Matsushita Electric Industrial Co., Ltd.

Takao Uyama

Susumu Yamanaka

Yasushi Hirakawa

Toshihiko Ikehata

Mitsugu Okahisa

Daisuke Yoshida

Tetsuya Takeuchi

Toshihiko Izumikawa

A coin-shaped battery includes a cathode case ( ) having a crimp portion ( ) in the periphery of a bottom face ( ), and an anode cap ( ) having a flange ( ) with an extended portion ( ) and a turn-up portion ( ). Openings of cathode case ( ) and the anode cap ( ) are sealed by crimping with a gasket ( ) interposed therebetween, so that the gasket ( ) is compressed between the crimp portion ( ) having a U-shaped cross section, the flange ( ), the extended portion ( ) and the turn-up portion ( ) to effect reliable sealing. Thus, it is possible to disperse a deformation pressure, which is generated by bulge of the cathode case ( ) and the anode cap ( ) caused with a rise in internal pressure of the battery under severe working conditions such as use under a high temperature. As a result, the coin-shaped battery having improved liquid leakage resistance in the crimped portion is provided.

Coin-shaped battery

The instant specification discloses a flat battery constituted by sealing a power generation element with: a case that works as one electrode terminal; a sealing plate that works as the other electrode terminal and has a flat central section projected outward and a flat peripheral section extending substantially parallel to the flat central section; and a gasket that insulates the case from the sealing plate, characterized in that the peripheral section of the sealing plate has an outer circumferential part being bent, or the case has a turned edge provided to make the peripheral section of the sealing plate fitted therein via the gasket and to partly press the gasket. The flat battery of the present invention having improvement in shape of the sealing plate and/or the case is sufficiently thin and exerts the effects of high leakage resistance and excellent mass productivity.

Flat battery

Growing community of inventors

Hirakata, Japan

Takao Uyama