LiOH.H2O,V2O5 and Y(NO3)3 were used as raw materials to synthesize the precursors containing Li,V and Y by liquid-state reaction,then the cathode materials Li1.05YxV3-xO8(x=0,0.002 5,0.005,0.01,0.02,0.1,0.2)for lithium-ion battery were obtained by calcining the precursors.The influence of Y3 +doping on structure,conductivity and electrochemical performance of Li1.05V3O8 were investigated by using XRD,cyclic voltammograms,AC impedance,etc.The results show that Li1.05YxV3-xO8 with different doping amounts have well-developed crystal structure of layered Li1.05V3O8 and lengthened interlayer distance of(100) crystal plane.Y3 + can insert into crystal lattice completely when the doping amount is small and the impurity phase of YVO4 is found when x≥0.1.There is no change in the process of Li+insertion-deinsertion with Y 3+doping.The conductivity is clearly improved due to small amount of Y 3+ doping and it tends to increase first and then decrease with increasing doping amount.The initial discharge capacity and plateau potential are both enhanced with proper amount of Y3 +doping.When x is 0.005,the first specific discharge capacity reaches 288.9 mA.h/g,4.60%larger than that of undoped sample(276.2 mA.h/g).When x≤0.1,the average discharge plateau potentials are enhanced by about 0.15 V,which makes for higher energy density.
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