Yoshinori Matsuura

Hydrogen-absorbing alloy electrode for metal hydride alkaline batteries and process for producing the same

A hydrogen-absorbing alloy electrode for metal hydride alkaline batteries uses as hydrogen-absorbing material a powder of a rare earth element-nickel hydrogen-absorbing alloy obtained by pulverizing thin strips of said alloy prepared by single roll process and having an average thickness of 0.08 to 0.35 mm and a minimum size of crystal grains present in the roll-surface size of at least 0.2 μm and a maximum size of crystal grains in the open-surface side of not more than 20 μm. A process for producing the above electrode is also provided. The electrode can provide, when used as negative electrode, metal hydride alkaline batteries which are excellent in both high-rate discharge characteristics at an initial period of charge-discharge cycles and charge-discharge cycle characteristics.

Hydrogen-absorbing alloy electrode for metal hydride alkaline battery

A hydrogen-absorbing alloy electrode for metal hydride alkaline batteries is obtained by coating or filling a collector with a hydrogen-absorbing alloy powder consisting essentially of spherical particles and/or nearly spherical particles and then sintering the powder, the powder having an average particle diameter of 30 to 70 μm and containing 5 to 30% by volume of particles having a diameter of at least 2 times the average diameter and 10 to 40% by volume of particles having a diameter of not more than 1/2 of the average diameter. This electrode can give metal hydride alkaline batteries having excellent high-rate discharge characteristics and a long life.