Matsushita Electric Industrial Co., Ltd.

Ikkoseiko Co., Ltd.

Susumu Kitaoka

Katsuhiko Mori

Akira Iwase

Isao Matsumoto

Yoshio Moriwaki

Tadahiro Tokumoto

Shoji Yamashita

Tomomichi Ueda

Masatoshi Hano

Mamoru Iida

Kazuyuki Higashi

Shigekazu Tanaka

Hisashi Komeno

Tokiya Fujimoto

Yoshio Gohda

A prismatic battery case with high dimensional precision is manufactured, while pursuing an improvement in productivity, with a manufacturing method of a prismatic battery case that includes a first step for molding an intermediate cup body () by impact molding a pellet () of prescribed shape, and a second step for molding a prismatic battery case () with a cross section of substantially rectangular shape by DI processing the intermediate cup body (). The DI processing conducts drawing and ironing continuously, in one action.

Square battery container, method of manufacturing the container, and square battery using the container

A prismatic battery case () has a configuration wherein a rectangular shorter-side plate () has a thickness (A) larger than a thickness (B) of a longer-side plate (). When the prismatic battery case () is manufactured, a battery case material () punched into a predetermined shape undergoes deep drawing to form a first intermediate cup element () having a substantially elliptic cross section; the first intermediate cup element () undergoes redrawing successively in a plural stages to form a second intermediate cup element () having a substantially elliptic cross section which is smaller in minor-axis-diameter to major-axis-diameter ratio; and the second intermediate cup element () undergoes DI processing to form the prismatic battery case () having a substantially rectangular cross section wherein the thickness (A) of the shorter-side plate () is made larger than the thickness (B) of the longer-side plate ().

Square cell container and method of manufacturing the cell container

A battery has elements for electromotive-force accommodated in a metal outer can which has a bottom having a cylindrical, prismatic or similar shape. The ratio of the bottom thickness (TA) the side thickness (TB) is 1.5-7.0. The metal outer can contains primarily iron and a layer of nickel is provided on at least the inner face of the battery. Shallow grooves are formed on the nickel layer perpendicular to the bottom face. An iron-based metallic sheet formed with a nickel layer on at least one face is subjected to drawing forming into a tubular shape having a bottom, continuous ironing processing being performed such that the side of the can formed in the tubular shape has an ironing ratio in the range of 20% to 90% and a metal outer can is thereby manufactured having a ratio of a bottom thickness to its side thickness from 1.5 to 7.0, having a cylindrical shape, prismatic shape or shape similar thereto, and with shallow longitudinal grooves formed in a nickel layer provided on the battery inside face.

Metal outer can for a battery and method of manufacturing same

A battery accommodates elements for electromotive-force within a metal case. This metal case is a metal case having a bottom wherein the bottom thickness/side thickness ratio has a value of 1.2-4.0 and has a cylindrical, prismatic or similar shape. The metal case is constructed of a metal material whose chief constituent is aluminum. Furthermore, it is desirable that a multiplicity of shallow grooves perpendicular to a bottom face are formed in at least a battery inside face of the metal case and moreover that a nickel layer is provided on the battery inside face. The metal case is made by DI processing involving drawing and ironing, to have a value of bottom thickness/side thickness ratio which was hitherto unavailable,i.e., 1.2-4.0 can be obtained.

Battery and method of manufacturing therefor

This invention relates to a method to manufacture cell-cans by DI can method, by manufacturing a bottomed cylindrical cup-shaped intermediate product from a sheet material of which both surfaces are nickel plated and annealed in an atmosphere of inert gas making the metal nickel layer thickness and the hardness at predetermined values, then ironing the intermediate product at a predetermined ironing rate, securing a thickness of the metal nickel layer of more than 1.0 .mu.m and a Vickers hardness of more than HV 200 on the side wall of finished cell-cans. By this, conventional defect problems due to the cracks generated on the intermediate product can be solved completely and the problem of hair-lines formed on the surface of finished cell-can can be eliminated.

Method to manufacture cell-cans

Growing community of inventors

Hirakata, Japan

Susumu Kitaoka