High-rate electrode material 2LiFePO4·Li3V2(PO4)3@carbon/graphene using the in situ grown Fe4(VO4)4·15H2O precursor on the surface of graphite oxide

Abstract

2LiFePO₄·Li₃V₂(PO₄)₃@carbon/graphene (2LFP·LVP@C/G) as a cathode material, based on an in situ grown Fe₄(VO₄)₄·15H₂O precursor on the surface of graphene oxide, was synthesized by a solid-state process. The X-ray diffraction Rietveld refinement and Raman spectroscopy results indicated that multi-phase structural 2LiFePO₄·Li₃V₂(PO₄)₃ with a carbon/graphene coating was obtained. The morphology is characterized by HRTEM tests, which reveal well crystallized 2LFP·LVP@C/G with bridging graphene nanosheets, forming an effective three-dimensional conducting network. Compared with 2LiFePO₄·Li₃V₂(PO₄)₃@carbon (2LFP·LVP@C), the electrochemical results demonstrate that the 2LFP·LVP@C/G electrode measured at 0.1 C and 10 C can deliver a high specific discharge capacity of 151.2 mA h g⁻¹ and 125.4 mA h g⁻¹, respectively, and has a discharge capacity of 100.2 mA h g⁻¹ at −30 °C at 0.1 C, indicating better rate capability and thermal properties.