Eutectic Electrolytes Chemistry for Rechargeable Zn Batteries

Rechargeable zinc batteries (RZBs) have proved to be promising candidates as an alternative to lithium-ion batteries due to their low cost, inherent safety, and environmentally benign features. While designing cost-effective electrolyte systems with excellent compatibility with electrode materials, high energy/power density as well as long life-span challenge their further application as grid-scale energy storage devices. Eutectic electrolytes as a novel class of electrolytes have been extensively reported and explored taking advantage of their feasible preparation and high tunability. Recently, some perspectives have summarized the development and application of eutectic electrolytes in metal-based batteries, but their infancy requires further attention and discussion. This review systematically presents the fundamentals and definitions of eutectic electrolytes. Besides, a specific classification of eutectic electrolytes and their recent progress and performance on RZB fields are introduced as well. Significantly, the impacts of various composing eutectic systems are disserted for critical RZB chemistries including attractive features at electrolyte/electrode interfaces and ions/charges transport kinetics. The remaining challenges and proposed perspectives are ultimately induced, which deliver opportunities and offer practical guidance for the novel design of advanced eutectic electrolytes for superior RZB scenarios.