An oxidation-resistant carbon and ethylene-vinyl-acetate were dispersed in xylene as the solvent. The prepared carbon dispersion was sprayed onto spherical Ni(OH)2 particles using a fluid-bed coating apparatus (Powrex Co., Ltd., Japan) to obtain the carbon-coated Ni(OH)2 powder as the positive electrode material. The carbon-coated Ni(OH)2 was formed into the positive electrode in the same manner as the negative electrode, namely, a paste consisting of the carbon-coated Ni(OH)2 powder and CMC with water was loaded on a nickel foam substrate and pressed to form a plate with a thickness of 0.4 mm.