| 摘要 |
PURPOSE:To obtain a long lived battery preventing the exposure of an metallic part caused by pin holes or cracks by making a synthetic resin film to be laminated on the inside surface of a metallic battery case plate have a multilayered structure of resins of different softening points and disposing a layer of a higher softening point on the surface of the metallic plate. CONSTITUTION:A heat adhesive synthetic film 2 of PE, PP, etc., is laminated on the inner surface of a battery case plate acting also as a terminal of the battery, made of a metallic plate such as copper or stainless steel, through a protective film 2', which has higher softening point. When the metallic battery case plates laminated with a synthetic resin films are put opposingly to each other to fuse the films under pressure and heat, the synthetic film 2 which has higher melting point is disposed closer to the battery case plate. Thereby the short-circuit between two battery case plates 1 acting also as terminals of the battery is not easily caused and the battery case plate can be protected from the corrosion caused by an electrolytic solution even when pin holes or cracks are produced in the outside fused film. |
