Affiliation: | 1. Helmholtz Institute Ulm (HIU), Helmholtzstraße 11, 89081 Ulm (Germany), Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021 UlmKarlsruhe, Germany Contribution: Conceptualization (lead), Project administration (lead), Writing - original draft (lead), Writing - review & editing (supporting);2. Helmholtz Institute Ulm (HIU), Helmholtzstraße 11, 89081 Ulm (Germany), Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021 UlmKarlsruhe, Germany Present address: ELETTRA Synchrotron of Trieste, 34012 Basovizza Trieste, Italy Contribution: Writing - original draft (supporting), Writing - review & editing (supporting);3. Hong Kong Quantum AI Lab, 17 Science Park West Avenue, Hong Kong, China Contribution: Writing - review & editing (equal);4. Helmholtz Institute Ulm (HIU), Helmholtzstraße 11, 89081 Ulm (Germany), Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021 UlmKarlsruhe, Germany |
Abstract: | Non-flammable ionic liquid electrolytes (ILEs) are well-known candidates for safer and long-lifespan lithium metal batteries (LMBs). However, the high viscosity and insufficient Li+ transport limit their practical application. Recently, non-solvating and low-viscosity co-solvents diluting ILEs without affecting the local Li+ solvation structure are employed to solve these problems. The diluted electrolytes, i.e., locally concentrated ionic liquid electrolytes (LCILEs), exhibiting lower viscosity, faster Li+ transport, and enhanced compatibility toward lithium metal anodes, are feasible options for the next-generation high-energy-density LMBs. Herein, the progress of the recently developed LCILEs are summarised, including their physicochemical properties, solution structures, and applications in LMBs with a variety of high-energy cathode materials. Lastly, a perspective on the future research directions of LCILEs to further understanding and achieve improved cell performances is outlined. |