Robust 3D carbon host decorated with in-situ generated Li–Si alloy and Li₃N for Li metal anodes

Lithium metal batteries hold a great promise for next-generation high-energy-density energy storage devices. However, severe Li dendrite growth and low Coulombic efficiency limit the application of lithium metal as anodes in Li batteries. Herein, we report a novel N-doped carbon host decorated with in-situ generated Li–Si alloy and Li₃N for Li metal anode, showing a high theoretical specific capacity of 3090.0 mAh g⁻¹. The as-prepared lithium composite (SiO₂-N-CP@Li) electrode maintains stable cycling for over 960 h at 1.0 mA cm⁻²/1.0 mAh cm⁻² and still has excellent stability (>900 h) especially at a high current density of 5.0 mA cm⁻². Furthermore, when the SiO₂-N-CP@Li anode is paired with LiFePO₄ (LFP) cathode, the assembled full cell manages to deliver an impressive cycling performance for 450 cycles at 1C. This work offers a new insight for the rational design and utilization of Li metal anode in the next-generation high-energy-density batteries.