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 Li ₄Ti₅O₁₂ 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 Li ₄Ti₅O₁₂/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 Li ₄Ti₅O₁₂ 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 Li₄Ti₅O ₁₂/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 Li₄Ti₅O ₁₂ after the same charge/discharge cycles. It suggests Li ₄Ti₅O₁₂/tin phase composite may be a potential anode of lithium-ion batteries through optimizing the synthesis process.