| 摘要 |
PURPOSE:To prevent any positional shift between a porous resin film and unwoven cloth, by piling up and punching the porous resin film and unwoven cloth used in a separator and welding together the punched edges of both components. CONSTITUTION:A porous polypropylene film 1a and polypropylene cloth 1b are piled up in this order on a base plate 11 made of modified hard polyethylene and punched by a punch 12. After punching them in this way, the punched edge of the unwoven cloth 1b is resinified due to the shearing force generated in the punching process, and punched edges of the film 1a and the unwoven cloth 1b are welded together. If a separator 1 consisting of the film 1a integrated with the unwoven cloth is inserted in a battery during the process of assembling the battery, the film 1a can be prevented from making any positional shift from the unwoven cloth 1b. Thus, the life of charge/discharge cycle of the battery can be stabilized. |
