Film including a resin layer containing polyethylene, polypropylene, and a compatibilizer for a terminal

1 . A resin film for a terminal for covering an outer peripheral surface of part of a metal terminal that constitutes a power storage device, comprising:

a resin layer containing a polyethylene (A), and

a compatibilizer (B) that has an amorphous unit and has a region that is compatible with the polyethylene (A) and a region that is compatible with polypropylene,

wherein a mass ratio of the polyethylene (A) to the compatibilizer (B) is 0.15 to 30, and

wherein the resin layer further contains a polypropylene (C).

2 . The resin film for a terminal of claim 1 , wherein the compatibilizer (B) is a graft copolymer.

3 . The resin film for a terminal of claim 1 , wherein a mass ratio ((A)/(B)) of the polyethylene (A) and the compatibilizer (B) contained in the resin layer is 0.15 to 30.

4 . The resin film for a terminal of claim 1 , wherein the resin layer contains a resin having a polar group.

5 . The resin film for a terminal of claim 1 , wherein the resin film for a terminal comprises three or more layers, and a layer disposed at least on both surfaces of the resin film for a terminal is the resin layer.

6 . The resin film for a terminal of claim 1 , wherein the compatibilizer (B) is a block copolymer.

7 . The resin film for a terminal of claim 1 , wherein a mass ratio ((A)/(B)) of the polyethylene (A) and the compatibilizer (B) contained in the resin layer is 0.5 to 10.

8 . The resin film for a terminal of claim 1 , wherein a mass ratio ((A)/(B)) of the polyethylene (A) and the compatibilizer (B) contained in the resin layer is 1.0 to 5.

9 . The resin film for a terminal of claim 1 , wherein a content of the region that is compatible with the polyethylene (A) and a content of the region that is compatible with polypropylene are in ratio of 1/9 to 9/1.

10 . The resin film for a terminal of claim 1 , wherein a content of the region that is compatible with the polyethylene (A) and a content of the region that is compatible with polypropylene are in ratio of 2/8 to 8/2.

11 . The resin film for a terminal of claim 1 , wherein a content of the region that is compatible with the polyethylene (A) and a content of the region that is compatible with polypropylene are in ratio of 3/7 to 7/3.

12 . The resin film for a terminal of claim 1 , wherein the polyethylene (A) has a melting point from 80 to 135° C.

13 . The resin film for a terminal of claim 1 , wherein the resin layer further contains a polypropylene (C) and (B) is a polypropylene-polyethylene block.

14 . The resin film for a terminal of claim 6 , wherein the resin layer further contains a polypropylene (C) and (B) is an ethylene-ethylene-butylene block copolymer.

15 . The resin film for a terminal of claim 1 , wherein the polyethylene (A) is a modified polyethylene having a polar group.

16 . The resin film for a terminal of claim 1 , wherein the polar group is an acid anhydride group.

17 . The resin film for a terminal of claim 1 , wherein the polyethylene (A) is an acid-modified polyethylene.

18 . A power storage device, comprising:

a power storage device body;

a metal terminal electrically connected to the power storage device body;

an exterior material that sandwiches the metal terminal and accommodates the power storage device body; and

a resin film disposed between the metal terminal and the exterior material so as to cover an outer peripheral surface of part of the metal terminal;

wherein the resin film comprises:

a resin layer containing a polyethylene (A), and

a compatibilizer (B) that has an amorphous unit and has a region that is compatible with the polyethylene (A) and a region that is compatible with polypropylene; wherein a mass ratio of the polyethylene (A) to the compatibilizer (B) is 0.15 to 30, and wherein the resin layer further contains a polypropylene (C);

and

wherein the exterior material has a sealant layer containing polypropylene on a surface that makes contact with the resin film for a terminal.