Electrode assembly, battery cell, battery, and manufacturing device and method for electrode assembly

1. An electrode assembly, comprising a negative electrode plate and a positive electrode plate, the negative electrode plate and the positive electrode plate forming a bending region by winding or folding;

the positive electrode plate comprising a plurality of bending portions located in the bending region, the bending portion comprising a positive electrode current collecting layer and a positive active substance layer, and at least one side surface of the positive electrode current collecting layer being provided with the positive active substance layer in a thickness direction of the positive electrode plate;

wherein, at least one positive active substance layer is provided with a barrier layer, at least a part of the barrier layer is intercalated in the positive active substance layer provided with the barrier layer, and coats at least a part of particles in the positive active substance layer, to prevent the particles from releasing an ion to the negative electrode plate;

wherein the electrode assembly further comprises a separator for separating the positive electrode plate from the negative electrode plate; and the barrier layer is connected to the separator; and

wherein the separator is provided with a plurality of through holes; and

the barrier layer partially extends into the through hole and is connected to a hole wall of the through hole.

2. The electrode assembly according to claim 1 , wherein the positive electrode current collecting layer is provided with the positive active substance layer on an inner side surface in the thickness direction; and the positive active substance layer located on the inner side surface of at least one bending portion is provided with the barrier layer.

3. The electrode assembly according to claim 1 , wherein the positive electrode current collecting layer is provided with the positive active substance layer on an outer side surface in the thickness direction; and the positive active substance layer located on the outer side surface of at least one bending portion is provided with the barrier layer.

4. The electrode assembly according to claim 1 , wherein the positive electrode current collecting layer is provided with the positive active substance layer on both the inner side surface and the outer side surface in the thickness direction, and the positive active substance layer located on the inner side surface and the positive active substance layer located on the outer side surface of at least one bending portion are both provided with the barrier layer.

5. The electrode assembly according to claim 1 , wherein a depth of a part of the barrier layer extending into the through hole is no less than 3 micrometers.

6. The electrode assembly according to claim 1 , wherein both ends of the barrier layer extending along a bending direction of the bending portion are located in the bending region.

7. The electrode assembly according to claim 1 , wherein the electrode assembly comprises a straight region connected to the bending region;

both ends of the barrier layer extending along a bending direction of the bending portion are located in the straight region, or, one end of the barrier layer extending along the bending direction of the bending portion is located in the straight region, and the other end is located in the bending region.

8. The electrode assembly according to claim 1 , wherein the barrier layer is a glue layer.

9. A battery cell, comprising a shell and the electrode assembly according to claim 1 ;

the electrode assembly being accommodated in the shell.

10. A battery, comprising a box body, and the battery cell according to claim 9 ;

the battery cell being accommodated in the box body.

11. A power consumption device, comprising the battery cell according to claim 9 .

12. A manufacturing method for the electrode assembly of claim 1 , the manufacturing method comprising:

providing a positive electrode plate, a negative electrode plate, a separator and a barrier layer;

winding or folding the positive electrode plate and the negative electrode plate, to form a bending region;

wherein, the positive electrode plate comprises a plurality of bending portions located in the bending region, the bending portion comprises a positive electrode current collecting layer and a positive active substance layer, at least one side surface of the positive electrode current collecting layer is provided with the positive active substance layer on in a thickness direction of the positive electrode plate;

at least one positive active substance layer is provided with the barrier layer, at least a part of the barrier layer is intercalated in the positive active substance layer provided with the barrier layer, and coats at least a part of particles in the positive active substance layer, to prevent the particles from releasing an ion to the negative electrode plate; and

the separator is configured to separate the positive electrode plate from the negative electrode plate; and the barrier layer is connected to the separator.

13. The manufacturing method according to claim 12 , wherein the manufacturing method further comprises:

before winding or folding the positive electrode plate and the negative electrode plate, fixing the barrier layer on the positive electrode plate, so that at least a part of the barrier layer is intercalated in the positive active substance layer of the positive electrode plate.

14. The manufacturing method according to claim 12 , wherein a separator for separating the positive electrode plate from the negative electrode plate is provided, and the positive electrode plate, the separator and the negative electrode plate are wound or folded to form the bending region.

15. The manufacturing method according to claim 14 , wherein the manufacturing method further comprises:

heating the barrier layer, making the barrier layer in a viscous state, so that the barrier layer is bonded to the separator and infiltrated to a through hole of the separator.

16. An electrode assembly, comprising a negative electrode plate and a positive electrode plate, the negative electrode plate and the positive electrode plate forming a bending region by winding or folding;

the positive electrode plate comprising a plurality of bending portions located in the bending region, the bending portion comprising a positive electrode current collecting layer and a positive active substance layer, and at least one side surface of the positive electrode current collecting layer being provided with the positive active substance layer in a thickness direction of the positive electrode plate;

wherein, at least one positive active substance layer is provided with a barrier layer, at least a part of the barrier layer is intercalated in the positive active substance layer provided with the barrier layer, and coats at least a part of particles in the positive active substance layer, to prevent the particles from releasing an ion to the negative electrode plate;

wherein the electrode assembly further comprises a separator for separating the positive electrode plate from the negative electrode plate; and the barrier layer is connected to the separator; and

wherein the barrier layer comprises an intercalating portion and a connection portion;

the intercalating portion is intercalated in the positive active substance layer provided with the barrier layer, the connection portion is connected to the separator, and the connection portion is located between the separator and the positive active substance layer provided with the barrier layer.

17. The electrode assembly according to claim 16 , wherein a thickness of the connection portion is no more than 20 micrometers.

18. A battery cell, comprising a shell and the electrode assembly according to claim 16 ;

the electrode assembly being accommodated in the shell.

19. An electrode assembly, comprising a negative electrode plate and a positive electrode plate, the negative electrode plate and the positive electrode plate forming a bending region by winding or folding;

the positive electrode plate comprising a plurality of bending portions located in the bending region, the bending portion comprising a positive electrode current collecting layer and a positive active substance layer, and at least one side surface of the positive electrode current collecting layer being provided with the positive active substance layer in a thickness direction of the positive electrode plate;

wherein, at least one positive active substance layer is provided with a barrier layer, at least a part of the barrier layer is intercalated in the positive active substance layer provided with the barrier layer, and coats at least a part of particles in the positive active substance layer, to prevent the particles from releasing an ion to the negative electrode plate; and

wherein the positive electrode plate and the negative electrode plate form a winding structure by winding, and the winding structure comprises the bending region;

an electrode plate of the innermost side of the bending region is the negative electrode plate, and a bending portion of the innermost side of the bending region is provided with the barrier layer.

20. A battery cell, comprising a shell and the electrode assembly according to claim 19 ;

the electrode assembly being accommodated in the shell.