A nickel-zinc galvanic cell is provided, having a zinc oxide negative electrode, a nickel oxide positive electrode, and an alkaline electrolyte. Chemical additives are placed in each of the negative and positive electrodes. The positive nickel hydroxide electrode contains a mixture of cobalt oxide contained within a nickel oxide matrix in the range of about 1% to 10%, and cobalt metal in the range of about 1% to 10%, by weight. The negative zinc oxide electrode may contain oxides other than the oxide of zinc, which have redox potentials which are negative of −0.73 volts. Also, the metal oxide additives to the negative zinc oxide electrode are such as to inhibit release of soluble cobalt from the nickel oxide negative electrode prior to a formation charge being applied to the electrochemical cell.