A laminate-type power storage element has a flat body and an interior layered flat plate-shaped electrode body. A positive electrode terminal plate is mounted to a positive electrode of the electrode body and is guided outside from a predetermined margin of the body. A negative electrode terminal plate is mounted to a negative electrode of the electrode body and guided in the same direction. A film member spans across both electrode terminal plates. The film member is made by layering an insulating heat-resistant film and an adhesive to thermocompression bond the heat-resistant film to a matter to be adhered to. The film member is thermocompression bonded to the electrode terminal plate at a region facing principal surfaces of the positive and the negative plates, and is thermocompression bondable to the matter to be adhered to in a region that does not face the respective principal surfaces.