Li4Ti5O12@C复合材料的制备及其性质研究

Preparation and Electrochemical Performance of Li4Ti5O12@C Anode Material

摘要:

本文以葡萄糖为碳源，采用原位复合法制备锂离子电池复合负极材料Li4Ti5O12@C，同时探讨了不同碳包覆量对Li4Ti5O12的影响。通过X-射线衍射和扫描电子显微镜对合成出的材料结构及表面形貌进行表征，采用恒电流充放电和电化学阻抗等技术对其进行电化学性能测试。结果表明：碳包覆量为3 %的Li4Ti5O12颗粒均匀且电化学性能最好。在0.5 C下，首次放电比容量为185.9 mAh/g，循环50次后，其放电比容量仍为161.5 mAh/g。在2.0 C下，首次放电比容量为99.9 mAh/g，材料表现出优良的电化学性能。

Abstract:

In this paper, Li4Ti5O12@C was prepared by in-situ composite method using glucose as carbon source. The effect of different carbon content on Li4Ti5O12 was investigated. The structure and surface morphology of the composites were characterized by X-ray diffraction and scanning electron microscopy. The electrochemical performance was measured by constant current charge-discharge and electrochemical impedance spectroscopy. The results show that Li4Ti5O12 coated with 3 % carbon is homogeneous and has the best electrochemical performance. Its first discharge capacity is 185.9 mAh/g, and remains 161.5 mAh/g after 50 cycles at the charge and discharge rate of 0.5 C. Its first discharge capacity is 99.9 mAh/g, when disharged at 2.0 C.