Effects of Sn on the electrochemistry and discharge performances of as-extruded Mg-1.2Ga as an anode for Mg-air batteries

Abstract

The effects of Sn in as-extruded Mg-1.2Ga alloys on the electrochemical and discharge properties were investigated by in-situ electrochemistry, half-cell and air-cell tests to provide new ideas for the development of magnesium alloy anode materials. The addition of Sn promoted grain refinement and deformation precipitation on the extrusion streamlines. Extrusion can effectively reduce the |bc| value of the alloy, improving the cathodic hydrogen control process. After the addition of Sn, more secondary phases are introduced. The redeposition and dissolution of Sn and Ga are enhanced. In conclusion, the GT12 alloy has excellent anode efficiency and average cell voltage, and its maximum discharge capacity (1292.98 mAh·g−1 at 75 mA·cm−2) is 55 mAh·g−1 higher than that of the as-cast alloy, showing great potential for development.

Keywords

• Mg-air battery
• Mg-Ga-Sn
• Discharge performance
• Dissolution-reprecipitation
• Electrochemical behavior