Dual Lithiophilic Li2O@LiZn sites towards practical Lithium metal batteries

Lithium metal anode is regarded as the “holy grail” of anode materials for Li-metal batteries (LMBs) because of its ultrahigh-specific capacity. However, the uncontrollable growth of “hostless” Li dendrite in the Li anode has a vital impact on its practical applications. Herein, the ultra-lightweight 3D carbon fiber is proposed to construct a Li metal anode via molten Li infusion with the aid of ZnO nano-coral. The atom probe tomograph (APT) manifests that the Li can be doped into Zn at the atomic scale and form Li₂O on ZnO nano-coral, realizing a strong lithiophilic interface for uniform Li deposition. The in-situ TEM and DFT calculation confirms that the formed LiZn/Li₂O not only acts as nucleation sites for lowering the Li diffusion barrier but also improves interfacial ionic conductivity for homogenizing Li-ion flux. As a result, the Li₂O@LiZn-LCF@Li anode exhibits excellent cycle stability over 400 h under ultrahigh Li utilization of 70.7 %. The full cell paired with LiFePO₄ delivers a high discharge capacity of 142.9 mAh g⁻¹ and maintains a high-capacity retention of 93.3 % after 100 cycles under a harsh condition of low N/P (2.08). The strategy provides a broad prospect for developing composite metal anodes in practical high-energy-density LMBs.