Connection member

1. A connection member configured to electrically connect respective storage elements to each other in a power storage device constituted by a plurality of storage elements, the connection member comprising:

an electrically conductive substrate; and

a plurality of connecting portions configured to connect to electrodes of the respective storage elements, and cut off electric connection with the storage elements by fusing at a time when a current of a predetermined value or more flows therein,

wherein each connecting portion of the plurality of connecting portions is formed by performing punching along a punching axis on the electrically conductive substrate,

wherein each connecting portion comprises:

a first extension portion extending in a first direction perpendicular to the punching axis;

a second extension portion extending from the first extension portion and extending, in a second direction perpendicular to the punching axis; and

a third extension portion extending from the second extension portion in a direction parallel to the first direction,

a first bent portion that is part of the first extension portion and is bent so as to ascend or descend with respect to other portions of the first extension portion along the punching axis, and extend in the first direction, and

a second bent portion that is part of the second extension portion and is bent so as to ascend or descend with respect to other portions of the second extension portion along the punching axis, and extend in the second direction

wherein the first extension portion is offset with respect to at least one of the second extension portion or the third extension portion, along the punching axis,

wherein the first and second bent portions are formed by bending the first extension portion and the second extension portion in the punching axis along their respective extending directions, and

wherein the first bent portion and the second bent portion each have a planar shape that is straight.

2. The connection member according to claim 1 ,

wherein the first extension portion is offset with respect to the second extension portion and the third extension portion, along the punching axis.

3. The connection member according to claim 1 , wherein respective bending directions of the first and second bent portions are the same in the punching axis.

4. The connection member according to claim 1 , wherein respective bending directions of the first and second bent portions are different from each other in the punching axis.

5. The connection member according to claim 1 , wherein:

each of the plurality of storage elements is a cylindrical storage element having a longitudinal direction;

the plurality of storage elements are arranged in-line so that positive electrodes or negative electrodes of each of the plurality of storage elements all face the same direction; and

the connection member is connected to respective negative electrodes of each of the plurality of storage elements.

6. A power storage device comprising:

the connection member according to claim 1 ; and

wherein the plurality of storage elements are electrically connected in parallel with each other by the connection member.

7. The connection member according to claim 1 , wherein the first extension portion and the second extension portion are arranged at a right angle with respect to each other, and the second extension portion and the third extension portion are arranged at a right angle with respect to each other.

8. The connection member according to claim 1 , wherein the first, second, and third extension portions do not overlap each other along the punching axis.

9. A connection member configured to electrically connect respective storage elements to each other in a power storage device constituted by a plurality of storage elements, the connection member comprising:

an electrically conductive substrate; and

a plurality of connecting portions configured to connect to electrodes of the respective storage elements, and cut off electric connection with the storage elements by fusing at a time when a current of a predetermined value or more flows therein, wherein

each connecting portion of the plurality of connecting portions is formed by performing punching along a punching axis on the electrically conductive substrate, and

wherein each connecting portion comprises:

a first extension portion;

a second extension portion extending from the first extension portion;

a third extension portion extending from the second extension portion: and

a fourth extension portion,

a triangular-shaped first bent portion that bridges the first and second extension portions and is bent towards the punching axis, and

a triangular-shaped second bent portion that bridges the second and third extension portions and is bent towards the punching axis,

a rectangular-shaped third bent portion that connects the third and fourth extension portions,

wherein the fourth extension portion is offset along the punching axis with respect to at least one of the first extension portion, the second extension portion, and the third extension portion, and

wherein the triangular-shaped first bent portion and the triangular-shaped second bent portion each have a planar shape that extends straight.

10. The connection member according to claim 9 , wherein the first extension portion and the second extension portion are arranged at a right angle with respect to each other, and the second extension portion and the third extension portion are arranged at a right angle with respect to each other.

11. The connection member according to claim 9 , wherein the first, second, third, and fourth extension portions do not overlap each other along the punching axis.