MANUFACTURING METHOD OF POWER STORAGE DEVICE

A manufacturing method of a power storage device includes: an arrangement step of arranging a first resin member on a first surface of a metal foil and arranging a second resin member on a second surface of the metal foil; and a welding step of arranging a first pressurizing member and a second pressurizing member on a surface on an opposite side of the first resin member and the second resin member, respectively, from a surface on the metal foil side, and irradiating the end portion of the metal foil with an electromagnetic wave from the first pressurizing member side while pressurizing the end portion with the first pressurizing member and the second pressurizing member so as to weld the first resin member and the second resin member to the metal foil such that the end portion of the metal foil is covered.