Panasonic Corporation

Ichiro Matsuhisa

Yasushi Sumihiro

Susumu Kato

Seiji Wada

Yasuhiko Shoji

Yasuhiko Syoji

A gasket is made of an injection molded resin integral with a cylindrical boss portion having a through hole in which a current collector is inserted, a rim portion for sealing an opening of a battery case, and a connecting portion for connecting the boss portion and the rim portion, wherein the boss portion has an annular injection portion at an end face thereof, which is a trace of an injection molding gate, a ratio (S/S) between an axial cross-sectional area (S) of the boss portion and an axial cross-sectional area (S) of the injection portion is in the range of 10 to 25, and an outer diameter of the boss portion is in the range of 3.0 to 4.2 mm.

Battery gasket and alkaline battery using the same

A highly reliable cylindrical primary battery is provided where the surface temperature of a body portion of which at the time of a short circuit is controlled to be low. The heat conductivity &#x3bb; (W/m&#xb7;K) of a resin sealing body of a sealing assembly having a PTC element and the amount of heat generation Q (W) in the PTC element at the time of tripping are set so that the relational expressions of:0.12&#x2266;&#x3bb;&#x2266;0.27;&#x2003;&#x2003;(1)1.0&#x2266;Q&#x2266;1.5; and&#x2003;&#x2003;(2)&#x2266;&#x2212;3.33&#x3bb;+1.9 are met.&#x2003;&#x2003;(3)

Battery having positive temperature coefficient element

An alkaline battery according to the present invention includes: a battery case that houses a power generation element therein; and an assembly sealing portion that closes an opening of the battery case. The assembly sealing portion includes a negative terminal portion, a negative current collector electrically connected to the negative terminal portion, and a resin sealing body. The negative terminal portion includes a first negative terminal plate and a second negative terminal plate spaced apart from each other, and a PTC element placed between the first negative terminal plate and the second negative terminal plate.

Alkaline battery

A leak-proof alkaline dry battery including a battery case and a seal unit for closing the opening of the battery case. The seal unit includes: a negative electrode terminal plate; a negative electrode current collector nail electrically connected to the terminal plate; and a resin seal member. The resin seal member includes: a central cylindrical part having an opening through which the body of the negative electrode current collector nail is inserted; an outer peripheral cylindrical part interposed between a peripheral edge of the negative electrode terminal plate and an open edge of the battery case; a connecting part interconnecting the central and outer peripheral cylindrical parts; and a thinned section formed in the connecting part. The body of the negative electrode current collector nail is fitted to the opening of the central cylindrical part in a particular fit relation to prevent leakage for a long time.

Growing community of inventors

Hyogo, Japan

Ichiro Matsuhisa