柠檬酸包覆钛酸锂负极材料的改性研究

采用柠檬酸(C6H8O7·H2O)作碳源制备Li4Ti5O12/C复合材料,利用X射线粉末衍射仪(XRD)和扫描电子显微镜(SEM)研究了柠檬酸添加量对材料结构和形貌的影响。研究结果表明:添加不同量的柠檬酸,所制备的样品均为尖晶石型结构。随着柠檬酸添加量的增加,材料颗粒粒径逐渐增大,分布更加均匀,团聚也逐渐加剧。在1.0~2.5V的电压范围内,对样品进行恒流充放电测试,柠檬酸(C6H8O7·H2O)的添加量为6%时,制备的Li4Ti5O12/C复合材料具有最佳的电化学性能,0.2C和1C的放电比容量分别为171.3m Ah/g和165.4m Ah/g。

Modification of Lithium Titanate Oxide Anode Material with Coating Citric Acid

Li4Ti5O12/C composite materials were synthesized using citric acid as carbon source. The crystal structure and morphology of Li4Ti5O12/C composite materials with different amount of citric acid were analyzed by powder X-ray diffraction （XRD） and scanning electron microscope （SEM）. With the content of citric acid raised, particle size increased gradually and dispersed more uniformly,thus it led to more agglomeration. The electrochemical characteristics of the Li4Ti5O12/C composite materials were examined by galvanostatic charge-discharge instrument with a cut-off voltages of 1.0~2.5 V. The results show that the discharge specific capacity of Li4Ti5O12/C composite material coated with 6% citric acid are 171.3mAh/g and 165.4mAh/g at 0.2 C and 1C rate, respectively.