Regulating Uniform Lithium Plating and Stripping on a Lithium Carbonate-Deposited Lithium Metal Surface

Li metal can be the ultimate choice of anode for high-energy-density Li metal batteries. However, Li metal can easily react with air to form lithium carbonate on its surface. In this work, we report an ion-exchange chemistry method to rapidly deposit an artificial solid electrolyte interphase (SEI) composed of hybrid Zn/LiZn alloys on the lithium carbonate-deposited Li metal surface. The as-formed Li-affinity Zn/LiZn alloys can effectively regulate homogeneous Li nucleation and stabilize the Li/electrolyte interface for uniform Li plating and stripping during long-term cycling. Furthermore, dendrite-free cycling is demonstrated in full cells pairing the modified Li-metal anodes with LiNi0.8Co0.10Mn0.10O2 (NCM811) cathodes at both room temperature and 55 °C. The Li/Li2CO3@Zn/LiZn||NCM811 full cell achieves an extended lifespan exceeding 300 cycles, with significantly improved capacity retention (76.6%) and greatly reduced voltage decay (0.07 V). This work proposes a multiphase surface engineering strategy, integrating inorganic compounds (e.g., Li2CO3) and alloys (e.g., Zn/LiZn), to stabilize Li metal anodes, which could be enlightening for the design of stable artificial SEI for long-life Li metal batteries.