Synthesis and Characterization of LiFe0.7Mn0.3PO4/C Cathode Material for Lithium Ion Batteries

摘要

LiFe0.7Mn0.3O4/C was synthesized at 650°C by solid-state reaction. Structure, surface morphology and electrochemical properties of LiFe0.7Mn0.3O4/C were characterized by X-ray diffraction, scanning electron microscopy, and electrochemical measurement, respectively. Results show that LiFe0.7Mn0.3O4 shares a single olivine structure. The morphologies of LiFe0.7Mn0.3O4 are greatly affected by the addition of carbon. The LiFe0.7Mn0.3PO4/C has a small particle size of 100～200nm and carbon is coated on the surface of LiFe0.7Mn0.3O4 uniformly. LiFe0.7Mn0.3O4/C demonstrates high reversible capacity and perfect cycling performance, and excellent rate capability: the reversible capacity of about 141 mAh·g-1 at a current rate of 0.1C and the capacity loss per cycle is only 0.19% after cycling 60 times, while that of LiFe0.7Mn0.3PO4 is 0.53% , suggesting the electrochemical performance of LiFe0.7Mn0.3PO4 is improved effectively by addition of carbon.