Sulfone-based high-voltage electrolytes for high energy density rechargeable lithium batteries: Progress and perspective

Further enhancement in the energy density of rechargeable lithium batteries calls for high-voltage cathode materials and stable anodes, as well as matched high-voltage electrolytes without compromising the overall property of batteries. Sulfone-based electrolytes have aroused great interest in recent years owing to their wide electrochemical window and high safety. However, significant challenges such as the complexity of synthesis, high melting point (typically above room temperature), high viscosity, and their poor compatibility with graphite-based anodes have drastically impeded their practical applications. In this review, recent progress of sulfone solvents in high energy density rechargeable lithium batteries is summarized theoretically and experimentally. More importantly, general improvement methods of sulfone-based electrolytes, such as adding additives and cosolvents, structural modifications of sulfone, superconcentrated salt strategy are briefly discussed. We expect that this review provides inspiration for the future developments of sulfone-based high-voltage electrolytes (SHVEs) and their widespread applications in high specific energy lithium batteries.