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Many researchers have been working to explore a candidate for commercialized LiCoO2 which is expensive and oxidatively unstable.Lithium iron phosphate is of great interest as a cathode for lithium iron batteries due to its low lost and environmental benignancy.Olivine-type LiFePO4 has a theoretical specific capacity of 170mAhg-1.However,LiFePO4 has disadvantages such as low conductivity and low tap density.Modifying LiFePO4 particles with conductive additives and preparing nanoparticles are proved effective to overcome its low conductivity.Recently,Ying et al.found that powders composed of spherical particles have higher density than powders of irregular shapes.However,spherical LiFePO4 particles prepared by controlled crystallization method or by spray pyrolysis correlated with complicated manipulation or expensive device.In this study,uniform spherical LiFePO4 particles were prepared by homogeneous precipitation method and subsequent heat treatment.The influences of the phosphate buffer solution on the particle formation were investigated.The electrochemical performances were studied and discussed.H3PO4 (85%) and NaH2PO4 were mixed to form a phosphate buffer solution ([PO4 3-] =0.3M).The aqueous solution of FeCl3 (0.1M) was added slowly to the phosphate buffer solution under magnetic stirring.The mixed pellucid solution was sealed and kept in an oven at 60℃ for 24h before the ivory-white precipitate was collected.The as-prepared precursor was ground with sucrose and then sintered at 350℃ for 5h in flowing argon.The mixture was then reground and sintered at 650℃ for 10 under argon.The morphology,the structure and the composition of the particles were investigated by scanning electron microscopy (SEM),X-ray diffraction (XRD),energy dispersive spectroscopy (EDS).The electrochemical performances of the sample were analyzed with electrochemical impedance spectroscopy (EIS) and chare-discharge test.The function of phosphate buffer solution on the formation of precipitation was discussed.The influences of aging temperature and time on the particle size were studied.