FILM-ENCLOSED ELECTRIC DEVICE AND PRODUCTION METHOD THEREFOR

摘要

A releasing pressure and a pressure releasing position, when an enclosing film is expanded by gas produced at an abnormal time, are easily and positively set. A film-enclosed battery (1) has a battery element (2) and two enclosing films (4, 5) for sealing the battery element (2). The enclosing films (4, 5) include heat-fusion resin layers and air-impermeable layers, and the heat-fusion resin layers facing each other hold the battery element (2) and seal the battery element (2) when their peripheral edges are heat-fused. A cross-linking structure (8) formed by cross-linking heat-fusion resin layers is formed in one of the enclosing films (4, 5) so that a region in part of a heat-fusion-formed portion (6) has a portion exposed to a battery element housing unit and another portion in contact with outside air.