Low-temperature behavior of Li3V2(PO4)(3)/C as cathode material for lithium ion batteries

The electrochemical performance of Li3V2(PO4)(3)/C was investigated at various low temperatures in the electrolyte 1.0 mol dm(-3) LiPF6/ethyl carbonate (EC)+diethyl carbonate (DEC)+dimethyl carbonate (DMC) (volume ratio 1:1:1). The stable specific discharge capacity is 125.4, 122.6, 119.3, 116.6, 111.4, and 105.7 mAh g(-1) at 26, 10, 0, -10, -20, and -30 A degrees C, respectively, in the voltage range of 2.3-4.5 V at 0.2 C rate. When the temperature decreases from -30 to -40 A degrees C, there is a rapid decline in the capacity from 105.7 to 69.5 mAh g(-1), implying that there is a nonlinear relationship between the performance and temperature. With temperature decreasing, R (ct) (corresponding to charge transfer resistance) increases rapidly, D (the lithium ion diffusion coefficients) decreases sharply, and the performance of electrolyte degenerates obviously, illustrating that the low-temperature electrochemical performance of Li3V2(PO4)(3)/C is mainly limited by R (ct), D (Li), and electrolyte.