Regulation of SEI Formation by Anion Receptors to Achieve Ultra‐Stable Lithium‐Metal Batteries

Abstract Despite high specific capacity (3860 mAh g −1 ), the utilization of Li‐metal anodes in rechargeable batteries are still hampered due to their insufficient cyclability. Herein, we report an anion‐receptor‐mediated carbonate electrolyte with improved performance and can ameliorate the solid electrolyte interphase (SEI) composition comparing to the blank electrolyte. It demonstrates a high average Coulombic efficiency (97.94 %) over 500 cycles in the Li/Cu cell at a capacity of 1 mAh cm −2 . Raman spectrum and molecular modelling further clarify the screening effects of the anion receptor on the Li + ‐PF 6 − ion coupling that results in the enhanced ion dynamics. The X‐ray photoelectron spectroscopy (XPS) distinguishes the disparities in the SEI components of the developed electrolyte and the blank one, which is rationalized by the molecular insights of the Li‐metal/electrolyte interface. Thus, we prepare a 2.5 Ah prototype pouch cell, exhibiting a high energy density (357 Wh kg −1 ) with 90.90 % capacity retention over 50 cycles.