Power storage element and method for manufacturing same

A method of manufacturing a power storage element, the method comprising:

• providing sheets of a positive electrode body, a negative electrode body, and two separators;
• laminating the sheets, each having slits that penetrate in a thickness direction, to form a sheet-like electrode laminate including a unit electrode layer in which one of the positive electrode body and the negative electrode body is arranged between the two separators, and the other of the positive electrode body and the negative electrode body is arranged on an outer side of one of the two separators;
• winding the electrode laminate in an extension direction of the electrode laminate to form an electrode member including a plurality of unit electrode layers laminated in a lamination direction, wherein the slits of the respective sheets of the plurality of unit electrode layers in the electrode member are aligned to form a through hole penetrating in the lamination direction;
• setting a positive electrode-body exposing edge part and a negative electrode-body exposing edge part in the positive electrode body and the negative electrode body, respectively, wherein the positive electrode-body exposing edge part and the negative electrode-body exposing edge part are exposed from the electrode member in an opposition direction perpendicular to the lamination direction and the extension direction;
• providing an outer collector including a pair of outer opposing walls facing each other with a gap therebetween and an inner collector disposed on an inner side with respect to the pair of outer opposing walls and including a pair of inner opposing walls facing each other with a gap therebetween in the opposition direction of the pair of outer opposing walls;
• and
• assembling the power storage element such that the positive electrode-body exposing edge part is placed in electrical contact with one of the pair of outer opposing walls and the pair of inner opposing walls, and the negative electrode-body exposing edge part is placed in electrical contact with the other of the pair of outer opposing walls and the pair of inner opposing walls to put together the electrode member, the outer collector, and the inner collector,
• wherein in the power storage element, the through hole receives the inner opposing walls in a fitted manner,
• the through hole is shaped as an elongated hole along the extension direction, and
• the through hole has a larger length in the extension direction than a length of the inner opposing walls in the extension direction.