Self‐Assembled Lithiophilic Interface with Abundant Nickel‐Bis(Dithiolene) Sites Enabling Highly Durable and Dendrite‐Free Lithium Metal Batteries

Abstract

Abstract Despite its ultrahigh theoretical capacity and ultralow redox electrochemical potential, the practical application of lithium metal anodes is still hampered by severe dendrite growth and unstable solid electrolyte interphase (SEI). Herein, a self‐assembled lithiophilic interface (SALI) for regulating Li electroplating behavior is constructed by introducing a meticulously synthesized Ni‐bis(dithiolene)‐based molecule (NiS 4 ‐COOH) into a hybrid fluorinated ester‐ether electrolyte. The NiS 4 ‐COOH molecules with carboxyl functional groups can spontaneously anchor on the Li metal surface to form a SALI, whose abundant Ni‐bis(dithiolene) sites can effectively reduce the initial Li deposition overpotential and guide the subsequent uniform Li electrodeposition. Moreover, due to the interaction between the coordination unsaturated Ni atom and the negatively charged PF 6 − , the NiS 4 ‐COOH additive can significantly change the ionic coordination environment in the electrolyte, which is greatly conducive to suppressing PF 6 − decomposition, optimizing SEI composition and accelerating Li‐ion transfer. Consequently, the NiS 4 ‐COOH‐modified electrolyte leads to impressive electrochemical performance of Li||LiFePO 4 and Li||LiNi 0.8 Co 0.1 Mn 0.1 O 2 batteries, delivering ultrahigh Coulombic efficiencies, considerable capacity retention, and good rate performance even at high areal active material loadings. This study presents the great potential of SALIs derived from multifunctional metal‐organic hybrid electrolyte additives toward high‐specific‐energy Li metal batteries.