Fast Li Ion Flux LiF‐Rich SEI Inducing Spatially‐Confined Deposition for Dendrite‐Free Li Metal Anode

ABSTRACT Lithium (Li) metal, with its ultra‐high theoretical specific capacity and low redox potential, is a promising anode material, yet uncontrollable dendrite growth limits its practical use. Confining Li deposition from one‐dimensional dendritic to three‐dimensional spherical growth is an effective solution. Herein, we propose a synergistic strategy catalyzed by Li‐Au alloy nucleation sites to generate a LiF‐rich solid electrolyte interphase layer. This achieves low Li nucleation potential and high interfacial ion transport kinetics, making Li deposition reaction‐controlled (leading to spherical Li) instead of diffusion‐controlled processes (leading to dendritic Li). Symmetric cells with the modified Li electrode cycle nearly 7500 h (18,000 cycles) at 10 mA cm −2 . LiFePO 4 (LFP) full cells retains 80.3% of their initial capacity after 1000 cycles at 2C; LiCoO 2 full cells demonstrated a capacity of 153 mAh g −1 at an ultra‐high 40C (7.3 mA cm −2 ) rate. Even at a low N:P ratio of 1.4, the LFP full cell can still be stably cycled for over 200 cycles at 1C (1.8 mA cm −2 ) while delivering a high capacity of 151.5 mAh g −1 . This scalable interfacial design strategy provides important insights for the preparation of dendrite‐free Li anodes to improve battery safety.