Bridging Fundamentals and Practice: Advances in Electrolyte Chemistry for Rechargeable Magnesium‐Sulfur Batteries

Magnesium‐sulfur (Mg‐S) batteries are emerging as promising next‐generation energy storage systems in view of their ultrahigh volumetric energy density, abundant magnesium/sulfur resources, and enhanced safety characteristics. Despite these advantages, the practical development of Mg‐S batteries remains largely constrained by electrolyte limitations. This review provides an overview of recent advances in Mg‐S electrolytes, focusing on synthesis strategies, anion‐cation chemistry, solvation regulation, and electrochemical properties of both non‐nucleophilic and nucleophilic systems. We highlight progress in non‐nucleophilic electrolytes, covering chloride‐containing, chloride‐free, and polymer‐based (gel/solid‐state) systems, and discuss how functional additives and interphase engineering can stabilize the Mg anode, tune sulfur redox pathways, and mitigate the shuttle effect. The remaining challenges and research gaps in Mg‐S electrolytes are outlined, and future directions are proposed to advance practical Mg‐S electrolyte development.