| Aluminum has high energy density, good power density and high abundance in the earth's crust which make it a favourable candidate fuel in metal-air batteries. Aluminum and aluminum alloys have two defects as anode material. Aluminum has a very large affinity for oxygen and hence increase the over-potential to decrease the potential efficiency, that means decrease the output power; whatmore, in the alkaline and corrosion medias, aluminum dissolves very fast and produce volume hydrogen, which decrease the Faraday efficiency. In order to improve the property of aluminum, zincum,indium,stannum, magnesium, bismuth,RE, gallium were chosed to add in Aluminum, and cast a series of Aluminum alloys.The open-potential,work-potential,anode efficiency,self-corrosion rate, electrochemistry property were measured. The microstructure was observed by EMPA, and the effect of homogeneous to aluminum alloys and microstructure was discussed. The surface of aluminum alloys were analysed after work 60min in 4mol·L-1 KOH solution by EDAX. The active mechanism of aluminum alloys anodes were explained. The results showed (1)In series of Al-Zn-X(X=RE,In,Bi,Ga)alloys, the comprehensive property of alloy anodes which contained RE was better than others. The open-potential and work-potential of Al-1Mg-0.1Ga alloy were higher than Al-1Mg-0.05Ga alloy, but it had higher self-corrosion rate. The open-potential increased after adding RE to Al-Zn-In-Sn-Mg, but the work-potential decreased. The current efficiency of aluminum anodes by water-quenching decreased,and the potential changed more negative. (2)The segregation containing Fe existed in Al-Mg-Ga alloy. Two kinds of segregation containing Fe and containing Zn were detected in Al-Zn-In-Sn-Mg. Two kinds of segregation containing Fe and containing RE were detected in Al-Zn-In-Sn-Mg-RE. The active elements such as Zn,Sn,Mg were detected in the segregation of RE. (3)The corrosion product of aluminum anodes were oxide or hydroxide of Al,Zn,In. Fe,Si were measured in grain boundary corrosion product. The corrosion pits dispersed evenly. Indium was measured in corrosion product in alloy anodes had been water-guenched. (4)The corrosion degree of grain was faster than grain boundary. Indium in α-Al dissolved first, increased the active pits, and then active the Al alloys. Indium proved that the active mechanism also follow dissolve-redeposit mechanism. when add different elements ,the alloys had different electrochemistry impedance. The alloy which contained RE had the lowest electrochemistry impedance and highest activity.
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