The Synthesis, Structure and Electrochemical Performances of Lithium Iron Phosphate

The lithium iron phosphate cathode materials were synthesized by solid-state reaction combined high-rate ball milling under the temperature ranging from 400 ℃ to 700 ℃.The crystalline structure, morphology of particles, and electrochemical performance of the sample were investigated by X-ray diffraction, scanning electron microscopy and charge-discharge test. The results showed that the sintering temperature had great influences on the crystal structure, morphology and electrochemical performances of LiFePO4. The sample synthesized under 600℃ showed the best charge-discharge performances with the first specific discharge capacity of(128.8) mAh/g and the 15th specific discharge capacity of 129.1 mAh/g at 0.1C rate, each charge-discharge cycling efficiency being 99.7%. Also the sample showed good electrochemical performances under higher temperatures.