Secondary battery, apparatus containing the secondary battery, method for the preparation of the secondary battery, and binder composition

1. A binder composition comprising a cross-linkable polymer matrix and a cross-linking agent, wherein the cross-linkable polymer matrix comprises one or more of monomer units represented by formula (I), and the cross-linking agent comprises a compound represented by formula (II):

in which

R 1 , R 2 and R 3 are each independently selected from H and straight-chain or branched-chain alkyl groups with 1 to 8 carbon atoms;

R 4 is selected from

and -(R 8 ) a -X

in which

R 7 is selected from H, and substituted or unsubstituted alkyl groups with 1 to 6 carbon atoms; and

a is 0 or 1; the R 8 is selected from phenylene, and substituted or unsubstituted alkylene groups with 1 to 6 carbon atoms, and X is selected from —COOH, —SO 3 H, —SO 2 H, hydroxyl, sulfhydryl, and amino;

R 5 is selected from -(R 2 ) b -Y, b is 0 or 1, R 2 is selected from straight-chain or branched alkylene groups with 1 to 4 carbon atoms, and Y is epoxy group;

R 6 is selected from H and substituted or unsubstituted hydrocarbon groups with 1 to 8 carbon atoms; and

n is an even number greater than 4, 2≤m≤n.

2. The binder composition as claimed in claim 1 , wherein based on the total weight of the crosslinkable polymer matrix and the crosslinking agent, a weight percentage of the crosslinkable polymer matrix is ≥70%.

3. The binder composition as claimed in claim 1 , wherein the binder composition further satisfies one or more of the following (1)-(2):

(1) an aqueous solution of the binder composition with a concentration of 10 wt % has a viscosity of 150 mPa s to 20000 mPa·s;

(2) an aqueous solution of the binder composition with a concentration of 10 wt % has a pH of greater than 7.

4. The binder composition as claimed in claim 2 , wherein the binder composition further satisfies one or more of the following (1)-(2):

(1) an aqueous solution of the binder composition with a concentration of 10 wt % has a viscosity of 150 mPa s to 20000 mPa·s;

(2) an aqueous solution of the binder composition with a concentration of 10 wt % has a pH of greater than 7.

5. A process for the preparation of a secondary battery (5), comprising binding a first substance and a second substance with a binder, the binder comprising a polymer obtained by crosslinking a cross-linkable polymer matrix and a cross-linking agent, the cross-linkable polymer matrix comprises one or more of monomer units represented by formula (I), and the cross-linking agent comprises a compound represented by formula (II):

in which

R 1 , R 2 and R 3 are each independently selected from H and straight-chain or branched-chain alkyl groups with 1 to 8 carbon atoms;

R 4 is selected from

and —(R 8 ) a -X

in which

R 7 is selected from H, and substituted or unsubstituted alkyl groups with 1 to 6 carbon atoms; and

a is 0 or 1; the R 8 is selected from phenylene, and substituted or unsubstituted alkylene groups with 1 to 6 carbon atoms, and X is selected from —COOH, —SO 3 H, —SO 2 H, hydroxyl, sulfhydryl, and amino;

R 5 is selected from -(R 2 ) b -Y, b is 0 or 1, R 2 is selected from straight-chain or branched alkylene groups with 1 to 4 carbon atoms, and Y is epoxy group;

R 6 is selected from H and substituted or unsubstituted hydrocarbon groups with 1 to 8 carbon atoms; and

n is an even number greater than 4, 2≤m≤n,

wherein the polymer has a three-dimensional cross-linked network structure.

6. The binder composition as claimed in claim 1 , wherein R 7 is selected from H, and substituted or unsubstituted alkyl groups with 1 to 4 carbon atoms.

7. The binder composition as claimed in claim 1 , wherein R 8 is selected from phenylene, and substituted or unsubstituted alkylene groups with 1 to 4 carbon atoms, and X is selected from —COOH, and hydroxyl.

8. The binder composition as claimed in claim 1 , wherein m≥3.

9. The binder composition as claimed in claim 1 , wherein based on the total weight of the crosslinkable polymer matrix and the crosslinking agent, a weight percentage of the crosslinkable polymer matrix is from 75% to 95%.

10. The binder composition as claimed in claim 1 , wherein based on the total weight of the crosslinkable polymer matrix and the crosslinking agent, a weight percentage of the crosslinkable polymer matrix is from 85% to 95%.

11. The binder composition as claimed in claim 1 , wherein the binder composition further satisfies one or more of the following (1)-(2):

(1) an aqueous solution of the binder composition with a concentration of 10 wt % has a viscosity of from 600 mPa·s to 4000 mPa·s;

(2) an aqueous solution of the binder composition with a concentration of 10 wt % has a pH of 7.5 to 10.5.

12. The binder composition as claimed in claim 2 , wherein the binder composition further satisfies one or more of the following (1)-(2):

(1) an aqueous solution of the binder composition with a concentration of 10 wt % has a viscosity of from 600 mPa·s to 4000 mPa·s;

(2) an aqueous solution of the binder composition with a concentration of 10 wt % has a pH of 7.5 to 10.5.

13. The process as claimed in claim 5 , wherein R 7 is selected from H, and substituted or unsubstituted alkyl groups with 1 to 4 carbon atoms.

14. The process as claimed in claim 5 , wherein R 8 is selected from phenylene, and substituted or unsubstituted alkylene groups with 1 to 4 carbon atoms, and X is selected from —COOH, and hydroxyl.

15. The process as claimed in claim 5 , wherein m≥3.

16. The process as claimed in claim 5 , wherein the crosslinkable polymer matrix and the crosslinking agent are crosslinked under heating conditions.

17. The process as claimed in claim 16 , wherein the heating is carried out at a temperature of 60° C. to 160° C.