锂离子电池负极材料Li3．9Mn0．1Ti5O12／C的性能研究

文章采用固相法合成了电化学性能优异的碳包覆的锂离子电池负极材料Li3．9Mn0．1Ti5O12／C，并对材料进行了XRD、激光粒度分析、循环伏安测试及恒电流充放电测试。结果表明：Mn的掺杂未改变材料的晶体结构，由于Mn4＋对Li4Ti5O12的晶胞内部的掺杂和C对其晶胞外部的包覆，使复合材料的电导率，大电流循环稳定性和可逆比容量都明显提高。在1C充放电循环时，Li3．9Mn0．1Ti5O12／C首次放电容量为162．4mAh／g，50次循环后，稳定在159．6mAh／g，容量保持率为98．3％；在2C充放电循环时，首次放电容量达到了153．5mAh／g，展示了优良的电化学特性。

Studies of Cathode Li3.9 Mn0.1 Ti5 O12/C Materials for Lithium--ion Batteries

Li3.9 Mn0.1 Ti5 O12/C as cathode material for lithium--ion batteries was synthesized by solid-- state method. The morphology and microstructure of the samples were characterized by XRD analysis. The electrochemical properties were investigated. It was shown that the Mn4＋ doped Li4Ti5 O12 keeps the spinel structure of the Li4Ti5012, while the conductivity, capacity and cycle stability of Li4 Ti5 O12 was enhanced by Mn4＋ inner crystalloids and the carbon outer crystal particles. The first discharge capacity of Li3.9 Mn0.1 Ti5 O12/C was 162.4mAh/g with a current density 1C, and after 50 cycles the capacity was still 159.6mAh/ g. A relative capacity of 98.3% was obtainable. The first discharge capacity was 153.5mAh/g at 2C. Li3.9 Mn0.1Ti5 O12/C shows very excellent electrochemical performance.