Study on the Electrolyte Containing AlBr3 and KBr for Rechargeable Aluminum Batteries

Abstract

The reversible redox reaction of Al 3+ /Al or Al deposition/dissolution was investigated in ethylbenzene containing AlBr 3 and KBr as an electrolytic solution for rechargeable aluminum batteries. KBr as a supporting electrolyte was also necessary for the reversible Al deposition/dissolution. This reversible redox reaction was observed on both glassy carbon (GC) and Pt electrodes. However, the charge/discharge tests showed that the GC and Pt electrodes had different ratios of discharge capacity to charge capacity and current density for the Al deposition. A scanning electron micrograph of deposited metallic Al showed it had a rounded shape, suggesting that the growth of dangerous dendritic Al was efficiently inhibited in the present electrolyte solution.