Abstract: A battery manufacturing method including accommodating elements for electromotive force in a battery case having an oval cross section, placing a sealing member on an open end of the battery case with a gasket interposed therebetween, and sealing the battery by inwardly crimping the open end of the battery case. In the sealing step, long side edges of the battery case are crimped by a forming surface having a rounded cross section, and arc-shaped edges connecting both long side edges are crimped by a flat forming surface. A battery having excellent safety properties with no risk of liquid leakage due to its uniform, airtight, and highly reliable seal around the entire circumference of the open end of the battery case is thus provided.

Abstract: A closure assembly for sealed batteries in which explosion-proof features are incorporated. A metal plate having a hole, an insulating resin sheet, a metal thin sheet, an insulating sheet having an air hole, a metal guide plate having a hole, and a metal cap are laid upon one another within an insulating gasket. Metal plate and metal guide plate are in contact with each other and electrically connected. Upon a build-up of pressure within the battery, the insulating resin sheet expands and ruptures, whereby a narrow part provided in the metal thin sheet positioned above the insulating resin sheet breaks, thus cutting supply of electric current.

Abstract: A metal reinforcing plate is welded in place close to the opening on the inside of the battery case, and a plastic insulation gasket and a sealing member provided with an anti-explosion mechanism or the like are sequentially mounted on the metal reinforcing plate. By this arrangement, higher battery capacity can be realized by eliminating the waste of space because it is unnecessary to form a conventional indentation around the upper wall of a battery case. A sealed battery construction having an anti-explosion mechanism and being highly reliable in terms of leakage prevention can be thereby obtained.

Abstract: A secondary battery which may be handled in a same way as conventional single cell, if the gas pressure within battery went unusually high the gas is immediately discharged outside, and bursting of the battery is prevented.

Abstract: A closure assembly for sealed batteries in which explosion-proof features are incorporated. A metal plate (8) having a hole (81), an insulating resin sheet (9), a metal thin sheet (6b), an insulating sheet (4) having an air hole (41), a metal guide plate (3) having a hole (31), and a metal cap (1b) are laid upon one another within an insulating gasket (5b). Metal plate (8) and metal guide plate (3) are in contact with each other and electrically connected. Upon a build-up of pressure within the battery, the insulating resin sheet (9) expands and ruptures, whereby a narrow part (69) provided in the metal thin sheet (6b) positioned above the insulating resin sheet (9) breaks, thus cutting supply of electric current.

Abstract: A closure assembly for sealed batteries in which explosion-proof features are incorporated. A metal plate (8) having a hole (81), an insulating resin sheet (9), a metal thin sheet (6b), an insulating sheet (4) having an air hole (41), a metal guide plate (3) having a hole (31), and a metal cap (1b) are laid upon one another within an insulating gasket (5b). Metal plate (8) and metal guide plate (3) are in contact with each other and electrically connected. Upon a build-up of pressure within the battery, the insulating-resin sheet (9) expands and ruptures, whereby a narrow part (69) provided in the metal thin sheet (6b) positioned above the insulating resin sheet (9) breaks, thus cutting supply of electric current.

Abstract: A method for producing a sealing member for a battery includes integrally insert-molding a gasket on a peripheral edge of a metal sealing plate. The gasket is molded on the peripheral edge of the metal sealing plate by inserting the metal sealing plate between the female and male molds, the female mold having a concave surface conforming to the upper surface of the metal sealing plate and provided with a magnet or vacuum suction mouth to attract the metal sealing plate in its center, and the male mold having a surface conforming to the lower surface of the metal sealing plate, then injecting a molten resin into a cavity formed between the female mold and the male mold while pressing the female and male molds against each other by an elastic member.