LaNi5-based alloys were paid more attention due to their high capacity,high charge/discharge ability,ease of activation and low hydriding/dehydriding pressure.The electrochemical capacity of commercial AB5-type materials has reached 320-340 mAh/g at 0.2-0.3 C rate.It seems to be difficult to further improve the capacity of the AB5-type alloys since the theoretical capacity of LaNi5 is about 372 mAh/g.Surface treatment is found to be an effective way of improving the overall capability.The surface modification of hydrogen storage alloys by milling the parent alloy with an additional element such as pure metals,metalloid,metal oxides and metal disulfide can effectively reduces the rate of degradation of the electrode upon consecutive cycling.Adding the 3d transition metal oxides into alloy electrodes to improve the electrochemical properties was a low production cost method.