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

LiFePO4/C composite was prepared by hydrothermal synthesis along with a magnetic treatment method. The LiFePO4/C composite synthesized without magnetic treatment is an integrated rhombic shape crystal, whereas the LiFePO4/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 LiFePO4/C cathode material synthesized without magnetic treatment is only 77% after 30 charge-discharge cycles at 0.2 C, but the LiFePO4/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 Fe3+ cations effectively during the preparation process and enhance the cycle performance of the LiFePO4/C material.