Organic/inorganic double solutions for magnesium–air batteries

Abstract

In order to limit the anode corrosion and improve the battery activity, magnesium–air batteries with organic/inorganic double solutions (0.5 M Mg(ClO₄)₂–N,N-dimethylformamide (DMF)/0.6 M NaCl–H₂O, 0.5 M Mg(ClO₄)₂–acetonitrile (AN)/0.6 M NaCl–H₂O) were prepared. The discharge performance, discharge morphology, and corrosion performance of magnesium anode were researched. Results obtained show that organic electrolytes separate the anode from the aqueous electrolyte, thus improving the anode utilization rate. Due to the NaCl electrolyte used in the air cathode side, batteries show higher discharge voltages. As an example, a better discharge performance has been observed in Mg(ClO₄)₂–DMF/NaCl–H₂O double electrolytes at 1 mA cm⁻² discharge. This is attributed to there being no obvious absorption of corrosion products on the anode surface. The results of the discharge morphology and electrochemical impedance spectroscopy agree well with the discharge performance. The magnesium anode discharge mechanism is different for different solutions.