Abstract: The cycle lifes of Ni/MH battery at 1C rate charge-discharge and 1C rate charge 10C ratedischarge were tested. The results show that the cycle number in the latter case is only 76. The internal resistance, potential of positive,negative electrodes, performance of negative electrode of battery after76 cycles at 10C rate discharge and corrosion mechanism for hydrogen storage alloys were investigated.The results show higher temperature of Ni/MH battery at 10C rate discharge results in the corrosion rate of alloys increasing. Loss of water in electrolyte due to alloy corrosion. It leads to internal re-sistance increasing,negative electrode performance fading, and shorter cycle life of MH/Ni batteries.