以蔗糖为碳源,采用固相法合成了C改性的Li4Ti5O12材料.XRD衍射分析表明,C的引入没有改变Li4Ti5O12的尖晶石结构,且缓解了颗粒间的团聚,并以初始蔗糖含量为10%(by mass)样品的电化学性能最佳.0.2C放电倍率下首次放电比容量达179.1 mAh/g,在2C和3C倍率下首次放电比容量仍达143.8 mAh/g和129.4 mAh/g.循环伏安和电化学阻抗测试显示改性后的Li4Ti5O12材料电极极化程度较小,并且具有较小的电极反应阻抗.
The carbon modified Li4Ti5O12 was prepared by solid state reaction by using sucrose as carbon source.The XRD results showed that the incorporation of carbon did not change the spinel crystal structure of Li4Ti5O12 but it could prevent the particle agglomeration.The sample with 10%(by mass) sucrose displayed the best electrical performance,a 179.1 mAh/g of initial specific capacity was obtained at 0.2C,while 143.8 and 129.4 mAh/g at 2C and 3C,respectively.The CV and EIS studies revealed that carbon modification lowered the electrode polarization and electrode reaction resistance of Li4Ti5O12.
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