Binder composition for batteries, slurry for battery electrodes, solid electrolyte composition, electrode, and all-solid-state battery

1. A binder composition for batteries, comprising:

(A) a polymer that comprises at least one structural unit selected from structural units represented by formulae (a1) to (a5), and (f) a functional group comprising a nitrogen atom, an oxygen atom, a silicon atom, a germanium atom, a tin atom or a combination thereof; and

(B) a liquid medium,

the polymer (A) having a solubility of no less than 5 g in 100 g of cyclohexane at 25° C. and 1 atm,

wherein, in the formulae (a1) to (a5), R A1 to R F5 are each independently a hydrogen atom or a monovalent aliphatic hydrocarbon group having 1 to 18 carbon atoms,

wherein the polymer (A) comprises at least one structural unit selected from the structural units represented by the formulae (a1) and (a2), and a total content of the structural units represented by the formulae (a1) and (a2) is no less than 60% by mol with respect to a total content of the structural units represented by the formulae (a1) to (a5).

2. The binder composition according to claim 1 , wherein the polymer (A) is obtained by reacting an active end of a polymer comprising at least one structural unit selected from the structural units represented by the formulae (a1) to (a5), with (m) a denaturant comprising a nitrogen atom, an oxygen atom, a silicon atom, a germanium atom, a tin atom or a combination thereof to form a bond.

3. The binder composition according to claim 2 , wherein the denaturant (m) is represented by formula (x):

R 1 4-n1 MX 1 n1   (x)

wherein, in the formula (x), R 1 is a hydrogen atom or a monovalent hydrocarbon group; M is a silicon atom, a germanium atom, or a tin atom; X 1 is a halogen atom or an alkoxy group; n1 is an integer of from 2 to 4; and wherein, in a case in which R 1 is present in a plurality of number, the plurality of R 1 s are each identical or different, and in a case in which X 1 is present in a plurality of number, the plurality of X 1 s are each identical or different.

4. The binder composition according to claim 1 , wherein the polymer (A) is represented by formula (P):

L a MY 4-a   (P)

wherein, in the formula (P), L is a polymer chain comprising at least one structural unit selected from structural units represented by the formulae (a1) to (a5); M is a silicon atom, a germanium atom, or a tin atom; Y is a hydrogen atom, a monovalent hydrocarbon group, a halogen atom, or an alkoxy group; a is an integer of from 2 to 4; and wherein, in a case in which L is present in a plurality of number, the plurality of Ls are each identical or different, and in a case in which Y is present in a plurality of number, the plurality of Ys are each identical or different.

5. The binder composition according to claim 1 , wherein a content of the functional group (f) in the polymer (A) is no less than 0.0005 mol/kg and no greater than 0.2 mol/kg.

6. The binder composition according to claim 1 , wherein the functional group (f) is an amino group, a hydroxyl group, a carboxyl group, an alkoxysilyl group or a combination thereof.

7. The binder composition according to claim 1 , wherein a ratio of a weight average molecular weight to a number average molecular weight of the polymer (A) is no greater than 3.

8. The binder composition according to claim 1 , wherein the polymer (A) is obtained by living anionic polymerization.

9. The binder composition according to claim 1 , wherein the liquid medium (B) is a nonpolar organic liquid medium.

10. A slurry for battery electrodes, comprising:

an electrode active material; and

the binder composition according to claim 1 .

11. A solid electrolyte composition, comprising:

a solid electrolyte material; and

the binder composition according to claim 1 .

12. An electrode, comprising:

a current collector and an electrode layer laminated on at least a part of the current collector,

wherein the electrode layer is formed from the slurry according to claim 10 .

13. An all-solid-state battery, comprising:

a pair of electrodes which are disposed such that the electrode layers are opposed, wherein each of the pair of electrodes is the electrode according to claim 12 ; and

a solid electrolyte layer disposed between the pair of electrodes.