Batch-Scale Synthesis and Interfacially Enhanced Stability of Silicon Suboxide-Based Anodes toward High-Performance Lithium-Ion Batteries

Abstract

SiO x anode materials are among the most promising candidates for next-generation high-energy-density lithium-ion batteries (LIBs). However, their commercial application is hindered by poor conductivity, low initial Coulombic efficiency (ICE), and an unstable solid electrolyte interface. Developing cost-effective SiO x anodes with high electrochemical performance is crucial for advanced LIBs. To tackle these issues, this study utilized APTES as a silicon source and carbon nanotubes (CNTs) as additives to prepare a T-SiO x / C/CNTs composite material with N doping and in situ carbon coating using a "molecular assembly combined with controlled pyrolysis" strategy under mild conditions. The in situ carbon coating, formed by the pyrolysis of organic groups on the molecular precursor, effectively protects the inner SiO x active material. The introduced CNTs enhance electron migration and improve the rigidity of the carbon coating layer. The prelithiated T-SiO x @C/CNTs electrode achieves an ICE of 91.6%, with a specific capacity of 622 mAh g −1 after 400 cycles at 1 A g −1 and 475.8 mAh g −1 after 800 cycles. Full cell tests with commercial NCM811 cathodes further demonstrate the potential of T-SiO x @C/CNTs as a highly promising anode material. This work provides some insights into the rational design of advanced anode materials for LIBs, paving the way for their future development and application.