▎ 摘　　要

Graphene-modified mesoporous LiFePO4 microsphere composites were synthesized by a hydrothermal method and subsequent annealing. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FT-IR) spectroscopy, and galvanostatic charge-discharge techniques were used to characterize the morphology, structure and electrochemical performance of the resulting composites. The graphene-modified LiFePO4 microspheres exhibited a high discharge capacity of 141 mAh . g(-1) at 1C, and 105 mAh . g(-1) at 50C, while LiFePO4/C only delivered 137 mAh . g(-1) at 1C, 64 mAh . g(-1) at 50C in an aqueous electrolyte of 2 mol . L-1 LiNO3. The graphene-modified LiFePO4 exhibited excellent cyclability compared with LiFePO4/C, with a capacity retention of about 83.7% after 60 cycles versus about 70.2% for LiFePO4/C. The improved electrochemical performance is attributed to the formation of a three-dimensional (3D) graphene network.