Fe 0 . 9 Cu 0 . 1 Li 0 . 1 ] PO 4 / C cathode material with enhanced electrochemical properties

LiFePO4 is an effective battery material which has gained global focus. In this study, we prepared a novel Cu-doped Li[Fe0.9Cu0.1Li0.1]PO4/C cathode material via a carbothermal reduction method using glucose as carbon source. X-ray diffraction (XRD) patterns and Rietveld refinement on the samples are consistent with the orthorhombic phase and showed that the substituting Cu ions and excess Li ions occupy the Fe sites. The micro-morphology of the samples indicates that Cu doping can decrease the particle size and maintain the crystal structure of LiFePO4/C. XP spectra confirmed that the surface oxidation states of Fe and Cu are +2 and +1, respectively. The as-prepared Li[Fe0.9Cu0.1Li0.1]PO4/C composite exhibits enhanced initial discharge capacity (148.8 mA h g ) compared to the un-doped LiFePO4/C. The discharge capacity remains at 149.8 mA h g 1 after 50 cycles at a rate of 0.2C, which displayed an excellent cycling stability. Furthermore, the cyclic voltammetry (CV) and electrochemical impedance spectra (EIS) results showed that the Cu-doped LiFePO4/C composite exhibits a higher lithium-ion diffusion coefficient and lower charge transfer resistance than the undoped counterparts. This study presents a novel Cu-doped LiFePO4/C cathode material with enhanced electrochemical properties, which could be potentially applied as a battery material.