“Water‐in‐Eutectogel” Electrolytes for Quasi‐Solid‐State Aqueous Lithium‐Ion Batteries

The development of high safety lithium-ion batteries (LIBs) is greatly impeded by the flammability and leakage concerns typical organic solvent-based electrolytes. As one alternative classes electrolytes, hydrogel electrolytes exhibit safety, flexibility, low cost, are benign to environment. However, narrow electrochemical stability window (ESW) restricts operating voltage battery cells. Here, a new class “water-in-eutectogel (WiETG)” electrolyte reported, fabricated combining with “deep eutectic solvent” (LiTFSI in acetamide). obtained WiETG exhibits non-flammability, ionic conductivity, wide ESW. LiMn2O4||Li4Ti5O12 cells good cycling stability, safety. This newly developed not only broadens ESW but also opens perspective on future directions guidance for design flexible LIBs beyond.