Investigation of Sodium Phosphate and Sodium Dodecylbenzenesulfonate as Electrolyte Additives for AZ91 Magnesium-Air Battery

Abstract

This paper reports on the improvement of discharge performances of magnesium-air batteries by adding sodium phosphate and sodium dodecylbenzenesulfonate to sodium chloride aqueous solution. Four different electrolytes are tested. Results obtained show that the discharge potential and anode utilization of magnesium-air battery increase significantly with addition of the additives. With an electrolyte of 3.5 wt% sodium chloride+0.5 g·L−1 sodium phosphate, the discharge potential increases from 1.120 V to 1.150 V and the anode utilization increases from 44.1% to 49.1%. The self-corrosion rate of anode has a tendency to decrease with addition of the additives. In solution of 3.5 wt% sodium chloride+0.5 g·L−1 sodium dodecylbenzenesulfonate +0.5g·L−1 sodium phosphate, the self-corrosion is low and the inhibition efficiency can reach 95.2%.