Study on structure and electrochemical performance of LiFePO4/C modified by PANI

LiFePO4 has attracted broad attention as a promising cathode material for lithium ion batteries. The key issues related to LiFePO4 performance lie on the intrinsic characteristic of poor diffusion of lithium ions through an interface between LiFePO4 and FePO4. To explore the effect of polyaniline on performances, LiFePO4/C cathode materials were prepared via hydrothermal method, using glucose as a carbon source and polyaniline as a modifier. The samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), galvanostatic charge-discharge test and cyclicvoltammetry (CV). The results show that the olivine-type phase of LiFePO4/C is not changed by polyanilines and LiFePO4/C is composed of relatively large particles of about 400nm and some nano-sized polyaniline particles, which favor the electronic conductivity. The LiFePO4/C cathode material modified by 10% polyaniline has the highest uniformity. It delivers the capacity of 167.9mAh.g(-1) at 0.1C, and has good reversibility and high capacity retention.