Effects of Deformation Microstructures on the Electrochemical Properties of Mg-Hg-Ga Alloy Anode

Abstract

Mg-Hg-Ga alloy is one of the anode materials for seawater-activated batteries. Here, Mg-3.0 wt%Hg-3.0 wt%Ga alloys were prepared by extrusion and rolling and the microstructure of the Mg-3.0 wt%Hg-3.0 wt%Ga alloy after plastic deformation was studied. The effects of deformation microstructures on the discharge properties and corrosion behavior of the alloys were investigated by galvanostatic discharge, potentiodynamic polarization, electrochemical impedance spectra experiments, and Mg/AgCl battery test. The results show that the microstructure of the extruded alloy is uniform, and the corrosion activity and discharge activity of the extruded alloy are relatively weak. Hot rolling deformation refines the grains and promotes the precipitation of the Mg5Ga2 phase distribute more dispersively, which results in faster and more uniform activation of the alloy, thus improving the corrosion activity and discharge activity of the Mg-3.0 wt%Hg-3.0 wt%Ga alloy. The results of galvanostatic discharge in half battery and Mg/AgCl battery discharge tests show that rolling deformation improves the discharge properties of the alloy, and the alloy with 78% rolling reduction has the best discharge performance.