| 摘要 |
PURPOSE:To decrease the number of filling cycles by limiting impregnating condition in cadmium nitrate solution and electrolyzing condition in sodium hydroxide solution to a specified range. CONSTITUTION:A porous nickel substrate is immersed in cadmium nitrate solution to impregnate cadmium nitrate into the substrate, then the substrate is cathodically electrolyzed to form metallic cadmium. In this process, specific gravity of cadmium nitrate is specified to 2.0-2.4, and cathodic electrolysis of the substrate in sodium hydroxide solution is performed at a current density of 50-80mA/cm<2> for 30min or more. This process is defined as one filling cycle, and plots of filling density of Cd(OH)2 to filling cycles are shown in the curve E in the figure. The curve shows that the desired filling density of 1.9g/cm<3> is obtained by three filling cycles. The curve F by conventional method shows to require eight filling cycles to obtain the desired filling density. The curve G shows that pores are blocked at three filling cycles and filling is stopped. |
