Matsushita Electric Industrial Co., Ltd.

Yoji Kajikawa

Junichi Asaoka

Jun Miyoshi

Isao Kubo

Toshikazu Kaneko

Hirofumi Iwaki

Akira Ota

Yoshio Kino

The present invention provides a cylindrical alkaline battery comprising a positive electrode case of a cylindrical form having an opening at one end and accommodating an electricity-generating element comprising a positive electrode, a negative electrode, a separator and an alkaline electrolytic solution, an insulating gasket provided at the opening of the positive electrode case, a bottom plate being the negative electrode terminal provided on the gasket, and a heat-shrinkable member such as shrink tube or the like covering the outer surface of the positive electrode case. In this battery, the opening end of the positive electrode case and the outer surface of the battery extending therefrom are covered with an electrical insulating film. The presence of the electrical insulating film prevents the exterior short circuit between the positive electrode case and the bottom plate being the negative electrode terminal which may occur when the metal material of the case opening is exposed by the peeling or abnormal shrinkage of the heat-shrinkable member. The present invention also provides a cylindrical alkaline battery comprising a reinforcing washer provided between the bottom plate being the negative electrode terminal and the gasket. In this battery, electric insulation is established between the bottom plate being the negative electrode terminal and the washer or between the gasket and the washer and the presence or the electric insulation cuts off the possible electric reaction route forming a local cell and prevents the resultant leakage of the electrolytic solution.

Cylindrical alkaline batteries

A dry cell of the type enclosing therein an electrolyte mainly consisting of zinc chloride, wherein in order to ensure the more secure air- and liquid-tightness a filler or sealing agent is filled into the space between a plastic top seal and a metal top seal to seal a carbon electrode extended out of the plastic top and the upper end portion of a plastic tube covering the top surface of the plastic top seal, whereby the longer shelf life may be ensured.

Dry cell

Growing community of inventors

Katano, Japan

Yoji Kajikawa