PURPOSE: To retain the high sealability of a sealing part and to ensure safety when an accident arises by using a resin gasket as a sealing member, and melt bonding the gasket with a metal cover by injection molding using a mold.
CONSTITUTION: A hole 21 having cut-off part 20 is formed in the center of a metal cover 2 which also serves as a positive terminal. A negative terminal 5 is fixed to the metal cover 2 via a resin gasket to form the sealing part of a battery. The resin is selected from polyimide 11, polyamide 12, miodified polypropylene, and modified polyethylene. The resin is filled into a space 17 formed by supporting the cover 2 with an upper mold 15 and a lower mold 16, and the resin gasket is melt bonded to the cover 2. The battery is usually sealed by the gasket. When the inner pressure of the battery is accidentally increased, the resin gasket is broken by the help of the cut-off part 20 and inner gas is released from the battery.
NAGAO NOBUHIRO
AMEZUTSUMI TORU
URUSHIBARA KANJI
