Electrochemical device mixture, electrochemical device mixture sheet, electrochemical device, and method for manufacturing electrochemical device mixture sheet

Abstract

The purpose of the present disclosure is to provide an electrochemical device mixture, an electrochemical device mixture sheet, an electrochemical device, and a method for manufacturing the electrochemical device mixture sheet, which make it possible to improve sheet strength. The present disclosure pertains to an electrochemical device mixture that contains a fluoropolyether, a fibril resin, and an electrochemical device material.

Description

Mixture for electrochemical device, mix sheet for electrochemical device, electrochemical device, and method for manufacturing mix sheet for electrochemical device

[0001] The present disclosure relates to a mixture for an electrochemical device, a mixture sheet for an electrochemical device, an electrochemical device, and a method for producing a mixture sheet for an electrochemical device.

[0002] BACKGROUND ART With the recent trend toward lighter and smaller electrical appliances, the development of electrochemical devices such as lithium ion secondary batteries with high energy density has been progressing.

[0003] As technologies relating to electrochemical devices, Patent Document 1 discloses an electrode for a secondary battery using a powdered active material, a conductive material, and a fluorine-containing polymer resin, and Patent Document 2 discloses a self-supporting solid composite electrolyte membrane using solid ion-conductive inorganic particles and a tetrafluoroethylene (co)polymer.

[0004] JP 2007-026984 A JP 2022-546129 A

[0005] An object of the present disclosure is to provide a mixture for an electrochemical device, a mixture sheet for an electrochemical device, an electrochemical device, and a method for producing a mixture sheet for an electrochemical device, which are capable of improving sheet strength.

[0006] The present disclosure (1) is a mixture for an electrochemical device, which contains a fluoropolyether, a fibrillar resin, and an electrochemical device material.

[0007] The present disclosure (2) is the mixture for electrochemical devices according to the present disclosure (1), wherein the fluoropolyether is at least one of the fluoropolyethers represented by the following formulas (1) to (4): (1) R １ -O-Ra １ -Rb １ -O-Ra １ -R １ (2) R ２ -Rb ２ -O-Ra ２ -Rb ２ -R ２ (3) R ３ -Rb ３ -O-Ra ３ -R ３ (4) R４ -Rb ４ -R ４ (In the formula, Ra １ ~Ra ３ are each independently a polyoxyalkylene group containing 4 to 50 oxyalkylene units and not containing fluorine, １ ~Ra ３ Each oxyalkylene unit is independently —CH ２ CH ２ O- or -CH ２ CH(J)O—, each J is independently an alkyl group or an aryl group, and Rb １ ~Rb ４ are each independently a fluoropolyether group represented by the following formula (5), １ ~R ３ are each independently a hydrogen atom, a hydroxyl group, a fluorine atom, an alkyl group having 1 to 3 carbon atoms, an aryl group, a carboxylic acid group, or a fluoroalkyl group having 1 to 3 carbon atoms, ４ are each independently a fluorine atom, a hydrogen atom, a hydroxyl group, an aldehyde group, a carboxylic acid group, an alkyl ester group having 1 to 10 carbon atoms, an amide group which may have a substituent, or an amino group which may have a substituent. １ -Rf-O-Rf ２ - (wherein, Rf １ and Rf ２ are each independently an alkylene group having 1 to 16 carbon atoms which may be substituted with a fluorine atom, and Rf is a divalent fluoropolyether group.

[0008] The present disclosure (3) is １ ~Ra ３ are each independently a polyoxyalkylene group represented by the following formula (Ra-I): —(CH ２ CH ２ O)r(CH ２ CH (CH ３ )O)s(CH ２ CH (CH ２ CH ３ )O)t(CH ２CH(Ph)O)u- (wherein r, s, t, and u each independently represent an integer of 0 or 1 or greater, and r+s+t+u is 4 to 50.)

[0009] The present disclosure (4) is １ ~Ra ３ The mixture for electrochemical devices according to the present disclosure (2) or (3), wherein the number average molecular weight of

[0010] The present disclosure (5) is the mixture for electrochemical devices according to any one of the present disclosures (2) to (4), in which each Rf is independently a fluoropolyether group represented by the following formula (Rf-I): Formula (Rf-I): -(OC ６ F １２ ) a-(OC ５ F １０ ) b-(OC ４ F ８ ) c-(OC ３ Rc ６ ) d-(OC ２ F ４ ) e-(OCF ２ )f- (In the formula, each Rc is independently a hydrogen atom, a fluorine atom, or a chlorine atom; each a, b, c, d, e, and f is independently an integer of 0 to 200; the sum of a, b, c, d, e, and f is 1 or more; the order of the repeating units assigned with a, b, c, d, e, or f is arbitrary; and when all Rc's are hydrogen atoms or chlorine atoms, at least one of a, b, c, e, and f is 1 or more.)

[0011] The present disclosure (6) is the mixture for electrochemical devices according to any one of the present disclosures (2) to (5), in which each Rf is independently a group represented by the following formula (Rf-II) or the following formula (Rf-I-II): Formula (Rf-II): -(OC ３ F ６ ) d-(OC ２ F ４ )e- (wherein d is an integer of 1 to 200, and e is 0 or 1) Formula (Rf-I-II): -(OC ４ F ８ ) c-(OC ３ F ６ ) d-(OC ２ F４ ) e-(OCF ２ )f- (In the formula, c and d each independently represent an integer of 0 to 30, e and f each independently represent an integer of 1 to 200, the sum of c, d, e and f is 2 or more, and the order of the repeating units assigned with c, d, e or f is arbitrary.)

[0012] The present disclosure (7) is １ ~R ３ are each independently a methyl group, an ethyl group, a trifluoromethyl group, or a pentafluoroethyl group.

[0013] The present disclosure (8) is the mixture for electrochemical devices according to any one of the present disclosures (1) to (7), in which the fibrillar resin is polytetrafluoroethylene.

[0014] The present disclosure (9) is the mixture for an electrochemical device according to any one of the present disclosures (1) to (8), in which the electrochemical device material is an electrode active material.

[0015] The present disclosure (10) is the mixture for electrochemical devices according to any one of the present disclosures (1) to (9), wherein the fluoropolyether is liquid at any temperature between 25°C and 80°C.

[0016] The present disclosure (11) is the mixture for electrochemical devices according to any one of the present disclosures (1) to (10), in which the content of the polyalkylene oxide represented by the following formula (6) is less than 20 mass %: １Ｂ -(OCHR １Ａ (CH ２ ) jCHR ２Ａ ) n-OR ２Ｂ (In the formula, R １Ａ and R ２Ａ are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, j is an integer of 0 or 1 or 2, and R １Ｂ and R ２Ｂ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and n is an integer of 5 to 1000.

[0017] The present disclosure (12) is a mixture for electrochemical devices according to any one of the present disclosures (1) to (11), which contains a conductive assistant.

[0018] The present disclosure (13) is a mixture sheet for electrochemical devices, including the mixture for electrochemical devices according to any one of the present disclosures (1) to (12).

[0019] The present disclosure (14) is an electrochemical device using the mixture sheet for electrochemical devices according to the present disclosure (13).

[0020] The present disclosure (15) is a method for producing a mixture sheet for electrochemical devices, the method comprising: a step (1) of mixing a fluoropolyether, a fibrillar resin, and an electrochemical device material; and a step (2) of rolling the mixture for electrochemical devices obtained in the step (1) into a sheet.

[0021] The present disclosure (16) is the manufacturing method according to the present disclosure (15), wherein the fibrillar resin is polytetrafluoroethylene.

[0022] According to the present disclosure, it is possible to provide a mixture for an electrochemical device, a mixture sheet for an electrochemical device, an electrochemical device, and a method for manufacturing a mixture sheet for an electrochemical device, which are capable of improving sheet strength.

[0023] The present disclosure will be specifically described below.

[0024] <Agent Mixture for Electrochemical Device> The present disclosure relates to an agent mixture for an electrochemical device, which contains a fluoropolyether, a fibrillar resin, and an electrochemical device material.

[0025] The composite for electrochemical devices of the present disclosure has the above-described configuration, and therefore can improve the strength of electrode sheets and solid electrolyte sheets. This is thought to be because kneading the fluoropolyether and the fibrillar resin improves the cohesion between the powders and promotes the generation of fibrils. Furthermore, the promotion of fibril generation makes it possible to reduce the amount of binder used and improve the energy density of the electrochemical device.

[0026] As the fluoropolyether, at least one of the compounds represented by the following formulas (1) to (4) can be suitably used. These compounds can enhance the effect of improving sheet strength, and further improve the initial discharge capacity and the amount of gas generated. This is because Rb １ ~Rb ４ This is thought to be because the compound of formula (1) to (3) exhibits good lubricity and improves packing density. １ ~Ra ３ The portion (1) R can also provide ionic conductivity. １ -O-Ra １ -Rb １ -O-Ra １ -R １ (2) R ２ -Rb ２ -O-Ra ２ -Rb ２ -R ２ (3) R ３ -Rb ３ -O-Ra ３ -R ３ (4) R ４ -Rb ４ -R ４ (In the formula, Ra １ ~Ra ３ are each independently a polyoxyalkylene group containing 4 to 50 oxyalkylene units and not containing fluorine, １ ~Ra ３ Each oxyalkylene unit is independently —CH ２ CH ２ O- or -CH ２ CH(J)O—, each J is independently an alkyl group or an aryl group, and Rb １ ~Rb ４ are each independently a fluoropolyether group represented by the following formula (5), １ ~R ３ are each independently a hydrogen atom, a hydroxyl group, a fluorine atom, an alkyl group having 1 to 3 carbon atoms, an aryl group, a carboxylic acid group, or a fluoroalkyl group having 1 to 3 carbon atoms, ４are each independently a fluorine atom, a hydrogen atom, a hydroxyl group, an aldehyde group, a carboxylic acid group, an alkyl ester group having 1 to 10 carbon atoms, an amide group which may have a substituent, or an amino group which may have a substituent. １ -Rf-O-Rf ２ - (wherein, Rf １ and Rf ２ are each independently an alkylene group having 1 to 16 carbon atoms which may be substituted with a fluorine atom, and Rf is a divalent fluoropolyether group.

[0027] Ra １ ~Ra ３ The oxyalkylene unit is -CH ２ In the case of CH(J)O-, the alkyl group for J may be linear or branched, but is preferably linear. The alkyl group for J preferably has 1 to 3 carbon atoms. Examples of the aryl group for J include a phenyl group, a 4-nitrophenyl group, a 4-acetylaminophenyl group, and a 4-methanesulfonylphenyl group.

[0028] Ra １ ~Ra ３ are each independently a polyoxyalkylene group represented by the following formula (Ra-I): (Ra-I): —(CH ２ CH ２ O)r-(CH ２ CH (CH ３ )O)s-(CH ２ CH (CH ２ CH ３ )O)t-(CH ２ CH(Ph)O)u- (wherein r, s, t, and u each independently represent an integer of 0 or 1 or greater, and r+s+t+u is 4 to 50.)

[0029] In the above formula (Ra-I), r is preferably 1 or more, more preferably 2 or more, and preferably 30 or less, more preferably 20 or less. s, t, and u are preferably 10 or less, more preferably 5 or less, and even more preferably 0. r+s+t+u is preferably 1 or more, more preferably 2 or more, and preferably 20 or less, more preferably 10 or less.

[0030] Ra １ ~Ra ３ The number average molecular weight of the polymer is preferably 40 or more, more preferably 100 or more, and is preferably 4000 or less, more preferably 1000 or less. １ ~Ra ３ The number average molecular weight of １ This is a value measured by H-NMR.

[0031] Rb １ ~Rb ４ In the formula (5), Rf １ and Rf ２ The alkylene group of Rf may be linear or branched, but is preferably linear. １ and Rf ２ The alkylene group of Rf is preferably a fluorine-substituted alkylene group substituted with a fluorine atom. １ and Rf ２ The alkylene group preferably has 1 to 3 carbon atoms.

[0032] Rb １ ~Rb ４ In the above formula (5), Rf may have a ring structure.

[0033] Rb １ ~Rb ４ In the formula (5), Rf is preferably a fluoropolyether group represented by the following formula (Rf-I): Formula (Rf-I): -(OC ６ F １２ ) a-(OC ５ F １０ ) b-(OC ４ F ８ ) c-(OC ３ Rc６ ) d-(OC ２ F ４ ) e-(OCF ２ )f- (In the formula, each Rc is independently a hydrogen atom, a fluorine atom, or a chlorine atom; each a, b, c, d, e, and f is independently an integer of 0 to 200; the sum of a, b, c, d, e, and f is 1 or more; the order of the repeating units assigned with a, b, c, d, e, or f is arbitrary; and when all Rc's are hydrogen atoms or chlorine atoms, at least one of a, b, c, e, and f is 1 or more.)

[0034] Rc is preferably a hydrogen atom or a fluorine atom, more preferably a fluorine atom, That is, Rf in formula (5) is preferably a perfluoropolyether group.

[0035] Preferably, a, b, c, d, e and f are each independently an integer of 0 to 100.

[0036] The sum of a, b, c, d, e, and f is preferably 5 or more, more preferably 10 or more, and may be 15 or more or 20 or more. The sum of a, b, c, d, e, and f is preferably 100 or less, more preferably 60 or less, and may be 50 or less or 30 or less.

[0037] Each repeating unit to which a, b, c, d, e, or f is assigned may be linear or branched. ６ F １２ )- is, for example, -(OCF ２ CF ２ CF ２ CF ２ CF ２ CF ２ )-,-(OCF(CF ３ )CF ２ CF ２ CF ２ CF ２ ) -, -(OCF ２ CF (CF ３ )CF ２ CF ２ CF ２ ) -, -(OCF ２ CF ２ CF (CF３ )CF ２ CF ２ ) -, -(OCF ２ CF ２ CF ２ CF (CF ３ )CF ２ ) -, -(OCF ２ CF ２ CF ２ CF ２ CF (CF ３ ))-. ５ F １０ )- is, for example, -(OCF ２ CF ２ CF ２ CF ２ CF ２ )-,-(OCF(CF ３ )CF ２ CF ２ CF ２ ) -, -(OCF ２ CF (CF ３ )CF ２ CF ２ ) -, -(OCF ２ CF ２ CF (CF ３ )CF ２ ) -, -(OCF ２ CF ２ CF ２ CF (CF ３ ))-. ４ F ８ )- is, for example, -(OCF ２ CF ２ CF ２ CF ２ )-,-(OCF(CF ３ )CF ２ CF ２ ) -, -(OCF ２ CF (CF ３ )CF ２ ) -, -(OCF ２ CF ２ CF (CF ３ )) -, -(OC(CF ３ ) ２ CF ２ ) -, -(OCF ２ C (CF ３ )２ )-,-(OCF(CF ３ )CF(CF ３ ))-,-(OCF(C ２ F ５ )CF ２ ) -, -(OCF ２ CF (C ２ F ５ ))-. ３ F ６ )-(that is, in the above formula (Rf-I), when all Rc's are fluorine atoms), can be represented by, for example, -(OCF ２ CF ２ CF ２ )-,-(OCF(CF ３ )CF ２ ) -, -(OCF ２ CF (CF ３ ))-. ２ F ４ )- is, for example, -(OCF ２ CF ２ )-,-(OCF(CF ３ ))-.

[0038] Rf may be a group represented by any one of the following formulae (Rf-II) to (Rf-IV): Formula (Rf-II): -(OC ３ F ６ ) d-(OC ２ F ４ )e- (wherein d is an integer of 1 to 200, and e is 0 or 1) Formula (Rf-I-II): -(OC ４ F ８ ) c-(OC ３ F ６ ) d-(OC ２ F ４ ) e-(OCF ２ )f- (wherein c and d each independently represent an integer of 0 to 30, e and f each independently represent an integer of 1 to 200, the sum of c, d, e and f is 2 or more, and the order of the repeating units assigned with c, d, e or f is arbitrary.) Formula (Rf-I-III): -(R ２０ -R ２１ ) g- (wherein, R ２０ is OCF２ or O.C. ２ F ４ and R ２１ is O.C. ２ F ４ , O.C. ３ F ６ , O.C. ４ F ８ , O.C. ５ F １０ and O.C. ６ F １２ or a combination of two or three groups selected from these groups, and g is an integer of 2 to 100.) Formula (Rf-I-IV): -(OC ６ F １２ ) a-(OC ５ F １０ ) b-(OC ４ F ８ ) c-(OC ３ F ６ ) d-(OC ２ F ４ ) e-(OCF ２ )f- (wherein e is an integer of 1 to 200, a, b, c, d and f each independently are an integer of 0 to 200, and the order of the repeating units to which a, b, c, d, e or f is assigned is arbitrary.) Formula (Rf-IV): -(OC ６ F １２ ) a-(OC ５ F １０ ) b-(OC ４ F ８ ) c-(OC ３ F ６ ) d-(OC ２ F ４ ) e-(OCF ２ )f- (wherein f is an integer of 1 to 200, a, b, c, d, and e each independently are an integer of 0 to 200, and the order of the repeating units assigned a, b, c, d, e, or f is arbitrary.)

[0039] In the above formula (Rf-II), d is preferably 5 to 200, more preferably 10 to 100, and even more preferably 15 to 50, and may be 25 to 35. The above formula (Rf-II) is preferably -(OCF ２ CF２ CF ２ ) d- or -(OCF(CF ３ )CF ２ ) d- is a group represented by the formula:

[0040] In the above formula (Rf-I-II), e and f are each independently an integer of preferably 5 to 200, more preferably 10 to 200. The sum of c, d, e and f is preferably 5 or more, more preferably 10 or more, and may be 15 or more or 20 or more. The above formula (Rf-I-II) is preferably -(OCF ２ CF ２ CF ２ CF ２ )c-(OCF ２ CF ２ CF ２ ) d-(OCF ２ CF ２ ) e-(OCF ２ )f-, or a group represented by -(OC ２ F ４ ) e-(OCF ２ )f-, and more preferably, -(OC ２ F ４ ) e-(OCF ２ )f- is a group represented by the formula:

[0041] In the above formula (Rf-I-III), R ２０ is preferably OC ２ F ４ and R ２１ is preferably OC ２ F ４ , O.C. ３ F ６ and O.C. ４ F ８ or a combination of two or three groups independently selected from these groups, more preferably OC ３ F ６ and O.C. ４ F ８ is a group selected from ２ F ４ , O.C. ３ F ６ and O.C. ４ F ８Examples of the combination of two or three groups independently selected from the group consisting of, but not limited to, -OC ２ F ４ O.C. ３ F ６ -, -OC ２ F ４ O.C. ４ F ８ -, -OC ３ F ６ O.C. ２ F ４ -, -OC ３ F ６ O.C. ３ F ６ -, -OC ３ F ６ O.C. ４ F ８ -, -OC4F8OC ４ F ８ -, -OC ４ F ８ O.C. ３ F ６ -, -OC ４ F ８ O.C. ２ F ４ -, -OC ２ F ４ OC2F4OC ３ F ６ -, -OC ２ F ４ O.C. ２ F ４ O.C. ４ F ８ -, -OC ２ F ４ O.C. ３ F ６ OC2F4-, -OC ２ F ４ O.C. ３ F ６ O.C. ３ F ６ -, -OC ２ F ４ O.C. ４ F ８ O.C. ２ F ４ -, -OC ３ F ６ O.C. ２ F ４ O.C. ２ F ４-, -OC ３ F ６ O.C. ２ F ４ O.C. ３ F ６ -, -OC ３ F ６ OC3F6OC ２ F ４ - and -OC ４ F ８ O.C. ２ F ４ O.C. ２ F ４ In the above formula (Rf-I-III), g is preferably an integer of 3 or more, more preferably an integer of 5 or more. The above g is preferably an integer of 50 or less. In the above formula (Rf-I-III), OC ２ F ４ , O.C. ３ F ６ , O.C. ４ F ８ , O.C. ５ F １０ , and O.C. ６ F １２ may be either a straight chain or a branched chain, and is preferably a straight chain. In this embodiment, the above formula (Rf-I-III) is preferably —(OC ２ F ４ -OC ３ F ６ ) g- or -(OC ２ F ４ -OC ４ F ８ ) g-.

[0042] In the above formula (Rf-I-IV), e is preferably an integer of 1 to 100, more preferably an integer of 5 to 100. The sum of a, b, c, d, e, and f is preferably 5 or more, more preferably 10 or more, for example, 10 to 100.

[0043] In the above formula (Rf-IV), f is preferably an integer of 1 to 100, more preferably an integer of 5 to 100. The sum of a, b, c, d, e, and f is preferably 5 or more, more preferably 10 or more, for example, 10 to 100.

[0044] In Rf, the ratio of e to f (hereinafter referred to as the "e / f ratio") may be 0.5 to 4, preferably 0.6 to 3, more preferably 0.7 to 2, and even more preferably 0.8 to 1.4. By setting the e / f ratio to 4 or less, lubricity and chemical stability are further improved. The smaller the e / f ratio, the more improved the lubricity. On the other hand, by setting the e / f ratio to 0.5 or more, the stability of the compound can be further increased. The larger the e / f ratio, the more improved the stability of the fluoropolyether structure. In this case, the e / f ratio is preferably 0.8 or more.

[0045] Rf is represented by the following formula (Rf-I-VI): -(OCF ２ CF ２ CF ２ )a-(OCF(CF ３ )CF ２ ) b-(OCF ２ CF(CF3))c-(OCF ２ CF ２ )d-(OCF(CF ３ ))e-(OCF ２ )f- (wherein a, b, c, d, e, and f each independently represent an integer of 0 to 200, the sum of a, b, c, d, e, and f is 1 or more, and the order of the repeating units assigned with a, b, c, d, e, or f is arbitrary).

[0046] Rf is represented by the following formula (Rf-I-VII): -(OCF ２ CF ２ )d-(OCF(CF ３ ))e-(OCF ２ )f- (wherein d, e, and f each independently represent an integer of 0 to 200, the sum of d, e, and f is 1 or more, and the order of the repeating units to which d, e, or f is added is arbitrary.) When Rf is this group, it is thought that an increase in the number of ether bonds facilitates coordination of salt cations, thereby improving salt solubility.

[0047] In Rf, the ratio of d to f (hereinafter referred to as the "d / f ratio") may be 0.5 to 4, preferably 0.6 to 3, more preferably 0.7 to 2, and even more preferably 0.8 to 1.4. By setting the d / f ratio to 4 or less, lubricity and chemical stability are further improved. The smaller the d / f ratio, the more improved the lubricity. On the other hand, by setting the d / f ratio to 0.5 or more, the stability of the compound can be further increased. The larger the d / f ratio, the more improved the stability of the fluoropolyether structure. In this case, the d / f ratio is preferably 0.8 or more.

[0048] Each Rf is preferably independently a group represented by the above formula (Rf-II) or (Rf-I-II), and more preferably a group represented by the above formula (Rf-I-II).

[0049] The number average molecular weight of Rf is not particularly limited, but is, for example, 500 to 30,000, preferably 1,500 to 30,000, and more preferably 2,000 to 10,000. １９ This is a value measured by F-NMR.

[0050] R １ ~R ３ The alkyl group and fluoroalkyl group of R may be linear or branched, but are preferably linear. １ ~R ３ Examples of the aryl group include a phenyl group, a 4-nitrophenyl group, a 4-acetylaminophenyl group, and a 4-methanesulfonylphenyl group.

[0051] R １ ~R ３ are each independently preferably an alkyl group having 1 to 3 carbon atoms or a fluoroalkyl group having 1 to 3 carbon atoms, more preferably a methyl group, an ethyl group, a trifluoromethyl group or a pentafluoroethyl group, and even more preferably a methyl group, a trifluoromethyl group or a pentafluoroethyl group.

[0052] R ４The alkyl ester group may be linear or branched.

[0053] R ４ Examples of the substituent that the amide group or amino group may have include an alkyl group, an alkoxy group, and a hydroxy group.

[0054] R ４ are each independently preferably a fluorine atom, a hydrogen atom, a hydroxyl group, an aldehyde group, a carboxylic acid group, an alkyl ester group having 1 to 10 carbon atoms, an amide group which may have a substituent, or an amino group which may have a substituent, and more preferably a fluorine atom. ４ is a fluorine atom, R ４ -Rb ４ and Rb ４ -R ４ , that is, R ４ -Rf １ and Rf ２ -R ４ are each independently -CF ３ , -CF ２ CF ３ , and -CF ２ CF ２ CF ３ It may be a group selected from the group consisting of:

[0055] The fluoropolyether is particularly preferably the fluoropolyether represented by the formula (1) above, since it has good sheet strength and the like.

[0056] The fluoropolyether is preferably liquid at any temperature between 25°C and 80°C because it has good sheet strength and the like. Examples of a form "liquid at any temperature between 25°C and 80°C" include a form that is solid at 25°C and liquid at 50°C, or a form that is solid at 50°C and liquid at 80°C. A form that is liquid at low temperatures and solid at high temperatures does not normally exist, and therefore is not included in the form "liquid at any temperature between 25°C and 80°C".

[0057] In the mixture for electrochemical devices according to the present disclosure, the content of the fluoropolyether is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, even more preferably 1.0% by mass or more, and is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less.

[0058] The fibrillating resin is a resin that easily fibrillates when shear stress is applied, and examples thereof include liquid crystal polymer (LCP), cellulose, acrylic resin, ultra-high molecular weight polyethylene, polytetrafluoroethylene (PTFE), etc. These may be used alone or in combination of two or more. Among these, PTFE is preferred from the viewpoints of chemical stability, thermal stability, and processability.

[0059] The PTFE may be a homopolymer of tetrafluoroethylene (TFE), or may be a modified PTFE containing a polymerized unit based on TFE (TFE unit) and a polymerized unit based on a modified monomer (hereinafter also referred to as "modified monomer unit"). The modified PTFE may contain 99.0 mass% or more of TFE unit and 1.0 mass% or less of modified monomer unit. The modified PTFE may also be composed of only TFE unit and modified monomer unit. The modified PTFE is preferred as the PTFE because it improves binding force, sheet strength and flexibility.

[0060] In order to improve the binding force, sheet strength, and flexibility of the modified PTFE, the content of the modified monomer unit is preferably in the range of 0.00001 to 1.0 mass% relative to the total polymerized units. The lower limit of the content of the modified monomer unit is more preferably 0.0001 mass%, even more preferably 0.001 mass%, even more preferably 0.005 mass%, and particularly preferably 0.010 mass%. The upper limit of the content of the modified monomer unit is preferably 0.90 mass%, more preferably 0.80 mass%, more preferably 0.50 mass%, even more preferably 0.40 mass%, and even more preferably 0.30 mass%. In this specification, the modified monomer unit refers to a part of the molecular structure of PTFE that is derived from the modified monomer.

[0061] The content of each of the above-mentioned polymerized units can be calculated by appropriately combining NMR, FT-IR, elemental analysis, and X-ray fluorescence analysis depending on the type of monomer.

[0062] The above-mentioned modified monomer is not particularly limited as long as it can be copolymerized with TFE, and for example, can be listed perfluoroolefin such as hexafluoropropylene (HFP); hydrogen-containing fluoroolefin such as trifluoroethylene, vinylidene fluoride (VDF); perhaloolefin such as chlorotrifluoroethylene (CTFE); perfluorovinyl ether; perfluoroallyl ether; (perfluoroalkyl) ethylene, ethylene etc. In addition, the modified monomer used can be one kind or multiple kinds.

[0063] The perfluorovinyl ether is not particularly limited, and examples thereof include perfluorovinyl ethers represented by the following general formula (A): CF ２ =CF-ORff (A) (wherein Rff represents a perfluoroorganic group). In this specification, the term "perfluoroorganic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are substituted with fluorine atoms. The perfluoroorganic group may have an ether oxygen.

[0064] Examples of the perfluorovinyl ether include perfluoro(alkyl vinyl ether) [PAVE], in which Rff in the general formula (A) is a perfluoroalkyl group having 1 to 10 carbon atoms. The number of carbon atoms in the perfluoroalkyl group is preferably 1 to 5.

[0065] Examples of the perfluoroalkyl group in the PAVE include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, and a perfluorohexyl group.

[0066] The perfluorovinyl ether further includes those in which Rff is a perfluoro(alkoxyalkyl) group having 4 to 9 carbon atoms in the general formula (A), and those in which Rff is a perfluoro(alkoxyalkyl) group having 4 to 9 carbon atoms in the general formula (A)

[0067]

[0068] (wherein m represents 0 or an integer of 1 to 4), and Rff is a group represented by the following formula:

[0069]

[0070] (wherein n represents an integer of 1 to 4).

[0071] The (perfluoroalkyl)ethylene [PFAE] is not particularly limited, and examples thereof include (perfluorobutyl)ethylene [PFBE] and (perfluorohexyl)ethylene.

[0072] Examples of perfluoroallyl ethers include those represented by the general formula (B): CF ２ =CF-CF ２ -ORff １ (B) (wherein, Rff １ represents a perfluoroorganic group.

[0073] The above Rff １ is preferably a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoroalkoxyalkyl group having 1 to 10 carbon atoms. ２ =CF-CF ２ -O-CF ３ , C.F. ２ =CF-CF ２ -O-C ２ F ５ , C.F. ２ =CF-CF ２ -O-C ３ F ７ , and CF ２ =CF-CF ２ -O-C ４ F ９ At least one selected from the group consisting of CF ２ =CF-CF ２ -O-C ２ F ５ , C.F. ２ =CF-CF ２ -O-C ３ F ７ , and CF ２=CF-CF ２ -O-C ４ F ９ More preferably, at least one selected from the group consisting of CF ２ =CF-CF ２ -O-CF ２ CF ２ CF ３ is more preferred.

[0074] The modified monomer is preferably at least one selected from the group consisting of PAVE, HFP, VDF, and CTFE, and more preferably at least one selected from the group consisting of perfluoro(methyl vinyl ether) [PMVE], HFP, VDF, and CTFE, in terms of improving the stretchability, binding strength, and flexibility of the composite sheet.

[0075] The PTFE may have a core-shell structure. Examples of PTFE having a core-shell structure include modified PTFE particles containing a core of high molecular weight PTFE and a shell of lower molecular weight PTFE or modified PTFE. Examples of such modified PTFE include the PTFE described in JP-A-2005-527652.

[0076] Examples of commonly available PTFE include F-104, F-106, F-107, F-104C, F-121, F-201, F-205, F-208, and F-302 manufactured by Daikin Industries, Ltd.; 60X, 601X, 602X, 605XTX, 613AX, 62X, 62NX, 62XTX, 640XTX, 641XTX, 650XTX, 669X, 669NX, 6CX, 6CNX, CFP6000X, 6J, 6CJ, 62J, 640J, and 641J manufactured by Chemours; and T F2029, TF2025Z, TF2053Z, TF2073Z, TF2001Z, TF2071USZ, TF2072Z, etc.; CD145, CD123, CD126E, CD097, CD084E, CD086EL, CD086EH, CD090E, CD122E, CD141E, CD127E, etc. manufactured by AGC; and DF681F, DF680F, DF330F, DF291F, DF230F, DF210F, DF132F, DF130F, DF120F manufactured by Solvay.

[0077] The PTFE preferably has an endothermic peak temperature of 320°C or higher, more preferably 325°C or higher, even more preferably 330°C or higher, even more preferably 335°C or higher, even more preferably 340°C or higher, even more preferably 342°C or higher, and particularly preferably 344°C or higher, in order to form a composite sheet with even greater strength. The endothermic peak temperature is also preferably 350°C or lower. The endothermic peak temperature is the temperature corresponding to the minimum point in the heat of fusion curve obtained by performing differential scanning calorimetry (DSC) at a heating rate of 10°C / min on PTFE that has no history of being heated to a temperature of 300°C or higher. When there are two or more minimum points in one melting peak, each of them is taken as the endothermic peak temperature.

[0078] The PTFE preferably exhibits one or more endothermic peaks in the range of 333 to 347°C in the heat of fusion curve when heated at a rate of 10°C / min using a differential scanning calorimeter (DSC), and the heat of fusion at 290 to 350°C calculated from the heat of fusion curve is 62mJ / mg or more.

[0079] In the mixture for electrochemical devices according to the present disclosure, the content of the fibrillar resin is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.5% by mass or more, and is preferably 10% by mass or less, more preferably 5% by mass or less, and even more preferably 3% by mass or less.

[0080] The electrochemical device material may be, for example, an electrode active material. That is, the mixture for electrochemical devices according to the present disclosure may be an electrode mixture containing an electrode active material.

[0081] The electrode active material may be a positive electrode active material or a negative electrode active material.

[0082] The positive electrode active material is not particularly limited as long as it can electrochemically absorb and release alkali metal ions, but for example, a material containing an alkali metal and at least one transition metal is preferred. Specific examples include alkali metal-containing transition metal composite oxides and alkali metal-containing transition metal phosphate compounds. Of these, alkali metal-containing transition metal composite oxides that generate high voltage are particularly preferred as the positive electrode active material. Examples of the alkali metal ions include lithium ions, sodium ions, and potassium ions, with lithium ions being preferred.

[0083] Examples of the alkali metal-containing transition metal composite oxide include those represented by the formula: M ａ Mn ２－ｂ M １ ｂ O ４ (Wherein, M is at least one metal selected from the group consisting of Li, Na, and K; 0.9≦a; 0≦b≦1.5; M １ and Mn is at least one metal selected from the group consisting of Fe, Co, Ni, Cu, Zn, Al, Sn, Cr, V, Ti, Mg, Ca, Sr, B, Ga, In, Si, and Ge), a lithium-manganese spinel composite oxide represented by the formula: MNi １－ｃ M ２ ｃ O ２ (Wherein, M is at least one metal selected from the group consisting of Li, Na, and K; 0≦c≦0.5; M ２ is at least one metal selected from the group consisting of Fe, Co, Mn, Cu, Zn, Al, Sn, Cr, V, Ti, Mg, Ca, Sr, B, Ga, In, Si, and Ge), or a lithium-nickel composite oxide represented by the formula: MCo １－ｄ M ３ ｄ O ２ (Wherein, M is at least one metal selected from the group consisting of Li, Na, and K; 0≦d≦0.5; M ３and M is at least one metal selected from the group consisting of Fe, Ni, Mn, Cu, Zn, Al, Sn, Cr, V, Ti, Mg, Ca, Sr, B, Ga, In, Si, and Ge. In the above, M is preferably one metal selected from the group consisting of Li, Na, and K, more preferably Li or Na, and even more preferably Li.

[0084] Among these, MCoO is preferred because it can provide a secondary battery with high energy density and high output. ２ , M MnO ２ , MNiO ２ , M.M. ２ O ４ , MNi ０．８ Mn ０．１ Co ０．１ O ２ , MNi ０．８ Co ０．１５ Al ０．０５ O ２ , or MNi １／３ Co １／３ Mn １／３ O ２ etc. are preferred, and compounds represented by the following general formula are preferred. ０．８ Mn ０．１ Co ０．１ O ２ is particularly preferred. ｈ Co ｉ Mn ｊ M ５ ｋ O ２ (wherein M is at least one metal selected from the group consisting of Li, Na, and K, and M ５ represents at least one selected from the group consisting of Fe, Cu, Zn, Al, Sn, Cr, V, Ti, Mg, Ca, Sr, B, Ga, In, Si, and Ge, and (h+i+j+k)=1.0, 0≦h≦1.0, 0≦i≦1.0, 0≦j≦1.5, 0≦k≦0.2.

[0085] Examples of the alkali metal-containing transition metal phosphate compound include those represented by the following general formula: ｅ M ４ ｆ (P.O. ４ )ｇ (wherein M is at least one metal selected from the group consisting of Li, Na, and K, and M ４ represents at least one selected from the group consisting of V, Ti, Cr, Mn, Fe, Co, Ni, and Cu, and 0.5≦e≦3, 1≦f≦2, and 1≦g≦3. In the above, M is preferably one metal selected from the group consisting of Li, Na, and K, more preferably Li or Na, and even more preferably Li.

[0086] The transition metal in the alkali metal-containing transition metal phosphate compound is preferably V, Ti, Cr, Mn, Fe, Co, Ni, Cu, or the like, and specific examples thereof include LiFePO ４ , Li ３ Fe ２ (P.O. ４ ) ３ , LiFeP ２ O ７ Iron phosphates such as LiCoPO ４ and lithium transition metal phosphate compounds in which a part of the transition metal atoms constituting the main component of these compounds is substituted with other elements such as Al, Ti, V, Cr, Mn, Fe, Co, Li, Ni, Cu, Zn, Mg, Ga, Zr, Nb, Si, etc. The lithium-containing transition metal phosphate compounds are preferably those having an olivine structure, such as LiFePO ４ is particularly preferred.

[0087] Other examples of the positive electrode active material include lithium-nickel-based composite oxides. The lithium-nickel-based composite oxides are represented by the following general formula: Li ｙ Ni １－ｘ M ｘ O ２ (wherein x is 0.01≦x≦0.7, y is 0.9≦y≦2.0, and M is a metal atom (excluding Li and Ni)) is preferred.

[0088] Other positive electrode active materials include MFePO ４ , MNi ０．８ Co ０．２ O ２ , M １．２ Fe０．４ Mn ０．４ O ２ , MNi ０．５ Mn １．５ O ２ , M.V. ３ O ６ , M ２ MnO ３ In particular, M ２ MnO ３ , MNi ０．５ Mn １．５ O ２ These positive electrode active materials are preferred in that their crystalline structure does not collapse even when the secondary battery is operated at a voltage exceeding 4.4 V or a voltage of 4.6 V or higher. Therefore, electrochemical devices such as secondary batteries using positive electrode materials containing the above-mentioned positive electrode active materials are preferred because they are less likely to reduce their remaining capacity and change their resistance increase rate even when stored at high temperatures, and their battery performance does not deteriorate even when operated at high voltages.

[0089] Other positive electrode active materials include M ２ MnO ３ and M.M. ６ O ２ (wherein M is at least one metal selected from the group consisting of Li, Na, and K, and M ６ Examples of the material include solid solution materials with transition metals such as Co, Ni, Mn, and Fe.

[0090] The solid solution material may be, for example, a material represented by the general formula M ｘ [Mn （１－ｙ） M ７ ｙ ]O ｚ In the formula, M is at least one metal selected from the group consisting of Li, Na, and K, and M ７ is composed of at least one metal element other than M and Mn, and contains, for example, one or more elements selected from the group consisting of Co, Ni, Fe, Ti, Mo, W, Cr, Zr and Sn. The values ​​of x, y and z in the formula are in the ranges of 1<x<2, 0≦y<1 and 1.5<z<3. Among them, Li １．２ Mn ０．５ Co ０．１４ Ni ０．１４ O２ Li like ２ MnO ３ Based on LiNiO ２ and LiCoO ２ A manganese-containing solid solution material containing manganese is preferred in that it can provide an alkali metal ion secondary battery having a high energy density.

[0091] Furthermore, it is preferable to include lithium phosphate in the positive electrode active material, since this improves continuous charging characteristics. Although there is no limitation on the use of lithium phosphate, it is preferable to use a mixture of the positive electrode active material and lithium phosphate. The amount of lithium phosphate used, based on the total amount of the positive electrode active material and lithium phosphate, is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, and is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less.

[0092] Alternatively, a substance having a different composition may be attached to the surface of the positive electrode active material, such as an oxide, such as aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, calcium oxide, boron oxide, antimony oxide, or bismuth oxide; a sulfate, such as lithium sulfate, sodium sulfate, potassium sulfate, magnesium sulfate, calcium sulfate, or aluminum sulfate; a carbonate, such as lithium carbonate, calcium carbonate, or magnesium carbonate; or carbon.

[0093] The positive electrode active material may be used alone or in any combination or ratio of two or more different types of materials. ２ and LiNi ０．３３ Co ０．３３ Mn ０．３３ O ２ combination with ternary systems such as LiCoO ２ and LiMn ２ O ４ Or a combination of this with a material in which a part of Mn is replaced with another transition metal, or LiFePO ４ and LiCoO ２ Alternatively, a combination of Co with other transition metals or the like may be used.

[0094] The content of the positive electrode active material is preferably 50 to 90% by mass of the positive electrode mixture in terms of high battery capacity. The content in the positive electrode active material layer is preferably 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 75% by mass or more. The upper limit is preferably 88% by mass or less, more preferably 86% by mass or less. If the content of the positive electrode active material in the positive electrode active material layer is low, the electrical capacity may be insufficient. Conversely, if the content is too high, the ionic conductivity, electronic conductivity, and electrode strength may be insufficient.

[0095] The negative electrode active material is not particularly limited, and examples thereof include carbonaceous materials such as lithium metal, artificial graphite, graphite carbon fiber, resin-baked carbon, pyrolytic vapor-grown carbon, coke, mesocarbon microbeads (MCMB), furfuryl alcohol resin-baked carbon, polyacene, pitch-based carbon fiber, vapor-grown carbon fiber, natural graphite, and non-graphitizable carbon; silicon-containing compounds such as silicon and silicon alloys; Li ４ Ti ５ O １２ Among these, those containing at least a carbonaceous material and silicon-containing compounds are particularly suitable.

[0096] The negative electrode active material used in the present disclosure preferably contains silicon as a constituent element, which allows the production of a high-capacity battery.

[0097] The silicon-containing material includes silicon particles, particles having a structure in which silicon particles are dispersed in a silicon-based compound, and silicon-based particles having the general formula SiO ｘ (0.5≦x≦1.6), or a mixture thereof. By using these, a negative electrode mixture for a lithium ion secondary battery having higher initial charge / discharge efficiency, high capacity, and excellent cycle characteristics can be obtained.

[0098] Silicon oxide in the present disclosure is a general term for amorphous silicon oxide, and silicon oxide before disproportionation has the general formula SiO ｘ(0.5≦x≦1.6). Preferably, x satisfies 0.8≦x<1.6, and more preferably 0.8≦x<1.3. This silicon oxide can be obtained, for example, by heating a mixture of silicon dioxide and metallic silicon to produce silicon monoxide gas, which is then cooled and precipitated.

[0099] The content of the negative electrode active material is preferably 50 to 90% by mass of the negative electrode mixture in terms of high battery capacity. The content in the negative electrode active material layer is preferably 60% by mass or more, more preferably 70% by mass or more, and particularly preferably 75% by mass or more. The upper limit is preferably 88% by mass or less, more preferably 86% by mass or less. If the content of the negative electrode active material in the negative electrode active material layer is low, the electrical capacity may be insufficient. Conversely, if the content is too high, the ionic conductivity, electronic conductivity, and electrode strength may be insufficient.

[0100] The electrochemical device material may be a solid electrolyte. That is, the mixture for an electrochemical device according to the present disclosure may be a solid electrolyte mixture containing a solid electrolyte.

[0101] The solid electrolyte may be a sulfide-based solid electrolyte or an oxide-based solid electrolyte. In particular, when a sulfide-based solid electrolyte is used, it has the advantage of being flexible.

[0102] The sulfide-based solid electrolyte is not particularly limited, and may be Li ２ S-P ２ S ５ , Li ２ S-P ２ S ３ , Li ２ S-P ２ S ３ -P ２ S ５ , Li ２ S-SiS ２ , LiI-Li ２ S-SiS ２ , LiI-Li ２ S-P ２ S ５ , LiI-Li ２ S-P ２ O ５ , LiI-Li ３ P.O. ４ -P ２S ５ , LiI-Li ２ S-SiS ２ -P ２ S ５ , Li ２ S-SiS ２ -Li ４ SiO ４ , Li ２ S-SiS ２ -Li ３ P.O. ４ , Li ３ P.S. ４ -Li ４ GeS ４ , Li ３．４ P ０．６ Si ０．４ S ４ , Li ３．２５ P ０．２５ Ge ０．７６ S ４ , Li ４－ｘ Ge １－ｘ P ｘ S ４ (x=0.6~0.8), Li ４＋ｙ Ge １－ｙ Ga ｙ S ４ (y=0.2-0.3), LiPSCl, LiCl, Li ７－ｘ－２ｙ P.S. ６－ｘ－ｙ Cl ｘ (0.8≦x≦1.7, 0<y≦-0.25x+0.5), Li １０ SnP ２ S １２ Any one selected from the above, or a mixture of two or more thereof, can be used.

[0103] The sulfide-based solid electrolyte preferably contains lithium. Sulfide-based solid electrolytes containing lithium are used in solid-state batteries that use lithium ions as a carrier, and are particularly preferred in terms of electrochemical devices having high energy density.

[0104] In the mixture for electrochemical devices according to the present disclosure, the content of the solid electrolyte is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 40% by mass or more, and is preferably 99% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less.

[0105] The mixture for electrochemical devices according to the present disclosure may be an electrode mixture for a solid battery containing an electrode active material and a solid electrolyte.

[0106] In the electrochemical device mixture of the present disclosure, the content of the electrochemical device material is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, and is preferably 99.5% by mass or less, more preferably 98.5% by mass or less, and even more preferably 97.5% by mass or less.

[0107] In the mixture for electrochemical devices of the present disclosure, the content of the polyalkylene oxide represented by the following formula (6) is preferably less than 20% by mass. This ensures good ionic conductivity. If the content is 20% by mass or more, the viscosity of the composition increases, the ionic conductivity decreases, and at the same time, the electrochemical stability tends to decrease. (6) R １Ｂ -(OCHR １Ａ (CH ２ ) jCHR ２Ａ ) n-OR ２Ｂ (In the formula, R １Ａ and R ２Ａ are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, j is an integer of 0 or 1 or 2, and R １Ｂ and R ２Ｂ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and n is an integer of 5 to 1000.

[0108] In the mixture for electrochemical devices of the present disclosure, the content of the polyalkylene oxide represented by the above formula (6) is more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 1% by mass or less. The lower limit is not particularly limited, and may be 0% by mass.

[0109] The mixture for electrochemical devices of the present disclosure may contain a lithium salt. By containing a lithium salt, the conductivity of lithium ions is improved.

[0110] Any lithium salt can be used, and specific examples include the following: LiPF ６ , LiBF ４ , LiClO ４ , LiAlF ４ , LiSbF ６ , LiTaF ６ , LiWF ７ , LiAsF ６ , LiAlCl ４ , LiI, LiBr, LiCl, LiB １０ Cl １０ , Li ２ SiF ６ , Li ２ PFO ３ , LiPO ２ F ２ Inorganic lithium salts such as LiWOF ５ Lithium tungstates such as HCO ２ Li, C.H. ３ CO ２ Li, C.H. ２ FCO ２ Li, CHF ２ CO ２ Li, CF ３ CO ２ Li, CF ３ CH ２ CO ２ Li, CF ３ CF ２ CO ２ Li, CF ３ CF ２ CF ２ CO ２ Li, CF ３ CF ２ CF ２ CF ２ CO ２ Lithium carboxylate salts such as Li; FSO ３ Li, C.H. ３ SO ３ Li, C.H. ２ FSO ３ Li, CHF ２ SO３ Li, CF ３ SO ３ Li, CF ３ CF ２ SO ３ Li, CF ３ CF ２ CF ２ SO ３ Li, CF ３ CF ２ CF ２ CF ２ SO ３ Li, lithium methyl sulfate, lithium ethyl sulfate (C ２ H ５ OSO ３ Lithium salts having an S═O group, such as lithium bis(trifluoromethanesulfonimide) (LiTFSI), lithium bis(monofluorosulfonimide) (LiFSI), and LiN(FCO). ２ , LiN(FCO)(FSO ２ ), LiN(FSO ２ ) ２ , LiN(FSO ２ ) (CF ３ SO ２ ), LiN(CF ３ SO ２ ) ２ , LiN(C ２ F ５ SO ２ ) ２ , lithium bisperfluoroethanesulfonylimide, lithium cyclic 1,2-perfluoroethanedisulfonylimide, lithium cyclic 1,3-perfluoropropanedisulfonylimide, lithium cyclic 1,2-ethanedisulfonylimide, lithium cyclic 1,3-propanedisulfonylimide, lithium cyclic 1,4-perfluorobutanedisulfonylimide, LiN(CF ３ SO ２ ) (FSO ２ ), LiN(CF ３ SO ２ ) (C ３ F ７ SO ２ ), LiN(CF ３ SO ２ ) (C４ F ９ SO ２ ), LiN (POF ２ ) ２ Lithium imide salts such as LiC(FSO ２ ) ３ , LiC(CF ３ SO ２ ) ３ , LiC(C ２ F ５ SO ２ ) ３ Lithium methide salts such as: ａ (C ｎ F ２ｎ＋１ ) ６－ａ (wherein a is an integer of 0 to 5, and n is an integer of 1 to 6) ３ (C ２ F ５ ) ３ , LiPF ３ (CF ３ ) ３ , LiPF ３ (iso-C ３ F ７ ) ３ , LiPF ５ (iso-C ３ F ７ ), LiPF ４ (CF ３ ) ２ , LiPF ４ (C ２ F ５ ) ２ ), LiPF ４ (CF ３ SO ２ ) ２ , LiPF ４ (C ２ F ５ SO ２ ) ２ , LiBF ３ CF ３ , LiBF ３ C ２ F ５ , LiBF ３ C ３ F ７ , LiBF ２ (CF ３ ) ２, LiBF ２ (C ２ F ５ ) ２ , LiBF ２ (CF ３ SO ２ ) ２ , LiBF ２ (C ２ F ５ SO ２ ) ２ Fluorine-containing organic lithium salts such as LiSCN and LiB(CN) ４ , LiB(C ６ H ５ ) ４ , Li ２ (C ２ O ４ ), LiP(C ２ O ４ ) ３ , Li ２ B １２ F ｂ H １２－ｂ (b is an integer of 0 to 3), etc.

[0111] Among them, LiTFSI, LiFSI, LiPF ６ , LiBF ４ , LiSbF ６ , LiTaF ６ , LiPO ２ F ２ , FSO ３ Li, CF ３ SO ３ Li, LiN (FSO ２ ) ２ , LiN(FSO ２ ) (CF ３ SO ２ ), LiN(CF ３ SO ２ ) ２ , LiN(C ２ F ５ SO ２ ) ２ , lithium cyclic 1,2-perfluoroethane disulfonylimide, lithium cyclic 1,3-perfluoropropane disulfonylimide, LiC(FSO ２ ) ３ , LiC(CF ３ SO ２ ) ３, LiC(C ２ F ５ SO ２ ) ３ , LiBF ３ CF ３ , LiBF ３ C ２ F ５ , LiPF ３ (CF ３ ) ３ , LiPF ３ (C ２ F ５ ) ３ and the like are preferred, and LiTFSI, LiFSI, LiPF ６ is particularly preferred.

[0112] These lithium salts may be used alone or in combination of two or more. A preferred example of a combination of two or more is LiPF ６ and LiBF ４ In combination with LiPF ６ and LiPO ２ F ２ , C ２ H ５ OSO ３ Li or FSO ３ When used in combination with Li, it has the effect of improving high-temperature storage characteristics, load characteristics, and cycle characteristics.

[0113] Another example is the combined use of an inorganic lithium salt and an organic lithium salt, which has the effect of suppressing deterioration due to high-temperature storage. ３ SO ３ Li, LiN (FSO ２ ) ２ , LiN(FSO ２ ) (CF ３ SO ２ ), LiN(CF ３ SO ２ ) ２ , LiN(C ２ F ５ SO ２ ) ２ , lithium cyclic 1,2-perfluoroethane disulfonylimide, lithium cyclic 1,3-perfluoropropane disulfonylimide, LiC(FSO ２ ) ３, LiC(CF ３ SO ２ ) ３ , LiC(C ２ F ５ SO ２ ) ３ , LiBF ３ CF ３ , LiBF ３ C ２ F ５ , LiPF ３ (CF ３ ) ３ , LiPF ３ (C ２ F ５ ) ３ etc. are preferred.

[0114] In the mixture for electrochemical devices of the present disclosure, the content of the lithium salt is preferably 0.1% by mass or more, more preferably 1% by mass or more, and is preferably 30% by mass or less, more preferably 20% by mass or less.

[0115] The electrochemical device mixture of the present disclosure may contain a conductive aid. Examples of the conductive aid include, but are not limited to, metal materials such as copper, nickel, and gold; graphite such as natural graphite and artificial graphite; carbon black such as acetylene black, ketjen black, channel black, furnace black, lamp black, and thermal black; and carbon materials such as needle coke, carbon nanotubes, fullerenes, and amorphous carbon such as VGCF. These may be used alone or in any combination and ratio of two or more.

[0116] In the mixture for electrochemical devices according to the present disclosure, the content of the conductive auxiliary is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and even more preferably 1% by mass or more, and is preferably 30% by mass or less, more preferably 15% by mass or less, and even more preferably 5% by mass or less.

[0117] In the mixture for electrochemical devices of the present disclosure, the fibrillar resin acts as a binder, but may further contain other binders. The other binders are not particularly limited, and examples thereof include resin-based polymers such as polyethylene, polypropylene, polyethylene terephthalate, polymethyl methacrylate, aromatic polyamide, chitosan, alginic acid, polyacrylic acid, polyimide, cellulose, and nitrocellulose; rubber-like polymers such as SBR (styrene-butadiene rubber), isoprene rubber, butadiene rubber, fluororubber, NBR (acrylonitrile-butadiene rubber), and ethylene-propylene rubber; styrene-butadiene-styrene block copolymers or hydrogenated products thereof; EPDM (ethylene-propylene copolymer); Examples of suitable polymers include thermoplastic elastomeric polymers such as styrene-ethylene-butadiene terpolymers, styrene-isoprene-styrene block copolymers, and hydrogenated products thereof; soft resinous polymers such as syndiotactic-1,2-polybutadiene, polyvinyl acetate, ethylene-vinyl acetate copolymers, and propylene-α-olefin copolymers; fluorine-containing polymers such as polyvinylidene fluoride, vinylidene fluoride copolymers, and tetrafluoroethylene-ethylene copolymers; and polymer compositions having ionic conductivity for alkali metal ions (particularly lithium ions). These may be used alone or in any combination and ratio of two or more.

[0118] In the mixture for electrochemical devices of the present disclosure, the content of the other binder is usually 0.01 to 3 mass %.

[0119] <Material Mixture Sheet for Electrochemical Device> The material mix for electrochemical devices of the present disclosure is preferably in the form of a sheet. The present disclosure also relates to a material mix sheet for electrochemical devices including the material mix for electrochemical devices of the present disclosure.

[0120] The thickness of the composite sheet for electrochemical devices according to the present disclosure is preferably 300 μm or less, more preferably 250 μm or less, even more preferably 200 μm or less, even more preferably 180 μm or less, and particularly preferably 150 μm or less, and is preferably 10 μm or more, more preferably 15 μm or more, and even more preferably 20 μm or more.

[0121] The mixture sheet for electrochemical devices according to the present disclosure can be used as a solid electrolyte mixture sheet or an electrode mixture sheet.

[0122] <Method for manufacturing a mixture sheet for electrochemical devices> The mixture sheet for electrochemical devices of the present disclosure can be obtained, for example, by a manufacturing method including a step (1) of mixing a fluoropolyether, a fibrillar resin, and a material for electrochemical devices, and a step (2) of rolling the mixture for electrochemical devices obtained in the step (1) into a sheet. The present disclosure also relates to the manufacturing method.

[0123] The fluoropolyether, fibrillar resin, and material for electrochemical devices in the above step (1) are the same as those described for the mixture for electrochemical devices of the present disclosure.

[0124] In the above step (1), the mixing conditions are preferably 3000 rpm or less. The speed is preferably 10 rpm or more, more preferably 15 rpm or more, and even more preferably 20 rpm or more, and is preferably 2000 rpm or less, more preferably 1500 rpm or less, and even more preferably 1000 rpm or less. If the speed is below the above range, mixing takes a long time, which affects productivity. If the speed is above the above range, fibrillation may proceed excessively, resulting in a mixture sheet with poor strength and flexibility.

[0125] In the above step (1), the materials may be mixed and then shaped into a bulk form. Specific methods for shaping into a bulk form include extrusion molding, press molding, etc. The term "bulk form" does not particularly specify a shape, and may refer to a state in which the material is in the form of a single mass, including rods, sheets, spheres, cubes, etc.

[0126] Specific examples of the rolling method in the step (2) include rolling using a roll press, a plate press, a calender roll, or the like.

[0127] Furthermore, after the above step (2), a step (3) may be carried out in which a larger load is applied to the obtained rolled sheet to roll it into an even thinner sheet, or step (3) may be carried out repeatedly. In this way, by rolling the rolled sheet little by little in stages rather than thinning it all at once, flexibility is improved. The number of times step (3) is carried out is preferably from 2 to 10 times, and more preferably from 3 to 9 times. Specific rolling methods include, for example, a method in which two or more rolls are rotated and the rolled sheet is passed between them to process it into a thinner sheet.

[0128] It is also preferable to include a step (4) after the step (2) or the step (3) in which the rolled sheet is crushed, re-formed into a bulk form, and rolled into a sheet. It is also preferable to repeat the step (4). The number of times of the step (4) is preferably from 1 to 12 times, more preferably from 2 to 11 times.

[0129] In the above step (4), specific methods for roughly crushing the rolled sheet and forming it into a bulk shape include folding the sheet, forming it into a rod or thin film sheet, chipping, etc. In the present disclosure, "rough crushing" means changing the shape of the rolled sheet obtained in step (2) or (3) into a different shape so that it can be rolled into a sheet in the next step, and also includes cases where the rolled sheet is simply folded.

[0130] Furthermore, step (4) may be followed by step (3) or may be repeated. Furthermore, uniaxial or biaxial stretching may be performed in steps (2), (3), and (4).

[0131] In the above steps (2), (3), and (4), the rolling ratio is preferably 10% or more, more preferably 20% or more, and preferably 80% or less, more preferably 65% ​​or less, and even more preferably 50% or less. If the rolling ratio is below the above range, the number of rolling operations increases, which takes time and affects productivity. If the rolling ratio is above the above range, fibrillation may proceed excessively, resulting in a mixture sheet with poor strength and flexibility. The rolling ratio here refers to the reduction rate of the thickness of the sample after processing relative to the thickness before rolling. The sample before rolling may be a bulk raw material composition or a sheet-like raw material composition. The thickness of the sample refers to the thickness in the direction in which a load is applied during rolling.

[0132] <Electrochemical Device> The present disclosure also relates to an electrochemical device using the mixture sheet for an electrochemical device of the present disclosure.

[0133] The electrochemical device of the present disclosure may use the mixture sheet for electrochemical device of the present disclosure as an electrode mixture sheet, may use the mixture sheet for electrochemical device of the present disclosure as a solid electrolyte mixture sheet, or may use the mixture sheet as both an electrode mixture sheet and a solid electrolyte mixture sheet.

[0134] The electrochemical device of the present disclosure preferably comprises a positive electrode, a negative electrode, etc., and more specifically, is preferably a secondary battery comprising these, and particularly preferably a lithium ion secondary battery.

[0135] The positive electrode is preferably composed of a current collector and an electrode mixture sheet containing the positive electrode active material. Examples of materials for the positive electrode current collector include metals such as aluminum, titanium, tantalum, stainless steel, and nickel, or alloys thereof; and carbon materials such as carbon cloth and carbon paper. Among these, metal materials, particularly aluminum or its alloys, are preferred.

[0136] Examples of the shape of the current collector include metal foil, metal cylinder, metal coil, metal plate, expanded metal, punched metal, and foam metal in the case of a metal material, and carbon plate, carbon thin film, and carbon cylinder in the case of a carbon material. Of these, metal foil is preferred. The metal foil may be appropriately formed into a mesh shape. The thickness of the metal foil is optional, but is usually 1 μm or more, preferably 3 μm or more, and more preferably 5 μm or more, and is usually 1 mm or less, preferably 100 μm or less, and more preferably 50 μm or less. If the metal foil is thinner than this range, the strength required as a current collector may be insufficient. Conversely, if the metal foil is thicker than this range, handling may be impaired.

[0137] In addition, it is also preferable that the surface of the current collector is coated with a conductive additive, from the viewpoint of reducing the electrical contact resistance between the current collector and the positive electrode active material layer. Examples of the conductive additive include carbon and precious metals such as gold, platinum, and silver.

[0138] The positive electrode may be manufactured by a conventional method, for example, by laminating an electrode mixture sheet and a current collector with an adhesive therebetween, followed by vacuum drying.

[0139] The density of the positive electrode mixture sheet is preferably 2.80 g / cm ３ More preferably, 3.00 g / cm ３ More preferably, 3.20 g / cm ３ or more, and preferably 3.80 g / cm ３ or less, more preferably 3.75 g / cm ３ More preferably, 3.70 g / cm or less ３ The range is as follows. If the temperature exceeds this range, the permeability of the electrolyte to the vicinity of the current collector / active material interface will decrease, and the charge / discharge characteristics, especially at high current densities, will decrease, and high output may not be obtained. If the temperature falls below this range, the conductivity between the active materials will decrease, and the battery resistance will increase, and high output may not be obtained.

[0140] The negative electrode is preferably composed of a current collector and an electrode mixture sheet containing the negative electrode active material. Examples of materials for the negative electrode current collector include metals such as copper, nickel, titanium, tantalum, and stainless steel, or alloys thereof; and carbon materials such as carbon cloth and carbon paper. Among these, metal materials, particularly copper, nickel, and alloys thereof, are preferred.

[0141] Examples of the shape of the current collector include metal foil, metal cylinder, metal coil, metal plate, expanded metal, punched metal, and foam metal in the case of a metal material, and carbon plate, carbon thin film, and carbon cylinder in the case of a carbon material. Of these, metal foil is preferred. The metal foil may be appropriately formed into a mesh shape. The thickness of the metal foil is optional, but is usually 1 μm or more, preferably 3 μm or more, and more preferably 5 μm or more, and is usually 1 mm or less, preferably 100 μm or less, and more preferably 50 μm or less. If the metal foil is thinner than this range, the strength required as a current collector may be insufficient. Conversely, if the metal foil is thicker than this range, handling may be impaired.

[0142] The negative electrode may be produced by a conventional method, for example, by laminating the electrode mixture sheet and a current collector with an adhesive therebetween, followed by vacuum drying.

[0143] The density of the negative electrode mixture is preferably 1.3 g / cm ３ More preferably, 1.4 g / cm ３ More preferably, 1.5 g / cm ３ or more, and preferably 2.0 g / cm ３ or less, more preferably 1.9 g / cm ３ More preferably, 1.8 g / cm or less ３ The range is as follows. If the temperature exceeds this range, the permeability of the electrolyte to the vicinity of the current collector / active material interface will decrease, and the charge / discharge characteristics, especially at high current densities, will decrease, and high output may not be obtained. If the temperature falls below this range, the conductivity between the active materials will decrease, and the battery resistance will increase, and high output may not be obtained.

[0144] The secondary battery may be a secondary battery using an electrolytic solution or a solid-state secondary battery. In this specification, the solid-state secondary battery may be a secondary battery containing a solid electrolyte, and may be a semi-solid-state secondary battery containing a solid electrolyte and a liquid component as the electrolyte, or an all-solid-state secondary battery containing only a solid electrolyte as the electrolyte.

[0145] The secondary battery using the above-mentioned electrolyte solution can use the electrolyte solution, separator, etc. used in known secondary batteries, which will be described in detail below.

[0146] The electrolyte is preferably a non-aqueous electrolyte, which may be prepared by dissolving a known electrolyte salt in a known organic solvent for dissolving electrolyte salts.

[0147] The organic solvent for dissolving the electrolyte salt is not particularly limited, and one or more of known hydrocarbon solvents such as propylene carbonate, ethylene carbonate, butylene carbonate, γ-butyrolactone, 1,2-dimethoxyethane, 1,2-diethoxyethane, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate; and fluorine-based solvents such as fluoroethylene carbonate, fluoroethers, and fluorinated carbonates can be used.

[0148] As the electrolyte salt, the above-mentioned lithium salt can be used.

[0149] The concentration of the electrolyte salt is preferably 0.8 mol / L or more, more preferably 1.0 mol / L or more, and the upper limit is usually 1.5 mol / L or less, although it depends on the organic solvent used to dissolve the electrolyte salt.

[0150] A secondary battery using the above-mentioned electrolyte solution preferably further includes a separator. The material and shape of the separator are not particularly limited as long as it is stable to the electrolyte solution and has excellent liquid retention properties, and any known separator can be used. Among them, it is preferable to use a material that is stable to the electrolyte solution, such as resin, glass fiber, or inorganic material, and that is in the form of a porous sheet or nonwoven fabric with excellent liquid retention properties.

[0151] Examples of materials that can be used for the resin or glass fiber separator include polyolefins such as polyethylene and polypropylene, aromatic polyamides, polytetrafluoroethylene, polyethersulfone, and glass filters. These materials may be used alone or in any combination and ratio, such as polypropylene / polyethylene two-layer films and polypropylene / polyethylene / polypropylene three-layer films. Among these, porous sheets or nonwoven fabrics made from polyolefins such as polyethylene and polypropylene are preferred for the separator, due to their excellent electrolyte permeability and shutdown effect.

[0152] The thickness of the separator is not particularly limited, but is usually 1 μm or more, preferably 5 μm or more, more preferably 8 μm or more, and usually 50 μm or less, preferably 40 μm or less, more preferably 30 μm or less. If the separator is thinner than the above range, the insulating properties and mechanical strength may be reduced. If the separator is thicker than the above range, not only may the battery performance such as rate characteristics be reduced, but also the energy density of the entire electrolyte battery may be reduced.

[0153] On the other hand, inorganic materials include, for example, oxides such as alumina and silicon dioxide, nitrides such as aluminum nitride and silicon nitride, and sulfates such as barium sulfate and calcium sulfate, and these are used in particulate or fibrous form.

[0154] As for the form, a thin film such as a nonwoven fabric, a woven fabric, or a microporous film is used. A thin film with a pore size of 0.01 to 1 μm and a thickness of 5 to 50 μm is preferably used. In addition to the above-mentioned independent thin film, a separator can be used in which a composite porous layer containing the above-mentioned inorganic particles is formed on the surface layer of the positive electrode and / or negative electrode using a resin binder. For example, a porous layer can be formed on both sides of the positive electrode using alumina particles with a 90% particle size of less than 1 μm and a fibrillar resin as a binder.

[0155] The material of the outer case is not particularly limited as long as it is a substance that is stable against the electrolyte used. Specifically, metals such as nickel-plated steel sheet, stainless steel, aluminum or aluminum alloy, magnesium alloy, or a laminate film of resin and aluminum foil (laminate film) can be used. From the viewpoint of weight reduction, metals such as aluminum or aluminum alloy and laminate film are preferably used.

[0156] Examples of exterior cases using metals include those in which metals are welded together to form a sealed, airtight structure by laser welding, resistance welding, or ultrasonic welding, or those in which the metals are used via a resin gasket to form a crimped structure. Examples of exterior cases using the above-mentioned laminate film include those in which resin layers are heat-sealed to form a sealed, airtight structure. In order to improve sealing properties, a resin different from the resin used in the laminate film may be interposed between the resin layers. In particular, when a sealed structure is formed by heat-sealing the resin layers via a current collecting terminal, a resin having a polar group or a modified resin into which a polar group has been introduced is preferably used as the interposed resin, since the metal and the resin are bonded together.

[0157] The shape of the secondary battery using the above-mentioned electrolyte solution is arbitrary, and examples thereof include cylindrical, prismatic, laminated, coin, large, etc. The shapes and configurations of the positive electrode, negative electrode, and separator can be changed according to the shape of each battery.

[0158] The solid-state secondary battery is preferably an all-solid-state secondary battery, and is preferably a lithium-ion battery, and is also preferably a sulfide-based all-solid-state secondary battery.

[0159] The solid secondary battery preferably includes a positive electrode, a negative electrode, and a solid electrolyte layer interposed between the positive electrode and the negative electrode.

[0160] The solid secondary battery may include a separator between the positive electrode and the negative electrode. Examples of the separator include a porous membrane such as polyethylene or polypropylene; a nonwoven fabric made of a resin such as polypropylene; and a nonwoven fabric such as a glass fiber nonwoven fabric.

[0161] The solid secondary battery may further include a battery case. The shape of the battery case is not particularly limited as long as it can accommodate the above-mentioned positive electrode, negative electrode, solid electrolyte layer, etc., but specific examples include a cylindrical shape, a square shape, a coin shape, and a laminate shape.

[0162] The solid secondary battery can be produced, for example, by stacking a positive electrode, a solid electrolyte layer sheet, and a negative electrode in this order and pressing them together.

[0163] Although the embodiments have been described above, it will be understood that various changes in form and details can be made without departing from the spirit and scope of the claims.

[0164] Next, the present disclosure will be described with reference to examples, but the present disclosure is not limited to these examples.

[0165] The following compounds were used. Compounds 1-1 to 1-7 were liquid at 25°C. <Compound 1-1> CH ３ O (CH ２ CH ２ O) ｘ１ CH ２ CF ２ (OCF ２ CF ２ ) ｙ (OCF ２ ) ｚ OCF ２ CH ２ O (CH ２ CH ２ O) ｘ２ CH ３ (x1:4, y: average 12.3, z: average 10.2, x2:4, (CH ２ CH ２ Number average molecular weight of (CH ２ CH ２ O) ｘ２ Number average molecular weight: 176) <Compound 1-2> Compound having the same structure as Compound 1-1 (x1: average 8.4, y: average 12.3, z: average 10.2, x2: average 8.4, (CH ２ CH ２ O) ｘ１ Number average molecular weight: 400, (CH ２ CH ２ O)ｘ２ Number average molecular weight: 400) <Compound 1-3> CF ２ (CF ３ )CF ２ (OCF(CF ３ )CF ２ ) ｘ OCF (CF ３ )CH ２ O(CH ２ CH ２ O) ｙ CH ３ (x: average 9.4, y: 4, (CH ２ CH ２ O) ｙ Number average molecular weight: 176) <Compound 1-4> Compound 1-3 is an isostructural compound (x: average 14.3, y: 4, (CH ２ CH ２ O) ｙ Number average molecular weight: 176) <Compound 1-5> Fructus E10H (manufactured by ソルベイ Co., Ltd.) HO(CH ２ CH ２ O) ｘ１ CH ２ CF ２ O (CF ２ CF ２ O) ｘ２ (CF ２ O) ｙ CF ２ CH ２ O(CH ２ CH ２ O) ｘ３ H (x1: average 1.27, y: average 8.16, x2: average 7.09, x3: average 1.27) <Compound 1-6> CF ３ CF ２ (OCF ２ CF ２ ) ｘ１ (OCF ２ ) ｙ１ OCF ２ CH ２ O(CH ２ CH ２ O) ｚ CH ２ CF ２ (OCF ２ CF ２ ) ｘ２ (OCF ２ ) ｙ２OCF ２ CF ３ (x1: average 15.5, y1: average 13.0, z: average 4.1, x2: average 15.5, y2: average 13.0, (CH ２ CH ２ O) ｚ Number average molecular weight: 200) <Compound 1-7> A compound having a chemical structure represented by the following formula (I) (m: average 29.5, n: average 24.6, terminal R is CF ３ and CF ２ CF ３ are present in an average ratio of 1:0.17)

[0166]

[0167] <Compound 2-1> Ethyl methyl carbonate (EMC, manufactured by Kishida Chemical Co., Ltd.) <Compound 2-2> Polyethylene glycol 200 (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0168] Synthesis Example 1 Synthesis of Compound 1-1 600 mg of sodium hydroxide (FUJIFILM Wako Pure Chemical Industries, Ltd., 15.3 mmol), 30 g of 1,3-bis(trifluoromethyl)benzene (Tokyo Chemical Industry Co., Ltd.), and 10 g of fluoropolyether alcohol terminated at both ends (Solvay, Fomblin D2, 5.1 mmol) were added to a nitrogen-substituted reaction vessel, followed by heating and stirring at 70°C for 3 hours. The internal temperature was raised to 65°C, and 5.5 g of triethylene glycol-2-bromoethyl methyl ether (Tokyo Chemical Industry Co., Ltd., 20.4 mmol) was added dropwise from a dropping funnel over 10 minutes, followed by heating and stirring for 6 hours. After returning to room temperature, 5 ml of 1N hydrochloric acid was added to the reaction solution and stirred for 3 hours. This solution was washed four times with pure water, and 2 g of magnesium sulfate was added to the separated organic layer and dried. The magnesium sulfate was removed by filtration, and the volatiles were removed from the treated solution by distillation. Compound 1-1 was obtained by further drying at 100°C for 3 hours.

[0169] Synthesis Example 2 Synthesis of Tosylated Polyethylene Glycol Monomethyl Ether 8.0 g of polyethylene glycol monomethyl ether 400 (Tokyo Chemical Industry Co., Ltd., average molecular weight 380-420, 20.0 mmol), 25 mL of tetrahydrofuran (Tokyo Chemical Industry Co., Ltd.), and 4.7 g of p-toluenesulfonyl chloride (Tokyo Chemical Industry Co., Ltd., 25 mmol) were added to a nitrogen-purged reaction vessel and stirred until homogeneous. A solution of 3.4 g of potassium hydroxide (Fujifilm Wako Pure Chemical Industries, Ltd., 60 mmol) in 10 mL of pure water was added to the reaction vessel in an ice-water bath. After stirring for 10 minutes, the ice-water bath was removed and the mixture was stirred at room temperature for 12 hours. The reaction solution was poured into a mixture of 30 mL of ice-water and 60 mL of methylene chloride, and the aqueous layer was extracted three times with methylene chloride. 8 g of magnesium sulfate was added to the separated organic layer and the mixture was dried. The magnesium sulfate was removed by filtration, and the volatiles were removed from the treated solution by distillation to obtain a tosylated polyethylene glycol monomethyl ether.

[0170] (Synthesis Example 3) Synthesis of Compound 1-2 Compound 1-2 was obtained by reacting the tosylated polyethylene glycol monomethyl ether synthesized in Synthesis Example 2 under the reaction conditions of Synthesis Example 1, instead of triethylene glycol-2-bromoethyl methyl ether.

[0171] Synthesis Example 4 Synthesis of Compound 1-3 600 mg of sodium hydroxide (FUJIFILM Wako Pure Chemical Industries, Ltd., 15.3 mmol), 30 g of 1,3-bis(trifluoromethyl)benzene (Tokyo Chemical Industry Co., Ltd.), and 10.2 g of fluoropolyether monoterminated alcohol (Unichem Co., Ltd., perfluoropolyether modified, molecular weight 2000, 5.1 mmol) were added to a nitrogen-purged reaction vessel, and the mixture was heated and stirred at 70°C for 3 hours. The internal temperature was raised to 65°C, and 2.8 g of triethylene glycol-2-bromoethyl methyl ether (Tokyo Chemical Industry Co., Ltd., 10.0 mmol) was added dropwise from the dropping funnel over 10 minutes, followed by heating and stirring for 6 hours. After returning to room temperature, 5 ml of 1N hydrochloric acid was added to the reaction solution and the mixture was stirred for 3 hours. This solution was washed four times with pure water, and 2 g of magnesium sulfate was added to the separated organic layer and dried. The magnesium sulfate was removed by filtration, and the volatile matter was distilled off from the treated solution, which was then dried at 100° C. for 3 hours to obtain compound 1-3.

[0172] Synthesis Example 5 Synthesis of Compound 1-4 Compound 1-4 was obtained by the same reaction as in Synthesis Example 4, except that the fluoropolyether monoterminated alcohol was replaced with a perfluoropolyether modified product, molecular weight 3000, manufactured by Unichem Co., Ltd.

[0173] Synthesis Example 6 Synthesis of Compound 1-6 A nitrogen-purged reaction vessel was charged with 600 mg of sodium hydroxide (FUJIFILM Wako Pure Chemical Industries, Ltd., 15.3 mmol), 30 g of 1,3-bis(trifluoromethyl)benzene (Tokyo Chemical Industry Co., Ltd.), and 20.4 g of a fluoropolyether monoterminated alcohol (Fluorolink ZMF-402, Solvay, 5.1 mmol), followed by heating and stirring at 70°C for 3 hours. The internal temperature was raised to 65°C, and 1.3 g (2.5 mmol) of the polyethylene glycol with both terminal tosylation derivatives obtained in Synthesis Example 9 was dissolved in 5 g of 1,3-bis(trifluoromethyl)benzene and added dropwise from the dropping funnel over 10 minutes. The mixture was then heated and stirred for 6 hours. After returning to room temperature, 5 ml of 1N hydrochloric acid was added to the reaction solution, followed by stirring for 3 hours. This solution was washed four times with pure water, and 2 g of magnesium sulfate was added to the separated organic layer, followed by drying. The magnesium sulfate was removed by filtration, and the volatile matter was distilled off from the treated solution, followed by drying at 100° C. for 3 hours to obtain compound 1-6.

[0174] PTFE-1 to PTFE-3 were prepared and analyzed by the following method.

[0175] <Average primary particle diameter> The PTFE aqueous dispersion was diluted with water until the solid content became 0.15% by mass, and the transmittance of the 550 nm projected light per unit length of the diluted latex obtained and the number-based average primary particle diameter determined by measuring the unidirectional diameter by a transmission electron microscope photograph were measured, and a calibration curve was prepared. Using this calibration curve, the average primary particle diameter was determined from the measured transmittance of the 550 nm projected light of each sample.

[0176] <Polymer Solids Concentration> 1 g of the aqueous PTFE dispersion is dried in a blower dryer at 150°C for 60 minutes, and the ratio of the mass of the heating residue to the mass (1 g) of the aqueous dispersion is expressed as a percentage.

[0177] <Content of modified monomer> The CTFE content was determined by press-molding PTFE powder into a thin film disk, measuring the infrared absorbance of the thin film disk by FT-IR, and determining the CTFE content at 957 cm －１ Absorbance at / 2360 cm －１ The HFP content was calculated by multiplying the ratio of the absorbance at 982 cm by 0.58. A thin film disk was produced by press-molding the PTFE composition, and the thin film disk was measured for infrared absorbance by FT-IR. －１ Absorbance at / 935 cm －１ The absorbance ratio was calculated by multiplying the absorbance ratio at 0.3.

[0178] <Standard Specific Gravity (SSG)> Using a sample molded in accordance with ASTM D4895 89, the standard specific gravity was measured by the water displacement method in accordance with ASTM D 792.

[0179] A white solid A was obtained by the method described in Synthesis Example 1 of WO 2021 / 045228.

[0180] (Preparation Example 1) 3,480 g of deionized water, 100 g of paraffin wax, and 5.3 g of white solid A were charged into a 6-liter stainless steel autoclave equipped with a stirring blade and a temperature-controlling jacket, and the autoclave was heated to 70 ° C. while purging with nitrogen gas to remove oxygen. TFE was injected to adjust the system pressure to 0.78 MPaG, and the system temperature was maintained at 70 ° C. while stirring. Next, an aqueous solution prepared by dissolving 15.0 mg of ammonium persulfate in 20 g of water was injected with TFE to initiate the polymerization reaction. As the polymerization reaction progressed, the system pressure decreased, but TFE was added to maintain the system temperature at 70 ° C. and the system pressure at 0.78 MPaG. When 400 g of TFE had been consumed from the start of polymerization, an aqueous solution prepared by dissolving 18.0 mg of hydroquinone as a radical scavenger in 20 g of water was injected with TFE. Polymerization continues thereafter, and when the polymerization amount of TFE reaches about 1200 g from the start of polymerization, stirring and supply of TFE are stopped, and the gas in the system is immediately released to normal pressure, and polymerization reaction is terminated.The aqueous dispersion is taken out, cooled, and then the paraffin wax is separated, and a PTFE aqueous dispersion is obtained.The average primary particle diameter of the obtained PTFE aqueous dispersion is 310 nm, and the solid content concentration is 25.3 mass%.

[0181] The resulting PTFE aqueous dispersion was diluted to a solids concentration of 13% by mass, and the PTFE was coagulated while stirring in a container. The PTFE was then filtered off to obtain a wet PTFE powder. The resulting wet PTFE powder was dried at 180°C for 18 hours to obtain PTFE-1. The SSG of the resulting PTFE-1 was 2.156.

[0182] (Preparation Example 2) 3580 g of deionized water, 100 g of paraffin wax, and 5.4 g of white solid A were charged into a 6-liter stainless steel autoclave equipped with a stirring blade and a temperature-controlling jacket, and the autoclave was heated to 80 ° C. while replacing the atmosphere with nitrogen gas to remove oxygen. After adding 1.20 g of CTFE, TFE was further injected to bring the system pressure to 0.78 MPaG, and the system temperature was maintained at 80 ° C. while stirring. Next, an aqueous solution of 360 mg of disuccinic acid peroxide dissolved in 20 g of water and an aqueous solution of 10 mg of ammonium persulfate dissolved in 20 g of water were injected with TFE to initiate the polymerization reaction. As the polymerization reaction progressed, the system pressure decreased, but TFE was added to maintain the system temperature at 80 ° C. and the system pressure at 0.78 MPaG. When 1530g of TFE was consumed from the start of polymerization (conversion rate 90%), 4.2g of CTFE was added by pressure with TFE. Polymerization continued thereafter, and when the amount of TFE polymerization reached about 1700g from the start of polymerization, stirring and the supply of TFE were stopped, and the gas in the system was immediately released to normal pressure, and the polymerization reaction was terminated. The aqueous dispersion was taken out and cooled, and the paraffin wax was separated to obtain a PTFE aqueous dispersion. The average primary particle size of the obtained PTFE aqueous dispersion was 241nm, and the solid content concentration was 32.0% by mass.

[0183] The resulting PTFE aqueous dispersion was diluted to a solids concentration of 13% by mass, vigorously stirred in a container equipped with a stirrer to coagulate, and then filtered to separate the water, yielding a PTFE wet powder. The resulting PTFE wet powder was dried at 145°C for 18 hours to yield PTFE-2. The resulting PTFE-2 had a CTFE content of 0.23% by mass and an SSG of 2.170.

[0184] Preparation Example 1: 0.273 g of lauric acid was added to 16 g of deionized water, and 2.77 g of a 2.8% aqueous solution of ammonia was gradually added while stirring to obtain aqueous solution C. 10 g of lauric acid was added to 100 g of deionized water, and 25 g of a 10% aqueous solution of ammonia was gradually added while stirring to obtain aqueous solution D. The pH at this time was 9.6.

[0185] (Preparation Example 3) 1748 g of deionized water, 90 g of paraffin wax, the aqueous solution C obtained in Preparation Example 1, and 0.5 g of ammonium oxalate were added to a 3-liter stainless steel autoclave equipped with a stirring blade and a temperature-controlling jacket. The pH of the aqueous dispersion at this time was 9.0. The autoclave was sealed, and while heating to 70°C, the system was purged with nitrogen to remove oxygen. While stirring, the temperature in the system was maintained at 70°C, 2.0 g of HFP was added, and the pressure was further increased with TFE to 2.70 MPaG. When a 0.5% by mass aqueous potassium permanganate solution was continuously charged into the autoclave as a polymerization initiator, a drop in pressure occurred, and the reaction began. TFE was charged so that the system pressure was constant at 2.70 MPaG. When 80 g of TFE had been charged, stirring was stopped, and the system was depressurized until the pressure reached atmospheric pressure. Immediately, TFE was charged into the autoclave, the pressure in the system was set to 2.70 MPaG, stirring was resumed, and the reaction was continued. At the same time, the aqueous solution D obtained in Preparation Example 1 was continuously charged into the autoclave. When 680 g of TFE was charged, stirring was stopped, and the pressure in the system was reduced to atmospheric pressure. By the end of the reaction, 56.0 g of an aqueous potassium permanganate solution and 26.2 g of aqueous solution D were charged. The aqueous dispersion was taken out and cooled, and the paraffin wax was separated to obtain an aqueous PTFE dispersion. The pH of the obtained aqueous PTFE dispersion was 8.8, the solid content was 27.1 mass%, and the primary particle size was 220 nm.

[0186] The resulting PTFE aqueous dispersion was diluted with deionized water to a solids concentration of 13% by mass, and the mixture was vigorously stirred in a container equipped with a stirrer to solidify, after which the water was filtered off to obtain a wet powder. The resulting wet powder was dried at 240°C for 18 hours to obtain PTFE-3. The resulting PTFE-3 had an HFP content of 0.002% by mass and a standard specific gravity of 2.170.

[0187] The following procedures were used to prepare mixture sheets and evaluate mixture sheets and batteries in the examples and comparative examples. (Preparation of Positive Electrode Mixture Sheet) The active material and conductive additive were weighed, placed in a V-type mixer, and mixed at 37 rpm for 10 minutes to obtain a mixture consisting of the active material and conductive additive. Next, the mixture and a compound (any of Compounds 1-1 to 1-7, 2-1, or 2-2) were added, placed in a high-speed fluid mixer, and processed at 200 rpm for 1 minute to disperse the mixture. Then, a weighed binder (fibrillar resin: PTFE powder) was added to the mixture and thoroughly cooled in a constant-temperature bath at 5 °C. The mixture consisting of the active material, conductive additive, binder, and compound was placed in a high-speed fluid mixer and homogenized by processing at 1500 rpm for 3 minutes. The mixture was then sufficiently heated in a constant temperature bath at 80 ° C., and then processed in a high-speed fluid mixer at 2500 rpm for 8 minutes to promote fibrillation, thereby obtaining an electrode mixture. The electrode mixture was placed in a rolling mill in which metal rolls were arranged in parallel and could rotate at different peripheral speeds, to obtain an electrode mixture sheet (temperature: 60 ° C., left roll rotation speed: 1 m / min, right roll rotation speed: 0.8 m / min). The obtained mixture sheet was again placed in the rolling mill and rolled to obtain an electrode mixture sheet with stronger sheet strength. The electrode mixture sheet was then placed in a roll press, and the gap was adjusted. The final thickness of the positive electrode mixture layer was adjusted to 80 μm. Table 1 shows the material types and composition ratios (mass ratios). All of the obtained electrode mixture sheets were free-standing films.

[0188] (Measurement of strength of positive electrode mixture sheet) The positive electrode mixture sheet was cut out to prepare a 4 mm wide strip-shaped test piece. Measurement was performed using a tensile tester (AGS-100NX manufactured by Shimadzu Corporation) at a speed of 100 mm / min. The distance between chucks was 40 mm. Displacement was applied until breakage, and the maximum stress measured was taken as the strength of each sample. Comparative Example A-1 was used in Table 2, Comparative Example B-1 in Table 3, and Comparative Example C-1 in Table 4, all of which were compared as 100. The samples were ranked from A to E in order of high tensile strength and good electrode strength. A: 150 or more B: 130 to 149 C: 110 to 129 D: 95 to 109 E: Less than 95

[0189] (Preparation of Positive Electrode) The above positive electrode mixture sheet was bonded to 20 μm aluminum foil as follows. For the adhesive, a slurry prepared by dissolving polyvinylidene fluoride (PVDF) in N-methylpyrrolidone (NMP) and dispersing carbon black at an 80:20 ratio was used. The above adhesive was applied to the aluminum foil and dried on a hot plate at 120 ° C. for 15 minutes to form a current collector with an adhesive layer. Thereafter, the positive electrode mixture sheet was placed on the current collector with the adhesive layer, and the positive electrode mixture sheet and current collector were bonded together using a roll press heated to 100 ° C. The sheet was then cut to the desired size and tabbed to form a positive electrode.

[0190] (Preparation of Negative Electrode) 98 parts by mass of a carbonaceous material (graphite) was mixed with 1 part by mass of an aqueous dispersion of sodium carboxymethyl cellulose (concentration of sodium carboxymethyl cellulose: 1% by mass) and 1 part by mass of an aqueous dispersion of styrene-butadiene rubber (concentration of styrene-butadiene rubber: 50% by mass) as a thickener and binder, and the mixture was mixed in a disperser to form a slurry. The resulting slurry was applied to a copper foil with a thickness of 10 μm, dried, rolled in a press, cut to the desired size, and tabbed to form a negative electrode.

[0191] (Preparation of Electrolyte Solution) As an organic solvent, a mixed solvent of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) (EC:EMC = 30:70 (volume ratio)) was weighed into a sample bottle, and 1 mass % each of fluoroethylene carbonate (FEC) and vinylene carbonate (VC) was dissolved therein to prepare a mixed solution. LiPF was added to this mixed solution so that the concentration in the electrolyte solution was 1.1 mol / L. ６ The salts were mixed at 23° C. to obtain a non-aqueous electrolyte solution.

[0192] (Preparation of Aluminum Laminated Cell) The above positive electrode was placed opposite to the negative electrode via a 20 μm-thick microporous polyethylene film (separator), and the nonaqueous electrolyte solution obtained above was poured into the cell. After the nonaqueous electrolyte solution had sufficiently permeated the separator and the like, the cell was sealed, pre-charged, and aged to prepare a lithium ion secondary battery.

[0193] <Battery Evaluation> The lithium-ion secondary batteries manufactured as described above were subjected to constant-current-constant-voltage charging (hereinafter referred to as CC / CV charging) (0.1 C cut) at 45°C with a current equivalent to 0.33 C up to 4.25 V, and then discharged to 3 V at a constant current of 0.33 C. This constituted one cycle, and the initial discharge capacity was determined from the discharge capacity at the third cycle. The determined initial discharge capacities (initial capacities) were ranked by relative evaluation. Comparative Example A-1 was used in Table 2, Comparative Example B-1 in Table 3, and Comparative Example C-1 in Table 4, with the score set to 100. ◎: 110 or more ○: 105 to 109 △: 95 to 104 ×: less than 95 Next, the batteries for which the initial discharge capacity evaluation had been completed were again subjected to CC / CV charging (0.1 C cut) at 45°C up to 4.3 V, and the battery volume was determined by the Archimedes method. After determining the battery volume, the batteries were stored at a high temperature of 60°C for 30 days. After the high-temperature storage, the battery was sufficiently cooled and then the volume of the battery was determined at 25°C, and the amount of gas generated was calculated from the difference in volume between the battery before and after the storage test. The calculated amounts of gas generated were ranked by relative evaluation. In Table 2, Comparative Example A-1, in Table 3, and in Table 4, Comparative Example B-1, were set to 100 for comparison. ◎: Less than 80 ○: 80 to 89 △: 90 to 109 ×: 110 or more

[0194]

[0195]

[0196]

[0197]

Claims

1. A composite material for electrochemical devices, comprising a fluoropolyether, a fibrillating resin and an electrochemical device material.

2. The mixture for electrochemical devices according to claim 1, wherein the fluoropolyether is at least one of the fluoropolyethers represented by the following formulas (1) to (4): (1) R １ -O-Ra １ -Rb １ -O-Ra １ -R １ (2) R ２ -Rb ２ -O-Ra ２ -Rb ２ -R ２ (3) R ３ -Rb ３ -O-Ra ３ -R ３ (4) R ４ -Rb ４ -R ４ (In the formula, Ra １ ~Ra ３ are each independently a polyoxyalkylene group containing 4 to 50 oxyalkylene units not containing fluorine, １ ~Ra ３ Each oxyalkylene unit is independently —CH ２ CH ２ O- or -CH ２ CH(J)O-, each J is independently an alkyl group or an aryl group, and Rb １ ~Rb ４ R is each independently a fluoropolyether group represented by the following formula (5): １ ~R ３ are each independently a hydrogen atom, a hydroxyl group, a fluorine atom, an alkyl group having 1 to 3 carbon atoms, an aryl group, a carboxylic acid group, or a fluoroalkyl group having 1 to 3 carbon atoms; R ４ are each independently a fluorine atom, a hydrogen atom, a hydroxyl group, an aldehyde group, a carboxylic acid group, an alkyl ester group having 1 to 10 carbon atoms, an amide group which may have a substituent, or an amino group which may have a substituent. １ -Rf-O-Rf ２ - (wherein, Rf １ and Rf ２ are each independently an alkylene group having 1 to 16 carbon atoms which may be substituted by a fluorine atom, and Rf is a divalent fluoropolyether group.

3. The above Ra １ ~Ra ３ is each independently a polyoxyalkylene group represented by the following formula (Ra-I): -(CH ２ CH ２ O)r(CH ２ CH (CH ３ )O)s(CH ２ CH (CH ２ CH ３ )O)t(CH ２ CH(Ph)O)u- (wherein r, s, t and u are each independently an integer of 0 or 1 or more, and r+s+t+u is 4 to 50.) 4. The above Ra １ ~Ra ３ The mixture for electrochemical devices according to claim 2 or 3, wherein the number average molecular weight of is 40 to 4,000.

5. The mixture for electrochemical devices according to any one of claims 2 to 4, wherein each Rf is independently a fluoropolyether group represented by the following formula (Rf-I): Formula (Rf-I): -(OC ６ F １２ ) a-(OC ５ F １０ ) b-(OC ４ F ８ )c-(OC ３ Rc ６ ) d-(OC ２ F ４ ) e-(OCF ２ )f- (In the formula, Rc is each independently a hydrogen atom, a fluorine atom or a chlorine atom; a, b, c, d, e and f are each independently an integer from 0 to 200; the sum of a, b, c, d, e and f is 1 or more; the order of the repeating units to which a, b, c, d, e or f is assigned is arbitrary; and when all Rc are hydrogen atoms or chlorine atoms, at least one of a, b, c, e and f is 1 or more.) 6. The mixture for electrochemical devices according to any one of claims 2 to 5, wherein each Rf is independently a group represented by the following formula (Rf-II) or the following formula (Rf-I-II): Formula (Rf-II): -(OC ３ F ６ ) d-(OC ２ F ４ )e- (wherein, d is an integer of 1 to 200, and e is 0 or 1.) Formula (Rf-I-II): -(OC ４ F ８ )c-(OC ３ F ６ ) d-(OC ２ F ４ ) e-(OCF ２ )f- (In the formula, c and d each independently represent an integer of 0 to 30, e and f each independently represent an integer of 1 to 200, the sum of c, d, e and f is 2 or more, and the order of each repeating unit to which c, d, e or f is added is arbitrary.) 7. The above R １ ~R ３ The mixture for electrochemical devices according to any one of claims 2 to 6, wherein each of the groups independently represents a methyl group, an ethyl group, a trifluoromethyl group, or a pentafluoroethyl group.

8. The mixture for electrochemical devices according to any one of claims 1 to 7, wherein the fibrillar resin is polytetrafluoroethylene.

9. The mixture for electrochemical devices according to any one of claims 1 to 8, wherein the electrochemical device material is an electrode active material.

10. The mixture for electrochemical devices according to any one of claims 1 to 9, wherein the fluoropolyether is liquid at any temperature between 25°C and 80°C.

11. The mixture for electrochemical devices according to any one of claims 1 to 10, wherein the content of the polyalkylene oxide represented by the following formula (6) is less than 20 mass %. (6) R １Ｂ - (OCHR １Ａ (CH ２ ) jCHR ２Ａ ) n-OR ２Ｂ (In the formula, R １Ａ and R ２Ａ are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, j is an integer of 0 or 1 to 2, and R １Ｂ and R ２Ｂ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and n is an integer of 5 to 1000.

12. The mixture for electrochemical devices according to any one of claims 1 to 11, further comprising a conductive assistant.

13. A mixture sheet for electrochemical devices comprising the mixture for electrochemical devices according to any one of claims 1 to 12.

14. An electrochemical device using the composite sheet for electrochemical devices according to claim 13.

15. A method for producing a composite sheet for electrochemical devices, comprising: a step (1) of mixing a fluoropolyether, a fibrillar resin, and an electrochemical device material; and a step (2) of rolling the composite sheet for electrochemical devices obtained in the step (1) into a sheet.

16. The method according to claim 15, wherein said fibrillar resin is polytetrafluoroethylene.

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