Matsushita Electric Industrial Co., Ltd.

Mitsui Minings & Melting Co., Ltd.

Ryohei Ashihara

Kikumitsu Suehiro

Koichi Sato

Kohei Kubota

Hajime Murakami

Keiji Ogino

Jun Miyoshi

Kazuo Sugino

Akira Kato

Susumu Kato

Seiji Wada

Yasushi Sumihiro

Yuji Mototani

Isao Kubo

Michiko Inui

Koji Inokuchi

Tetsuya Kobayashi

Masayuki Yabuta

Hideaki Yamagishi

Masatsugu Eri

Shohei Nozaki

Eiji Tano

A manganese dry battery with excellent leak-proof property is provided, in which electrolyte leakage does not occur even if the size of a positive electrode material mixture is increased to meet a demand for improvement in discharge property. In a sealing part, a first circular projection, a second circular projection and a third circular projection are arranged at the bottom in sequence from the center to the outside, and a positive electrode carbon rod supporting part is provided in an innermost periphery portion to have an interval from the first circular projection. A groove between the first projection and the carbon rod is formed to have a substantially rectangular vertical section, kraft board is pressed by flat bottom surfaces of the first and second projections and an opening of the zinc can is fitted between the second and third projections.

Manganese dry battery

In order to enable the safer use of an assembly of multiple cells comprising: a plurality of unit cells; an outer container for housing the unit cells; a terminal plate for sealing an upper opening of the outer container; and a positive output terminal and a negative output terminal formed on the same face of the terminal plate, at least the side face of the negative output terminal is covered by a protective tube having an electrical insulation property.

Battery

There is described in the specification a mercury-free manganese primary dry battery wherein the cathode mixture contains boric acid or an alkali borate at a ratio of 0.04 to 0.4 parts by weight per 100 parts by weight of manganese dioxide as a boron conversion value or wherein the separator contains boric acid or an alkali borate at a ratio of 0.1 to 8.0 parts by weight per 100 parts by weight of a dry solid content in the pasting agent. Such battery has excellent discharge properties under light loading conditions.

Manganese dry batteries

The present invention provides a method of manufacturing a zinc-titanium mother alloy and a manganese dry battery having an anode zinc can prepared from the zinc-titanium alloy. The method comprises: adding spongy titanium to molten zinc; and melting the spongy titanium to alloy with the zinc at 500.degree. to 750.degree. C. for 0.5 to 6 hours, thereby to obtain a zinc-titanium alloy which contains 0.001 to 5% by weight of titanium. The anode zinc can prepared from the zinc-titanium mother alloy is substantially free from metallic titanium and intermetallic compounds having the Zn--Ti atomic ratio of not less than 1/2.

Method of manufacturing zinc-titanium mother alloy and manganese dry

A manganese dry battery includes an anode zinc can made of a zinc alloy containing 0.001-0.5 wt. % of titanium and at least one element selected from the group consisting of 0.001-0.05 wt. % of indium and 0.001-0.05 wt. % of bismuth, or a zinc alloy further containing 0.01-0.4 wt. % of lead. Even without heavy metals such as Hg and Cd, the zinc alloy anode can has a corrosion-resistant property and mechanical strength equivalent to or greater than those of the conventional zinc anode can, thereby giving a low pollution zinc-carbon battery having a storage characteristic equivalent or superior to that of the conventional zinc anode can.

A dry cell comprising an anode made of zinc and cathode mixture which includes manganese dioxide acting as active agent and conductor such that acetylene black having a specific surface area of 100 to 150 m.sup.2 /g measured by a BET type nitrogen gas adsorption method is used as the conductor by setting a mixing ratio in weight of the manganese dioxide to the acetylene black at 7/1 to 12/1.

Dry cell

An outer metal jacket for a dry cell, prepared by butting a rectangular metal plate at both side edges and joining the butted part by welding or bonding to make a cylindrical body, characterized in that a part having smaller mechanical strength is integrally provided on at least one of the upper and lower rims of the cylindrical body as a safety mechanism. When the inner pressure is increased by any reason originated from an electrochemical cell system accommodated therein, the safety mechanism is opened outwardly and the increased pressure is reduced therethrough.

Metal jacket and dry cell using the same

A dry cell which is so arranged that, with a bottom plate being disposed at the lower portion of a raw cell sealed at its opening by a sealing member, an insulative seal packing is applied onto the peripheral portion of the bottom plate, while the raw cell and the peripheral portion of the bottom plate are surrounded by a metal jacket welded by laser at its butted opposite ends. At the peripheral portion of the bottom plate, a gas discharge mechanism is formed which is arranged to be normally closed by the seal packing, and to be released from the closing by the seal packing due to deformation of the bottom plate upon increase of internal pressure of the dry cell for discharging the gas within the dry cell outside, and thus, a safe dry cell free from a danger of rupture maybe provided.

Growing community of inventors

Neyagawa, Japan

Ryohei Ashihara