Electrode assembly, secondary battery, battery pack and device

1. An electrode assembly for a secondary battery, the electrode assembly comprising:

an electrode unit comprising an electrode body and an electrode terminal part electrically connected with the electrode body; and

a first insulating film for being wound around the electrode unit, the first insulating film comprising a connection part and an extension part connected with each other, the connection part being provided with an adhesive area for connecting with the electrode terminal part, the extension part being a part of the first insulating film extending beyond an end face of the electrode terminal part, and at least part of the extension part being provided with a non-adhesive area adjacent to a side where the electrode terminal part is located.

2. The electrode assembly of claim 1 , wherein the non-adhesive area covers the extension part.

3. The electrode assembly of claim 2 , wherein the non-adhesive area extends from the extension part to the connection part.

4. The electrode assembly of claim 1 , wherein the connection part comprises a first portion and a second portion connected with each other, the first portion is used to cover an outer peripheral surface of the electrode terminal part, the second portion is used to cover at least a part of an outer peripheral surface of the electrode body, and each of the first portion and the second portion is provided with the adhesive area.

5. The electrode assembly of claim 4 , wherein the second portion completely covers the outer peripheral surface of the electrode body.

6. The electrode assembly of claim 1 , further comprising a second insulating film for being wound around an outer peripheral surface of the electrode body, a surface of the second insulating film is provided with adhesive glue, and the second insulating film extends to an outer periphery of the electrode terminal part and does not extend beyond the end face of the electrode terminal part.

7. The electrode assembly of claim 6 , wherein the second insulating film is partially laminated with the first insulating film.

8. The electrode assembly of claim 6 , wherein the second insulating film and the first insulating film abut with each other at a boundary between the electrode terminal part and the electrode body.

9. The electrode assembly of claim 6 , wherein the second insulating film and the first insulating film abut with each other on the outer peripheral surface of the electrode terminal part.

10. The electrode assembly of claim 7 , wherein the second insulating film extends to an outer periphery of the electrode terminal part and is partially laminated with the first insulating film.

11. The electrode assembly of claim 1 , wherein the first insulating film comprises a substrate, an adhesive layer is provided on a portion of the substrate to form the adhesive area, and at least a portion of the substrate corresponding to the extension part is not provided with the adhesive layer to form the non-adhesive area.

12. A secondary battery, comprising:

a housing with an opening;

an end cover for covering the opening and enclosing an accommodation space with the housing; and

the electrode assembly of claim 1 located in the accommodation space.

13. The secondary battery of claim 12 , wherein a separator is provided on a side of the end cover facing the electrode assembly, the separator comprises a side wall and a receiving space enclosed by the side wall, and the extension part is located in the receiving space.

14. A device comprising the secondary battery of claim 12 , the secondary battery being used to provide electrical energy.