ARUKARICHIKUDENCHOPEESUTOSHIKIKADOMIUMUFUKYOKUNOSEIZOHO

摘要

PURPOSE:To retard the growth of cadmium hydroxide in a nickel layer and to increase the life by adding cadmium ions in a nickel plating bath. CONSTITUTION:A cadmium active material-coated plate is cathodically electrolyzed in a nickel solution containing cadmium ions to form a mixed thin layer of nickel and cadmium on the surface of the plate. The plate is impregnated with a magnesium salt solution and the magnesium salt is converted into magnesium hydroxide to form the magnesium hydroxide in the mixed layer of nickel and cadmium formed in the active material layer or on the surface of the plate. By conducting electroplating on the surface of the electrode in a mixed solution containing 0.05-0.2mole/l nickel salt and 10<-4>-10<-2>mole/l cadmium salt at a current density of 50-200mA/cm<2>, a dense metallic nickel layer containing fine metallic cadmium particles is formed on the surface of the electrode. The dissolution and diffusion of discharge products in a high temperature region is prevented and charge-discharge cycles are increased.