Sanyo Electric Co., Ltd.

Hideyuki Asanuma

Takashi Nagase

Masao Inoue

Takeo Hamamatsu

Yoshihiro Masuda

Satoru Kometani

Naoyoshi Hinotsu

Eiji Enishi

Toshiyuki Kondo

A battery including an outer casing, positive and negative electrodes provided in the outer casing, and an electrolyte provided therebetween. The outer casing is electrically connected to one of the positive and negative electrodes to constitute one of electrode terminals. The other is connected to the other electrode terminal which is electrically insulated from the outer casing. At least one of the positive and negative electrodes and the electrode terminal are connected to each other through a collector, which includes a plate-shaped body section and a connecting piece extended in an almost vertical direction from an end of the body section. The body section or the connecting piece is provided with a bending guide section which can be bent in such a direction that the connecting piece approaches the body section.

Collector used for an alkali storage battery

A rectangular alkaline storage battery includes an electrode plate which can be easily prepared and has a high packing density of active material and volumetric energy density. A connected negative electrode plate with hydrogen-absorbing alloy negative electrode plates is bent into a U-shaped form at a central portion (connecting portion). A composite positive electrode plate is then sandwiched by the hydrogen-absorbing alloy negative electrode plates with a separator made of an unwoven polypropylene fabric provided interposed therebetween to prepare an electrode plate unit. Two such electrode plate units are then laminated to form a group of electrode plates.

Rectangular battery

A sealed rectangular battery has a conductive battery case including an external casing and a sealing cap. The external casing encloses a generator element and is sealed by attaching the sealing cap using heat. The battery includes an electrode terminal with an opposite polarity to the battery case, and a safety valve. The safety valve includes a cap that is charged with the same polarity as the battery case and a valving element that covers a vent hole. The electrode terminal and safety valve are provided separately at different positions on the battery case. This construction is simpler than conventional batteries where the safety valve is integrally formed with an electrode terminal, which means that the electrode terminal can be miniaturized. This battery also has improved internal resistance.

Sealed rectangular battery and manufacturing method for the same

A battery structure is arranged such that an elastic valve body or the like cannot easily come off from the cover body during the production of the battery, which thereby enhances the production yield. A cover body of the invention includes a flange portion airtightly fixed to an injection port and a bulge portion protruding from the flange portion and provided with a space in which an elastic valve body is fitted (mounted). The bulge portion has an opening for ventilation provided on the side wall thereof and a protrusion at the lower end of the side wall thereof protruding inwardly of the side wall, whereby the elastic valve body can be held by the protrusion and the annular rim of the elastic valve body so that it can be prevented from coming off from the cover body. Accordingly, the elastic valve body can be prevented from coming off from the cover body due to vibration developed during the transportation of the cover body or like occasions, making it possible to enhance the production yield.

Growing community of inventors

Matsushige, Japan

Hideyuki Asanuma