Compared with the Li3 V2(PO4)3/C(LVP/C-S)prepared by sol-gel method,the Li3V2(PO4)3/C(LVP/C-R)composite cathode material prepared by hydrothermal ultrasonic-assisted rheological phase method combined with solution deposition method has better electrochemical performance.The synthesized materials were characterized by XRD,SEM and Raman spectroscopy.The synthesized materials were used as cathodes of lithium-ion batteries to assemble half-cells for rate and cycling performance tests,while the electrode reaction kinetics were analyzed by cyclic voltammetry,electrochemical impedance,and galvanosta-tic intermittent titration technique.The results show that the Li3V2(PO4)3(LVP-R)synthesized by hydro-thermal ultrasonic-assisted rheological phase method is coated with a carbon layer by solution deposition,leading to an increase in the crystal plane spacing,a smaller particle size,an increase in the electrical con-ductivity and tap density,and a significant enhancement in the dispersion.This facilitates the insertion/ex-traction of Li+in the cathode material and shortens the diffusion path of Li+,resulting in improved rate performance,coulombic efficiency and cycling stability of lithium-ion batteries.As the cathode material of lithium-ion batteries,LVP/C-R exhibits a high initial discharge specific capacity(160.12 mA·h/g)at a current density of 0.1 C,and the discharge capacity retention rate is 89.16％after 200 cycles at a current density of 1 C,which is much higher than that of LVP/C-S.In addition,LVP/C-R has a larger apparent Li+-diffusion coefficient and better kinetic performance in lithium-ion batteries compared to LVP/C-S and LVP-R.
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