Li4Ti5O12/Sn composite anodes for lithium-ion batteries: Synthesis and electrochemical performance

Li4Ti5O12/tin phase composites are successfully prepared by cellulose-assisted combustion synthesis of Li4Ti5O12 matrix and precipitation of the tin phase. The effect of firing temperature on the particulate morphologies, particle size, specific surface area and electrochemical performance of Li4Ti5O12/tin oxide composites is systematically investigated by SEM, XRD, TG, BET and charge–discharge characterizations. The grain growth of tin phase is suppressed by forming composite with Li4Ti5O12 at a calcination of 500 °C, due to the steric effect of Li4Ti5O12 and chemical interaction between Li4Ti5O12 and tin oxide. The experimental results indicate that Li4Ti5O12/tin phase composite fired at 500 °C has the best electrochemical performance. A capacity of 224 mAh g−1 is maintained after 50 cycles at 100 mA g−1 current density, which is still higher than 195 mAh g−1 for the pure Li4Ti5O12 after the same charge/discharge cycles. It suggests Li4Ti5O12/tin phase composite may be a potential anode of lithium-ion batteries through optimizing the synthesis process.