Stereoactive Metallic Vanadium Oxide Barriers to Boost Silicon-Based Lithium-Ion Storage

Despite the intensive efforts devoted to confining silicon (Si)-based materials with heteromatrices for high-energy-density lithium-ion batteries, addressing practical issues with rationally incorporated stereoactive matrix is still a significant challenge. This study presents an electrochemical-active, metallic matrix for boosting Si-based lithium-ion storage. By employing a straightforward strategy involving mechanical ball-milling and controllable phase transformation, spatially confined Si-based composites enabled by metallic vanadium oxide (VO_0.9) barriers can be readily achieved. The scalable interface engineering allows for expanded transportation channels and maintained structural integrity, which can be well established in both SiO_x and Si cases. Endowed with promoted electron conduction as well as fast lithium-ion diffusion, the optimal Si-based composite electrodes demonstrate remarkable lithium storage performance, that is, an initial Coulombic efficiency of 81%, and a high specific capacity of 1249 mAh g⁻¹ at 500 mA g⁻¹ after 100 cycles. Notably, full cells coupled with a commercial LiCoO₂ cathode are demonstrated, affording impressive specific energy of 440 Wh kg⁻¹ at high mass loading. This work provides a cost-effective approach to promoting the practical application of Si-based anodes, which also holds promise for extension towards energy-related applications and beyond.