Electrochemical behaviour and discharge characteristics of an Al–Zn–In–Sn anode for Al-air batteries in an alkaline electrolyte

Abstract

Abstract The electrochemical behaviour and discharge characteristics of Al-4.5Zn-0.05In (wt.%), Al-4.5Zn-0.05Sn (wt.%) and Al-4.5Zn-0.05In-0.05Sn (wt.%) anodes for Al-air batteries in 4 M NaOH solutions are investigated through electrochemical methods, full-cell tests, and microstructure observations. Adding Sn to the Al-4.5Zn-0.05In (wt.%) anode improves its discharge performance. Sn ions, like In ions, can be repeatedly adsorbed and desorbed onto the anode surface, resulting in the attenuation of the passivation layer. The Al-4.5Zn-0.05In-0.05Sn (wt.%) anode exhibits better discharge characteristics than the Al-4.5Zn-0.05In (wt.%) and Al-4.5Zn-0.05Sn (wt.%) anodes, especially at large current densities. Furthermore, the peak energy density of the Al-4.5Zn-0.05In-0.05Sn (wt.%) anode can reach approximately 3628.64 Wh kg−1, which is 11.80% and 14.21% higher than that of Al-4.5Zn-0.05In (wt.%) and Al-4.5Zn-0.05Sn (wt.%) anodes, respectively.