Solid electrolyte composition, binder for all-solid-state secondary batteries, and electrode sheet for batteries and all-solid-state secondary battery each using said solid electrolyte composition

1. A solid electrolyte composition comprising:

an inorganic solid electrolyte having conductivity of an ion of metal belong to Group 1 or 2 in the periodic table; and

a high polymer binder,

wherein the high polymer binder is formed of a polymer having a hard segment and a soft segment, and

wherein the hard segment forming the high polymer binder contains at least any one bond of an amide bond, an urea bond, an urethane bond, and an imide bond, and the polymer forming the high polymer binder has at least any one of repeating structures expressed by Formulae (II-1) to (II-5) of Group II below, as the soft segment,

in Formulae (II-1), and (II-3) to (II-5), R 21 represents a hydrogen atom or an alkyl group, R 22 represents a substituent group which contains a polyalkylene oxide chain, a polycarbonate chain, or a polyester chain and of which a weight average molecular weight is 200 to 200,000, R 23 represents a linking group which contains a polyalkylene oxide chain, a polycarbonate chain, or a polyester chain and of which a weight average molecular weight is 200 to 200,000, and * represents a bonding position, and

in Formulae (II-2), R 23 represents a linking group which contains a polycarbonate chain and of which a weight average molecular weight is 200 to 200,000, and * represents a bonding position.

2. The solid electrolyte composition according to claim 1 ,

wherein the polymer forming the high polymer binder includes at least any one of an alcoholic hydroxyl group, a phenolic hydroxyl group, a mercapto group, a carboxy group, a sulfo group, a sulfonamide group, a phosphate group, a cyano group, an amino group, a zwitterion-containing group, a metal hydroxide group, and a metal alkoxide group.

3. The solid electrolyte composition according to claim 1 ,

wherein the polymer forming the high polymer binder includes a carbon-carbon unsaturated group.

4. The solid electrolyte composition according to claim 3 ,

wherein the carbon-carbon unsaturated group is expressed by Formula (1) or (2) below,

in Formulae (1) and (2), each of R 1 and R 5 independently represents an oxygen atom or NR N , R N represents a hydrogen atom or an alkyl group, each of R 2 to R 4 and R 6 to R 10 independently represents a hydrogen atom or an alkyl group, and * represents a bonding position.

5. The solid electrolyte composition according to claim 1 ,

wherein the polymer forming the high polymer binder has at least any one of repeating structures expressed by Formulae (I-1) to (I-5) of Group I below, as the hard segment,

in Formulae (I-1) to (I-5), each of R 11 and R 12 independently represents a bivalent linking group which is an alkylene group, an arylene group, or a combination thereof, R 13 represents an alkyl group, an alkenyl group, an aryl group, or an aralkyl group, R 14 represents an aromatic or aliphatic tetravalent linking group, R a represents a hydrogen atom or an alkyl group, and * represents a bonding position.

6. The solid electrolyte composition according to claim 1 , further comprising:

an electrode active substance.

7. The solid electrolyte composition according to claim 1 ,

a ratio of a total mass of the inorganic solid electrolyte and an electrode active substance contained if necessary is in a range of 1,000 to 1 with respect to a mass of the high polymer binder.

8. The solid electrolyte composition according to claim 1 ,

wherein a molar ratio of the soft segment component to the hard segment component forming the high polymer binder is 1 mol to 10,000 mol with respect to 100 mol of the hard segment component.

9. An electrode sheet for batteries obtained by forming a film by disposing the solid electrolyte composition according to claim 1 on a metal foil.

10. An all-solid-state secondary battery comprising:

a positive electrode active substance layer;

a negative active substance layer; and

a solid electrolyte layer,

wherein at least any one of the positive electrode active substance layer, the negative active substance layer, and the solid electrolyte layer is formed of the solid electrolyte composition according to claim 1 .

11. The solid electrolyte composition according to claim 1 ,

wherein the polymer forming the high polymer binder has at least any one of repeating structures expressed by Formulae (II-1), (II-3) to (II-5) of Group II.