Panasonic Corporation

Tsuneyoshi Murakami

Hiroyuki Usui

Takashi Okawa

Kenichi Aoki

Kimihiro Imamura

A nickel hydrogen storage battery is provided which includes an electrode assembly formed by winding spirally a strip-like negative electrode () and a strip-like positive electrode with a separator interposed therebetween, the strip-like negative electrode () having a mixture layer containing a hydrogen storage alloy disposed on a core material. The electrode assembly is contained in a bottomed cylindrical container such that the negative electrode () forms the outermost peripheral portion. A portion corresponding to an outermost peripheral portion () of the negative electrode is a thin portion, and the thin portion is bent in advance in the winding direction of the electrode assembly to form an arc shape. In this manner, when the spirally wound electrode assembly is configured, the outermost peripheral portion of the negative electrode is prevented from peeling from the electrode assembly, and thus the insertability into the bottomed cylindrical container is improved.

Nickel hydrogen storage battery and method for manufacturing negative electrode thereof

A nickel metal hydride rechargeable battery has a closed-end tubular container containing a spiral-shaped electrode assembly formed by winding a negative a positive electrode with a separator interposed therebetween such that the outermost periphery of the assembly is the negative electrode which is formed by disposing on a conductive substrate a mixture layer containing a hydrogen-absorption alloy. The positive electrode employs nickel hydroxide as an active material. In the nickel metal hydride rechargeable battery, the surface roughness of the outermost peripheral portion of the mixture layer of the negative electrode which contacts an inner side wall of the closed-end tubular container is 3.5 &#x3bc;M or more in terms of ten-point average roughness and is larger than the surface roughness of the other portion of the mixture layer. The reduction of oxygen gas during rapid charging is thereby facilitated without lowering the design capacity of the battery.

Growing community of inventors

Kanagawa, Japan

Tsuneyoshi Murakami