Influence of pH on Electrochemical Performances of Iron Phosphate (FePO_4·xH_2O) Particles and LiFePO_4/C Composites

摘要

The effect of pH concentrations on the size and morphology of FePO_4·xH_2O particles synthesized in a hydrothermal reactor was investigated in this work. FePO_4·xH_2O was prepared through co-precipitation by employing Fe(NO_3)_3·9H_2O and H_3PO_4 as raw materials. The LiFePO_4 obtained through lithiation of FePO_4·xH_2O by using glucose as a reducing agent at 700°C. The electrochemical performance of LiFePO_4 powder synthesized at 700°C were evaluated using coin cells by galvanostatic charge/discharge. The results indicated that the synthesized LiFePO_4/C composites (pH=2) showed a superior electrochemical capacity of 146 mAh/g and possessed a capacity favorable cycling maintenance at the 0.1C rate and high electronic conductivity.