| 摘要 |
Provided is a highly-reliable power storage device capable of suppressing an increase in the short-circuit area between a positive electrode member and a negative electrode member even when a separator is heated and thus thermally shrunk in a heating test. In the power storage device having a structure in which a power storage element including a laminate and an electrolyte is housed in an exterior body, the laminate being formed by laminating a positive electrode member (11) and a negative electrode member (12) so as to face each other through a separator (13), the separator (13) is formed by welding together, at at least two sides (23a, 23b) that face each other in a plan view, two layers of a sheet material for the separator. The positive electrode member and/or the negative electrode member is housed in the separator and thus the positive electrode member and the negative electrode member are laminated so as to face each other through the separator. The joint strengths by the welding at the two sides (23a, 23b) of the separator (13) are different from each other. |
