Performance of Al-Air Batteries Based on Al–Ga, Al–In and Al–Sn Alloy Electrodes

In this paper, the performance of Al-air batteries based on pure Al, Al–0.1 wt%Ga, Al–0.1 wt%In and Al–0.1 wt%Sn anodes in 1 M KOH solutions was investigated by galvanostatic discharge test. The electrochemical characteristics of the anodes were investigated by means of hydrogen collection, tafel polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM). The results reveal that compared with pure Al in 1 M KOH, Al–0.1 wt%In or Al–0.1 wt%Sn exhibits a lower self-corrosion rate and higher electrochemical activity because indium or tin with a high hydrogen evolution overpotential deposits on the aluminum surface. The Al–0.1 wt%Ga alloy is not an ideal anode of alkaline Al-air battery because the severe self-corrosion. The results of galvanostatic discharge at a current density from 1 to 40 mA cm −2 indicate that the Al-air batteries based on both Al–0.1 wt%In and Al–0.1 wt%Sn anodes in 1 M KOH show excellent discharge performance and high anodic efficiencies.