Improvement of the Electrochemical Performance of LiFePO_4 Cathode Composite Material Using a In Situ Pyrolysis Carbon Synthesis Procedure

摘要

LiFePO_4/Carbon composite cathode material was prepared by pelleting and subsequent pyrolytic cracking process in N_2 atmosphere with carbon source of polyvinyl alcohol (PVA). XRD crystal analysis indicates that single LiFePO_4 phase and amorphous carbon can be found in the products. SEM observation shows a special micro-morphology of sample, which is favorable for enhancement of electrochemical properties. The discharge capacity of the LiFePO_4/C composite was 135 mAh/g, close to the charge capacity of 153 mAh/g at low rate of 0.1 C. At 0.2C, the specific capacity was about 117.4 mAh/g, which is satisfied for power source of Electric Vehicle for its flat discharge platform.