Novel Synthesis of Plate-like LiFePO4 by Hydrothermal Method

Lithium iron phosphate (LiFePO4) was prepared by hydrothermal synthesis method using FeSO4·7H2O and LiH2PO4 as resource of Li and Fe. The ratio of Li: Fe was maintained 1:1. The results suggested that pH value played a crucial role in the synthesis of LiFePO4, especially for the generation of impurities. We found that adding citric acid to the precursor was an effective way for chelating ferrous ions, thereby preventing the undesirable iron compounds during hydrothermal treatment. The particle morphology and the crystal orientation of the prepared LiFePO4 particles were investigated by the XRD and SEM results. The X-ray diffraction pattern of the samples indicated that single-phase LiFePO4 were successfully synthesized by hydrothermal method with a stoichiometric 1:1 ratio of Li :Fe.