Engineering a Dynamic Alloy–Fluoride Interface via a Co-Placement Gas-Phase Strategy for Stable Lithium Metal Anodes

Lithium metal batteries (LMBs) hold great promise for next-generation high-energy-density energy storage systems, but suffer from uneven Li nucleation and unstable interfaces. Here, a scalable coplacement gas-phase reaction strategy is developed to construct an adaptive alloy–fluoride interface on nickel mesh current collectors, enabling one-step in-situ formation of a uniform Ni3Sb/NiF2 layer. The lithiophilic Ni3Sb alloy effectively lowers the lithium nucleation barrier and guides uniform lithium deposition. Upon cycling, NiF2 is transformed into a LiF-rich interphase, which stabilizes the electrode/electrolyte interface and homogenizes Li+ flux. The combined interface enables durable and uniform Li plating/stripping under long-term cycling. Consequently, the Ni3Sb/NiF2-modified anode achieves stable cycling for over 2600 h in symmetric cells and delivers 83.1% capacity retention after 240 cycles in LiFePO4 full cells with a high areal capacity of 10 mAh cm–2. This work provides a facile and scalable strategy for engineering multifunctional interfaces toward practical LMBs.