High‐Performance Silicon‐Based Anodes Enabled by Solid‐State Sintering of Li–V–Si–O Interfacial Layer

Silicon anodes, with a theoretical capacity far exceeding that of graphite, are regarded as a key candidate for boosting the energy density of lithium‐ion batteries. However, the severe volume expansion during lithiation/delithiation often causes structural collapse and interfacial instability. In this work, we address the trade‐off in ASEI‐modified silicon anodes between suppressing excessive lithiation‐induced volume expansion and maintaining sufficient interfacial electrochemical activity. A scalable solid‐state sintering strategy is developed to construct a Li–V–Si–O artificial solid electrolyte interphase (ASEI) in situ on silicon particles, which regulates lithiation depth to mitigate volumetric strain while preserving reversible lithiation activity and interfacial stability. The obtained composites exhibit significantly improved electrochemical properties, including a high initial delithiation capacity of 2073.5 mAh g −1 with an initial Coulombic efficiency (ICE) of 84.1%. Even at 2.0 A g −1 , the electrode retains 972.7 mAh g −1 after 100 cycles, corresponding to 82.6% capacity retention. The method combines simplicity, low cost, environmental friendliness, and electrochemical robustness, offering a feasible pathway for large‐scale application of silicon anodes.