In a power storage module, a side surface of an electrode laminate body has a welded layer where first sealing portions adjacent in a lamination direction are welded. A sealing body has: a side surface (opening wall) provided with a through hole communicating with an internal space; and side surfaces (non-opening walls) lacking the through hole. When viewed from the lamination direction, a width of the welded layer at the opening wall is smaller than a width of the welded layer at the non-opening wall.