Structure Controlled Mg Alloy as Anode for Magnesium-air Battery Via Pressure-less Sintering Technique

Abstract

Magnesium-air batteries have been considered as a promising electrochemical energy storage device because Mg is known as element on the earth crust, has a high reactivity and relatively high safety and low toxicity. Despite a relative high voltage and energy density of the Mg-air batteries, there are several problems such as high polarization and low coulombic efficiency. To solve the existing problems of Mg-air batteries, a lot of studies are conducted to improve the electrochemical performance by alloying Mg with other materials and controlling Mg-alloy morphology. In this study, pressure-less sintering was used to fabricate 3D cellular structured Mg alloy anode. Different types of Mg-Al alloy (such as chip, sheet and powder) were used as raw material. Fine Mg-Al alloy powder was milled via high energy milling of commercial Mg-Al alloy. The materials were consolidated at the initial stage of sintering to increase the surface area of anodes. 3D cellular structured Mg alloy anodes consolidated at various sintering conditions in terms of porosity, microstructure and discharge performance. Through the results mentioned above, we can propose the optimized sintering condition for Mg-Al alloy anode.