Study of Key Factors Influencing Electrochemical Reversibility of Magnesium Deposition and Dissolution

The electrochemical magnesium deposition and dissolution on metal substrates with high cycling efficiency can be realized in both organic electrolyte and ionic liquid . The effect of metal substrates (Ag, Ni, and Cu) on magnesium deposition–dissolution was studied by cyclic voltammograms and charge–discharge tests of coin cells, and better results were obtained using silver as the substrate in both the electrolytes. X-ray diffraction analysis reveals that the deposited magnesium can react with silver substrate to form silver–magnesium alloy, which decreases the overpotential of electrochemical magnesium deposition–dissolution and promotes the cycling efficiency. It was observed that morphology of magnesium deposit and interfacial impedance developed from the above-mentioned electrolytes varied markedly, leading to different electrode performances such as overpotential in the initial cycles and cycle life.