Chloride-Free Electrolytes for High-Voltage Magnesium Metal Batteries: Challenges, Strategies, and Perspectives

The demand for high-energy-density and safe energy storage devices has spurred increasing interest in high-voltage rechargeable magnesium batteries (RMB). As electrolytes are the bridge connecting the cathode and anode materials, the development of high-voltage electrolytes is the key factor in realizing high-voltage RMBs. This concept presents an overview of three chloride-free electrolyte systems with wide electrochemical windows, together with the degradation mechanisms and modification strategies at the anode/electrolyte interphase. Finally, future directions in stabilizing Mg anodes and realizing high-voltage RMBs are highlighted.