Lithiophilic 3D-Si/SiOx host for dendrite free lithium metal battery via simple magnesiothermic reduction process.

In the development of renewable energy sources, batteries are considered the best option for energy storage. High energy density and high performance are key demands for emerging technologies. Lithium-metal batteries (LMBs) are considered promising candidates for storing generated energy. However, the formation of lithium dendrites and infinite volume expansion during cycling are serious limitations in current LMB applications. 3D-structured anodes have received considerable attention as an effective solution to overcome these problems. Herein, we synthesize a lithiophilic 3D-Si/SiO_x host for LMBs via a simple magnesiothermic reduction process (MRP). The 3D porous SiO_x structure provides a large specific surface area, which reduces local current density and offers ample space for Li deposition. The 3D-Si/SiO_x anode not only accommodates volume changes but also demonstrates homogeneous, dendrite-free lithium deposition with a high coulombic efficiency of more than 99% at 0.1, 0.5, and 1.0C. The symmetric cell composed of prelithiated (4 mAh/cm²) 3D-Si/SiO_x shows stable long-cycle performance for over 350 hours. By utilizing a single porous particle material with surface-limited lithiophilic properties, rather than the conventional complex 3D lithium anode designs (which typically involve hierarchical structures and lithium-friendly seed materials), this work provides new insights into the design of 3D lithium metal anodes.