Abstract: A hydrogen absorbing electrode using a hydrogen absorbing alloy including at least one or more kinds of transition metals belonging to VIIb-group, VIII-group or Ib-group in periodic table at a specified percentage, characterized in that a surface part of the hydrogen absorbing alloy forms a rich layer including the foregoing transition metals at a percentage larger than the foregoing specified percentage. Since the rich layer exists, an activation at initial stage of charge/discharge is not required. Accordingly, this electrode can be utilized effectively for a nickel-hydride secondary battery.

Abstract: A separator for alkali-zinc battery comprising a microporous membrane having alkali resistance, a part of the porous membrane having highly persistent hydrophillic property and the remaining part having water repellent property. In the part having hydrophillic property, precipitation of ZnO can be controlled sufficiently because of its large persistency of hydrophilic property so that dendrite short-circuiting in the battery can be prevented satisfactorily. In the part having water repellent property, O.sub.2 gas is permeable well through it so that a decrease in capacity of battery can be avoided.

Abstract: A method for forming a nickel plate or a method for making up an alkaline battery, in such a way that cobalt oxyhydroxide is previously formed on surfaces of positive active material powder and used therefor, by mixing the positive active material powder with CoO powder, for example, to be oxidized, by oxidizing the positive active material powder in a solution including cobalt ions, or by mixing the positive active material powder with cobalt oxyhydroxide powder. A conductive network comprising the cobalt oxyhydroxide is formed, so that conductive efficiencies between the positive active materials and the positive active material and the substrate are made better.

Abstract: A separator for alkali-zinc battery comprising a microporous membrane having alkali resistance, a part of the porous membrane having highly persistent hydrophillic property and the remaining part having water repellent property. In the part having hydrophillic property, precipitation of ZnO can be controlled sufficiently because of its large persistency of hydrophilic property so that dendrite short-circuiting in the battery can be prevented satisfactorily. In the part having water repellent property, O.sub.2 gas is permeable well through it so that a decrease in capacity of battery can be avoided.