Matsushita Electric Industrial Co., Ltd.

Seiichi Mizutani

Fumio Daio

Hideaki Yoshio

Kenjin Masumoto

Shinji Tsurutani

Hideyuki Kobayashi

Saburo Nakatsuka

Yoshinori Iwaizono

Katsuhiko Mori

Mitsugu Okahisa

Mamoru Iida

Tomiya Ishimaru

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.

Closure assembly for sealed batteries

A protective circuit having an electronic circuit constructed on a circuit board is built into a sealing member that seals the open end of a battery case accommodating electricity generating elements. The circuit board is attached to the outer end of the sealing member. A positive terminal plate that becomes the positive terminal of the secondary battery and an S pole terminal plate that controls the operation of the electronic circuit by an external connection are provided on the outer surface of the circuit board. Thereby, a protective circuit that prevents over-discharging and overcharging is arranged inside the sealing member. A secondary battery is thereby constructed with a protective circuit without resorting to a construction of a battery pack.

Secondary battery

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.

Sealed battery and method for manufacturing same

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.

In a cell assembly, a cell has terminal elements for attachment to mating terminal elements. Each of the terminal elements has an engaging portion with peripheral ends bent to form an interior region and an first surface with an opening and a projection projecting partially into the interior region from a second surface. The material used has a wall thickness in the range of 0.15-10 mm, a Vickers hardness of 250-450 HV and a spring limit value of 30-60 kgf/mm.sup.2. Alternatively, a circuit substrate is provided with such engaging portions.

Cell with terminals and circuit substrate

Socket terminal

Battery with terminal

Battery for an IC card

Growing community of inventors

Hirakata, Japan

Seiichi Mizutani