Non-Fluorinated Cyclic Ether-Based Electrolyte with Quasi-Conjugate Effect for High-Performance Lithium Metal Batteries.

Fluorinated ether-based electrolytes are commonly employed in lithium metal batteries (LMBs) to attenuate the coordination ability of ether solvents with Li and induce inorganic-rich interphase, whereas fluorination inevitably introduces exorbitant production expenses and environmental anxieties. Herein, a non-fluorinated molecular design strategy has been conceptualized by incorporating methoxy as an electron-donating group to generate a quasi-conjugate effect for tuning the affinity of Li-solvent, thereby enabling the cyclic ether solvent 2-methoxy-1,3-dioxolane with weak solvation ability and exceptional Li metal-compatibility. Accordingly, the optimized electrolyte exhibits anion-dominant solvation structure for inorganic-rich interphase and fulfills an impressive Li plating/stripping Coulombic efficiency of 99.