In this paper, two carbon-coated lithium titanate (LTO-C1 and LTO-C2) composites were synthesized using the ball-milling-assisted calcination method with different carbon precursor addition processes. The physical and electrochemical properties of the as-synthesized negative electrode materials were characterized to investigate the effects of two carbon-coated LTO synthesis processes on the electrochemical performance of LTO. The results show that the LTO-C2 synthesized by using Li₂CO₃ and TiO₂ as the raw materials and sucrose as the carbon source in a one-pot method has less polarization during lithium insertion and extraction, minimal charge transfer impedance value and the best electrochemical performance among all samples. At the current density of 300 mA·h·g⁻¹, the LTO-C2 composite delivers a charge capacity of 126.9 mA·h·g⁻¹, and the reversible capacity after 300 cycles exceeds 121.3 mA·h·g⁻¹ in the voltage range of 1.0–3.0 V. Furthermore, the electrochemical impedance spectra show that LTO-C2 has higher electronic conductivity and lithium diffusion coefficient, which indicates the advantages in electrode kinetics over LTO and LTO-C1. The results clarify the best electrochemical properties of the carbon-coated LTO-C2 composite prepared by the one-pot method.

本文采用球磨辅助煅烧方法，采用不同的碳前驱体添加工艺，合成了两种碳包覆的钛酸锂（LTO-C1和LTO-C2）复合材料。表征了合成后负极材料的物理和电化学性能，以研究两种碳包覆的LTO合成工艺对LTO电化学性能的影响。结果表明，Li ₂ CO ₃和TiO ₂合成LTO-C2一锅法中作为原料使用蔗糖作为碳源，而在锂的插入和萃取过程中使用蔗糖作为碳源，则在所有样品中具有较小的极化，最小的电荷转移阻抗值和最佳的电化学性能。在300 mA·h·g ^-1的电流密度下，LTO-C2复合材料的充电容量为126.9 mA·h·g ^-1，在300次循环后的可逆容量超过121.3 mA·h·g ^-1在1.0–3.0 V的电压范围内。此外，电化学阻抗谱显示LTO-C2具有更高的电子电导率和锂扩散系数，这表明电极动力学优于LTO和LTO-C1。结果阐明了通过一锅法制备的碳包覆的LTO-C2复合材料的最佳电化学性能。