In‐situ Formation of a LiF‐rich Interphase for Graphite Anode Operated at Low Temperatures

Abstract Inorganic LiF is generally a desirable component in solid electrolyte interface (SEI) for graphite anode due to its electronic insulation, low Li + diffusion barrier, high modulus and good chemical stability. Herein, fluorinated carbon (CF x ) was incorporated into graphite material, which exhibited a high discharge potential prior to electrolyte decomposition and in‐situ formed a crystalline LiF‐based SEI with improved Li + diffusion rate. The optimized graphite anode therefore demonstrated a fast‐charging capability with 124 mAh g −1 at high rate of 8 C and a remarkable capacity retention of 83.8 % at the low temperature of −30 °C compared to that at 25 °C. Furthermore, the optimized graphite|LiFePO 4 full cell exhibited a significantly high discharge capacity of 109 mAh g −1 at −30 °C, corresponding to a notable 77.3 % room‐temperature capacity retention. These findings highlight a facile strategy to attain a LiF‐rich SEI for high‐performance lithium‐ion batteries.