Affiliation:
1. Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy iChEM (Collaborative Innovation Center of Chemistry for Energy Materials) Fudan University Shanghai 200433 China
Abstract
AbstractInorganic 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 (CFx) 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|LiFePO4 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.