PURPOSE: To prevent any deterioration of the active material of a cadmium electrode for a sealed nickel-cadmium secondary electrode for a sealed nickel- cadmium secondary battery by completely removing a solvent so as to inhibit the oxidation of metallic cadmium by packing a slurry-like active material before it is dried in an inactive gas.

CONSTITUTION: Mixture powder consisting of cadmium oxide and metallic cadmium is kneaded with ethylene glycol to make a slurry. The slurry is then packed into a nickel fiber sintered body or a nickel-plated iron fiber sintered body. After that, the thus obtained body is treated in an atmosphere of an inactive gas such as argon or nitrogen at a temperature lower than the melting point of metallic cadmium to remove ethylene glycol. In the plate according to this invention, the amount of metallic cadmium remaining in its active material is 90∼95% of the amount of metallic cadmium blended in preparing a paste. Besides, drying treatment can be carried out at a high temperature below the melting point of cadmium, thereby enabling ethylene glycol to be removed in a short time.