摘要 |
A hydrogen storage alloy used in a hydrogen storage alloy electrode 11 has a crystalline structure having a mixed phase made up of at least an A2B7 type structure and an A5B19 type structure, and a surface layer of hydrogen storage alloy particles is so formed as to have a nickel content ratio greater than that of a bulk. The ratio (X/Y) of the nickel content ratio X (% by mass) of the surface layer to the nickel content ratio Y (% by mass) of the bulk is greater than 1.0 but no more than 1.2 (1.0<X/Y<=1.2). The gradient between the content ratio of the nickel in the surface layer of the hydrogen storage alloy particles and the content ratio of the nickel in the bulk is alleviated and a hydrogen storage alloy electrode with high output characteristics is obtained.
|