Amphiphobic Solvent-Mediated Relay Push-Escape Strategy for Highly Efficient Lithium-Metal Batteries

Lithium-metal batteries promise high-energy-density, wide operating temperature ranges, and fast charging. However, integrating these attributes remains a formidable challenge, as it necessitates an electrolyte that concurrently delivers high ionic conductivity, low solvation energy, low melting point, and the ability to form a stable electrode-electrolyte interphase (EEI), a feat elusive to conventional formulations. Here, we successfully address this challenge with a "relay push-escape" strategy using amphiphobic hexafluoroisopropyl methyl ether. Its anion-repulsive Coulombic field and steric hindrance transform conventional 1 M LiFSI-DME electrolyte into L4DF electrolyte, triggers a novel mechanism that drives anions into the inner Li⁺ solvation sheaths, displacing DME solvents to form a contacted ion-pair and aggregative ion-pair-dominated structure. The resulting L4DF electrolyte facilitates rapid Li⁺ desolvation and fosters the formation of a stable, anion-derived LiF-rich EEI. As a result, the L4DF electrolyte demonstrates exceptional compatibility with lithium-metal, showing high Coulombic efficiency of 99.7%. The LiNi_0.8Co_0.1Mn_0.1O₂||Li half-cell achieves 91.2% capacity retention after 1000 cycles and outstanding performance under 5 C fast-charging and low-temperature conditions. Remarkably, a 5.52 Ah pouch-cell reaches an energy density of 502.3 Wh kg^-1 while retaining 87.6% of its capacity for 260 cycles. This work paves the way for the precise design of electrolytes for advanced batteries.