A Review of Al Alloy Anodes for Al–Air Batteries in Neutral and Alkaline Aqueous Electrolytes

Aluminum–air (Al–air) batteries are promising candidates for energy storage applications because of their high theoretical energy density and low cost. Nevertheless, their developments have been severely hindered by multiple obstacles, among which the activation and self-corrosion inhibition of Al anode have been considered to be significant challenges. In neutral electrolytes, the main problem is the activation of Al anode, while the self-corrosion of Al anode becomes dominant in alkaline electrolytes. Considerable efforts have been devoted to overcoming the dilemma associated with the Al anode. This review firstly underscores the underlying mechanisms of passivation and self-corrosion of Al anode in different electrolytes. Then, specific attentions are paid to Al alloy anode, including the role of various elements and standard processing technology. Finally, general conclusions, current limitations, and future perspectives on Al alloy anode are presented.