Influence of lithium salt, carbonate solvents, and additives on Li-ion batteries performance with biomass-based electrodes

     Biomass-derived electrode materials have gained significant attention in recent years due to their cost-effectiveness, abundance, and sustainability. Among various biomass-derived materials, silica–carbon composite anodes from rice husks have shown great potential for next-generation energy storage systems, particularly in Vietnam. It is necessary to have a holistic investigation of the compatibility of lithium salts, solvents, and additives in purposing energy storage. In this work, we evaluate the carbonate solvents with varied lithium salts to choose the optimal electrolyte. Then, the electrolyte is continually optimized by additives to strengthen safety ability, electrode protection, and battery performance. The full cells show that 1 M LiPF6 in EC: DEC (1:1 v/v) with 5 wt% FEC delivers outstanding capacity and retention, with an initial capacity of 160.7 mAh g⁻¹ and a high-rate discharge capability, maintaining 49.7 mAh g⁻¹ at 2C. Then, full cell solid-electrolyte interphase behaviors were further validated by total resistance measurements, XPS data, and HR-TEM analysis. In detail, FEC contributes to the stability of the SEI layer by enhancing its F-based components, thus protecting the electrodes. As a result, the LiF-rich SEI layer formed with FEC not only facilitates enhanced Li⁺ transport but also significantly improves performance.