Abstract: A positive electrode (110) is a first electrode, and a negative electrode (120) is a second electrode having an area larger than that of the first electrode. A separator (130) is folded and extends through between the positive electrode (110) and the negative electrode (120) adjacent to each other. A folded portion of the separator (130) covers a portion of the negative electrode (120) on the same side in each of a plurality of battery cells (10). Specifically, the folded portion of the separator (130) covers the upper portion of the negative electrode (120) in each of the plurality of battery cells (10).

Abstract: An outer edge of a negative electrode (200) covered with a first adhesive member (410) is substantially aligned with an outer edge of a positive electrode (100) covered with the first adhesive member (410) in a direction from a stacked body (10) toward the first adhesive member (410) or a direction from the first adhesive member (410) toward the stacked body (10). Specifically, the outer edge of the negative electrode (200) covered with the first adhesive member (410) is positioned within a distance equal to or more than 0% and equal to or less than 200% of a thickness of the negative electrode (200) from the outer edge of the positive electrode (100) covered with the first adhesive member (410) in the above direction.

Abstract: A method for manufacturing a flat film-covered battery having a power-generating element formed by stacking a plurality of positive electrodes and negative electrodes with separators interposed therebetween in which the power-generating element is housed together with an electrolytic solution in a flexible film-shaped exterior body. The manufacturing method includes injecting the electrolytic solution into the film-shaped exterior body via an injection port, and then sealing the injection port after the injecting of the electrolytic solution. After the sealing of the injection port, pressurization and pressure release the power-generating element is successively performing such that the power-generating element is subjected to pressurization and then pressure release from outside of the film-shaped exterior body along the thickness direction a plurality of times.