Li4Ti5O12/(Cu+C) composite as anode material for lithium-ion batteries was synthesized by chemical deposition combined with thermal decomposition of a mixture of Cu(CH3COO)2·H20, C6H12O6 and Li4Ti5O12. The structure, morphology and electrochemical performance of samples were characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), galvanostatic charge-discharge test, cyclic voltammeter (CV) and electrochemical impedance spectroscopy (ELS). The results showed that surface coating of Cu and C on Li4Ti5O12 particle improved its electronic conductivity and therefore enhanced the performance of the circulation and rate capability. The discharge capacity of the composite were 168.2, 160 and 140.6 mAh·g-1 at 0.5C, lC and 3C rate after 50 cycles, and the corresponding capacity retention were 88.7％, 84.4％ and 71.2％, respectively. ElS test proved that surface coating of Cu and C on Li4Ti5O12 particle could decrease its charge transfer resistance greatly.%以Li4Ti5O12,Cu(CH3COO)2·H2O和C6H12O6为前驱体,化学沉积与热分解结合合成锂离子电池负极材料Li4Ti5O12/(Cu+C).采用X-射线衍射(XRD)、扫描电子显微镜(SEM)、恒流充放电、循环伏安和电化学阻抗方法表征样品的结构、形貌和电化学性能.结果表明,Li4Ti5O12表面包覆的Cu与C提高了Li4Ti5O12电极材料的导电率,其循环性能和倍率性能得到有效地改善.在0.5C、1C和3C倍率下,经过50次充放电循环,放电比容量分别为168.2、160、140.6 mAh·g-1,其容量保持率分别为88.7%、84.4%、71.2%.电化学阻抗测试表明,表面包覆的Cu与C使其电荷转移阻抗大幅度减少.
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