Evaluating the Discharge Performance of Heat-Treated Al-Sb Alloys for Al-Air Batteries

In this work, the combined effects of heat treatment and Sb addition on the discharge performance of Al-Sb alloys as anode for Al-air batteries have been evaluated experimentally. The results indicate that heat treatment decreases the electrochemical and discharge activities of Al-Sb alloys. Heat-treated Al-Sb alloys at 550 °C for 3 h show an improved anode performance. The Al-0.02Sb alloy exhibits a high discharge capacity and anodic efficiency of 2758 Ah kg−1 and 92.6%, respectively. Further prolonging the heat treatment time results in a decrease in anode performance. Microstructure characterization indicates that such negative effect is due to the higher-temperature and prolonged heat treatment to bring out significant grain growth and coarsening of Al-Sb precipitates. The corresponding corrosion behaviors are also discussed in detail.