Unlocking the influence of pitch-based and acetylene-based carbon coating on the electrochemical performance of SiO anodes: bridging insights from half-cell to full-cell studies

Silicon monoxide (SiO) has garnered significant attention as a prominent candidate for high-energy-density lithium-ion batteries (LIBs) owing to its reduced volume expansion and enhanced cycling stability compared to pure silicon (Si). However, the effect of carbon layers derived from different carbon sources on the electrochemical performance of SiO in both half and full cells has not been comprehensively studied, and the industrial consensus regarding the selection of carbon sources for SiO remains elusive. Herein, a systematic comparative evaluation was conducted to analyze the physicochemical properties and electrochemical behaviors of SiO with two different carbon layers. Additionally, comprehensive assessments were carried out to investigate the electrochemical performance of SiO employing two distinct carbon coating methods in 6 Ah pouch full-cell configurations, where SiO coated acetylene-based carbon exhibits advantages in cycling stability and Li+ kinetic. In industrial SiO carbon coating processes, it is advisable to prioritize acetylene-derived carbon using chemical vapor deposition (CVD) characterized by a high degree of graphitization, enhanced electrical conductivity, and uniform surface coverage. The investigation rooted in electrochemical performance of different carbon layers on SiO in both half-cell and full-cell configurations, provides fundamental insights for the advancement of research in silicon-based anodes' development.