The high capacity and excellent rate capability of Ti-doped Li2MnSiO4 as a cathode material for Li-ion batteries
Abstract
Ti-doped Li2Mn1−xTixSiO4 as cathode materials for Li-ion batteries was successfully synthesized by a facile sol–gel method. The addition of Ti to the precursors changed the particle sizes and specific surface areas of Li2MnSiO4. The galvanostatic charge–discharge measurements showed that Ti-doped Li2Mn1−xTixSiO4 (x = 0.06, 0.1, 0.2) electrodes delivered high charge capacity of 298, 286, 248 mA h g−1 and discharge capacity of 203, 211, 171 mA h g−1 in the first cycle, much higher than that of undoped Li2MnSiO4 (52 mA h g−1 for charging and 26 mA h g−1 for discharging). Moreover, the Ti-doped samples exhibited good cycling stability and superior rate capability, as compared to that of pristine sample. Even at a high rate (2 C), the Ti-doped Li2Mn1−xTixSiO4 still maintained high discharge capacities. The remarkable enhancement of battery performance in terms of capacity and rate capability for doped Li2Mn1−xTixSiO4 was primarily attributed to the decrease of charge transfer resistance and the improvement of the Li+ diffusion coefficient.