Abstract
Silica (SiO 2 ) anodes are promising candidates for enhancing the energy density of next‐generation Li‐ion batteries, offering a compelling combination of high storage capacity, stable cycling performance, low cost, and sustainability. This performance stems from SiO 2 unique lithiation mechanism, which involves its conversion to electroactive silicon (Si) and electrochemically inactive species. However, widespread adoption of SiO 2 anodes is hindered by their slow initial lithiation. To address this, research has focused on developing electrochemical “activation protocols” that involve prolonged low‐potential holding steps to promote SiO 2 conversion. Despite these efforts, the complex and multi‐pathway nature of SiO 2 lithiation process remains poorly understood, impeding the rational design of effective activation strategies. By introducing a multi‐probe characterization approach, this study reveals that, contrary to the previously proposed reaction mechanism of SiO 2 anodes, the lithiation process initiates at low potentials with the direct formation of Li 4 SiO 4 and Li x Si. Electrochemical activation potential was found to significantly influence the degree of conversion, with 10 mV identified as the optimal cut‐off potential for maximizing SiO 2 utilization. These findings provide key enablers to unlock the full potential of SiO 2 anodes for battery technology.