Advanced Electrolytes Enabling Safe and Stable Rechargeable Li-Metal Batteries: Progress and Prospects

Rechargeable Li-metal batteries (RLBs) can boost energy yet possess poor cycle stability and safety concerns when utilizing carbonate electrolytes. Countless effort has been invested in researching and developing electrolytes for RLBs to obtain stable and safe batteries. However, only few existing electrolytes meet the requirements for practical RLBs. In this perspective, the challenges of organic liquid electrolytes in the application in RLBs are summarized, and requirements for electrolytes for practical RLBs are proposed. This perspective briefly reviews the recent achievements of electrolytes (liquid- and solid-state) for RLBs and analyzes the corresponding drawbacks of each electrolyte. Further, possible solutions to the existing shortcomings of various electrolytes are proposed. In particular, this perspective outlines the development strategy of in situ gelation electrolytes, accompanied by a call for people using pouch cells to evaluate performance and paying more attention to battery safety research. This perspective aims to expound on the challenges and the possible research directions of RLBs electrolytes to promote practical RLBs better.