2016 Volume 84 Issue 11 Pages 833-835
The carbon-coated LiFePO4/C cathode active material was successfully synthesized via a glycine-assisted sol-gel method. Glycine was used both as the chelating reagent and the carbon source. The effect of the carbon source on the structural, morphological and electrochemical properties of LiFePO4 are studied in this paper. The structure, morphology and electrochemical performance were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and galvanostatic charge-discharge test. The results indicated that glycine did not affect the crystal structure, but restrained the particle size of LiFePO4/C. The SEM images revealed that the majority of the particles lay between 900 and 5000 nm for pure LiFePO4, while the carbon-coated LiFePO4 particles were from 400 to 900 nm. The LiFePO4/C sample synthesized at 700°C for 8 h delivered the highest initial discharge specific capacity of 163.5 mAh/g, i.e. 96.2% of the theoretical capacity. It retained a high discharge capacity of 112.3 mAh/g over 20 cycles at 1 C rate. The glycine-assisted sol-gel synthesis is favor to obtain the high electrochemical performance of LiFePO4/C.