Anthracite-Derived Dual-Phase Carbon-Coated Li₃V₂(PO₄)₃as High-Performance Cathode Material for Lithium Ion Batteries

Abstract

In this study, low cost anthracite-derived dual-phase carbon-coated Li₃V₂(PO₄)₃ composites have been successfully prepared via a traditional solid-phase method. XRD results show that the as-prepared samples have high crystallinity and anthracite introduction has no influence on the LVP crystal structure. The LVP/C particles are uniformly covered with a dual-phase carbon layer composed of amorphous carbon and graphitic carbon. The effect of the amount of anthracite on the battery performance of LVP as a cathode material has also been studied. The LVP/C composite obtained with 10 wt % anthracite (LVP/C-10) delivers the highest initial charge/discharge capacities of 186.1/168.2 mAh g^-1 at 1 C and still retains the highest discharge capacity of 134.0 mAh g^-1 even after 100 cycles. LVP/C-10 also displays an outstanding average capacity of 140.8 mAh g^-1 at 5 C. The superior rate capability and cycling stability of LVP/C-10 is ascribed to the reduced particle size, decreased charge-transfer resistance, and improved lithium ion diffusion coefficient. Our results demonstrate that using anthracite as a carbon source opens up a new strategy for larger-scale synthesis of LVP and other electrode materials with poor electronic conductivity for lithium ion batteries.