Effect of magnetic treatment on microstructure and cycle performance of LiFePO4 /C cathode material

Abstract LiFePO4/C composite was prepared by hydrothermal synthesis along with a magnetic treatment method. The LiFePO 4 /C composite synthesized without magnetic treatment is an integrated rhombic shape crystal, whereas the LiFePO 4 /C material synthesized with magnetic treatment presents a rhombus shape which is self-assembled by a number of small crystal particles with an average size of about 100 nms. The capacity retention for the LiFePO 4 /C cathode material synthesized without magnetic treatment is only 77% after 30 charge–discharge cycles at 0.2 C, but the LiFePO 4 /C composite synthesized with magnetic treatment has a capacity retention of 100% after 100 charge–discharge cycles at 1 C and 5 C. It suggests that magnetic treatment can remove Fe 3+ cations effectively during the preparation process and enhance the cycle performance of the LiFePO 4 /C material.