Electrochemical performance of NiO-doped LiFePO4/C cathode materials prepared from amorphous FePO4 · xH2O

LiFePO 4 /C composites are prepared from amorphous FePO 4 · x H 2 O and are modified with NiO (0.0, 0.01, 0.02, 0.03, and 0.04 mol) by using a solid-state reaction process with a spex milling system. The crystalline structure and the morphology of synthesized powders have been characterized by using X-ray diffraction (XRD) and scanning electron microscope (SEM). The XRD patterns indicate a complete solid solution for all the NiO-doped LiFePO 4 /C composites. The SEM images show that the sizes of the particles produced are distributed in the range of 200 − 300 nm. The electrochemical performances have been evaluated by using an impedance measurement and a galvanostatic charge/discharge test. The initial properties and impedance measurement reveal different improvements for different amounts of NiO doping in LiFePO 4 /C. A maximum capacity of 158.8 mAh/g at 0.1 C has been achieved LiFePO 4 /C doped with NiO at 0.01 mol. The present work reveals that the newly processed composite of LiFePO 4 /C doped with a small amount of NiO may be a promising material for using in a lithium-ion battery.