Indium chloride as an electrolyte additive for primary aqueous Mg batteries

Abstract Indium chloride (InCl3) as an electrolyte additive for primary aqueous Mg batteries is evaluated in this work in terms of its effect on discharge potential, self-corrosion rate and utilization efficiency of a newly developed Mg-0.15Ca anode. InCl3 addition to aqueous electrolyte leads to a more negative discharge potential but the enhancement weakens along with the consumption of In3+ to form In(OH)3 precipitates during the discharge process. Utilization efficiency of the anode is increased by adding InCl3 due to uniform anodic dissolution and suppressed self-corrosion with reduced chunk effect. Mg-air battery test results indicate that 10 mM InCl3 as electrolyte additive significantly enhances the cell voltage of aqueous Mg-air battery to 1.74 V and the specific energy based on anode weight loss to 2.26 kWh/ kg at 1 mA cm−2.