The electrocatalysis of charge/discharge reactions of alkaline-iron electrodes with and without the Bi2S3 additive have been studied using cyclic voltammetry at different sweep rates and temperatures. The activation energy barriers for the iron-dissolution reaction on the iron electrodes with and without the sulfide additive are found to be 11.5 and 35.5 kJ mol(-1), respectively, suggesting that the presence of sulfide additive in iron-active material lowers the activation barrier for the iron dissolution reaction appreciably.