Eutectic Electrolytes for High‐Performance Lithium/Sodium Metal Batteries

Abstract Lithium/sodium metal batteries have attracted extensive attention due to their high energy density. However, they generally suffer from serious dendrite growth during the charge/discharge process, leading to fast capacity degradation and grievous safety hazards. Eutectic electrolytes with the advantages of high ionic conductivity, wide electrochemical windows, and excellent thermal stability have emerged in recent years as a promising candidate for stable lithium/sodium metal batteries. In this review, the recent progress of eutectic electrolytes for lithium/sodium metal batteries is systematically summarized. First, the formation mechanisms and physicochemical properties of eutectic electrolytes are introduced. Subsequently, the recent achievements of eutectic electrolytes to boost electrochemical performance (including cycle life, fast‐charging capability, high‐voltage stability, and temperature tolerance) of lithium/sodium metal batteries are overviewed. In addition, the further research direction for the development of eutectic electrolytes for lithium/sodium metal batteries is proposed. It is believed that this review can provide theoretical guidance for the efficient design of high‐performance eutectic electrolytes.