Synthesis and electrochemical performance of LiFePO 4/C prepared by a new method

Abstract

LiFePO 4/C composite was prepared at 700 ∘C for 5 h by gas-phase diffused permeation (DP) and its electrochemical properties were improved by Al 3+ diffused permeation on the surface of LiFePO 4/C. The structural and electrochemical properties were examined by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), cyclic voltammetry (CV) and charge–discharge cycling performance. XRD and SEM analysis showed that LiFePO 4/C and Al 3+ permeation LiFePO 4/C are olivine-type phase and the average particle size was about 100–250 nm with uniform distribution. LiFePO 4/C exhibits initial discharge capacity of 131.9 and 101 mAh g −1 at 0.1 C and 3 C, respectively. While the cathode material of Al 3+ permeation LiFePO 4/C shows a better performance and has initial discharge capacity of 152.9 and 108.3 mAh g −1 corresponding to 0.1 C and 3 C.