Synthesis and Electrochemical Properties of Aluminum Doped Lithium Vanadium Phosphate

To improve the low conductivity of lithium vanadium phosphate,aluminum doped Li₃V₂(PO₄)₃/C powder was prepared by solution combustion synthesis using lithium nitrate,ammonium metavanadate and ammonium dihydrogen phosphate as raw materials,glycine as complexing agent and fuel,glucose as carbon source and aluminum nitrate as aluminum source,respectively.The electrochemical performances of the as-prepared aluminum doped Li₃V₂(PO₄)₃/C powder as cathode material for lithium ion battery were characterized by constant current charge-discharge,cyclic voltammetry(CV) and AC impedance(EIS).The results show that aluminum doping can effectively improve the conductivity of lithium vanadium phosphate.Different aluminum-doped proportions of lithium vanadium phosphate have different electron conductivities and diffusion rates of lithium ion.When the doping content of aluminum is 1%,the lithium vanadium phosphate has the optimum electrochemical performances with the discharge capacity of 104.6 mAh/g at the rate of 10 C after 500 cycles.