, in the frequency range of 0.1Hz to 1MHz, and at an applied voltage of 10mV (vs. open circuit voltage). Ionic conductivity σ can be calculated using the following formula. σ (S cm -1 )=t(cm) / (R(Ω)×A(cm 2 )) In the formula, R represents the impedance value, A represents the area of ​​the sample, and t represents the thickness of the sample. The results are shown in Table 2.

[0127] <Measurement of activation energy> Ion conductivity measurements using the above evaluation cell were also performed at 30, 40, 50, 60, and 70°C to measure the change in ion conductivity versus temperature. The activation energy was calculated from the slope of a graph of the common logarithm of ion conductivity versus the reciprocal of temperature using the Arrhenius equation (logk=logA-Ea / RT, k: reaction rate constant, A: frequency factor, Ea: activation energy, R: gas constant, T: absolute temperature). The results are shown in Table 2.

[0128] The abbreviations in Table 2 are as follows: P 14 FSI: 1-n-butyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide P 14 TFSI: 1-n-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P 12 TFSI: 1-ethyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide

[0129] <Raman spectrum measurement of ionic compounds> Representative ionic compounds and electrolyte compositions used in the examples and comparative examples were subjected to Raman spectroscopy. In the obtained Raman spectra, deformation vibrations of the anion moiety were observed, and the Raman shift values ​​were determined. 14 FSI was used, and in Example 8, P 14 Since TFSI is used, the anion part is FSI - and TFSI - The Raman shift of the bending vibration of SNS was observed. The results are shown in Table 3.

[0130] [Table 2]

[0131] [Table 3]

Claims

1. a polymer (A) having an anionic functional group and an alkali metal ion as a counter cation of the anionic functional group, wherein the energy of dissociation between the lithium ion and the anionic functional group is 150 kcal / mol or more; an ionic compound; a non-ionic organic solvent.

2. 2. The electrolyte composition according to claim 1, wherein the alkali metal ion has a transport number of 0.5 or more at 25°C.

3. 3. The electrolyte composition according to claim 1, wherein the alkali metal ions comprise lithium ions or sodium ions.

4. 3. The electrolyte composition according to claim 1, wherein the nonionic organic solvent comprises one or more solvents selected from the group consisting of carbonate-based solvents, ether-based solvents, fluorine-based solvents, nitrile-based solvents, lactone-based solvents, phosphate ester-based solvents, and sulfone-based solvents.

5. 3. The electrolyte composition according to claim 1, wherein the anionic functional group comprises at least one group selected from the group consisting of an alkali metal substituted sulfonic acid group and an alkali metal substituted carboxylic acid group.

6. 3. The electrolyte composition according to claim 1, wherein the polymer (A) does not hydrolyze in air.

7. A battery comprising the electrolyte composition of claim 1 or 2.

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