Synthesis and electrochemical performance of Li4Ti5O12/C composite by a starch sol assisted method
Synthesis and electrochemical performance of Li4Ti5O12/C composite by a starch sol assisted method
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DOI：
10.1016/j.powtec.2011.09.011
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发表时间：
2012
影响因子：
5.2
通讯作者：
Li Wang;Zonglin Zhang;Guangchuan Liang;Xiuqin Ou;Ying Xu
中科院分区：
文献类型：
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作者：
Li Wang;Zonglin Zhang;Guangchuan Liang;Xiuqin Ou;Ying Xu
以锐钛矿型二氧化钛和碳酸锂为原料，以可溶性淀粉为碳源，采用简单的淀粉溶胶辅助法制备了Li4Ti5O12/C复合负极材料。系统研究了焙烧温度和淀粉量对其微观结构和电化学性能的影响。用X射线衍射仪、扫描电子显微镜、透射电子显微镜和恒流充放电循环测试对样品进行了表征。结果表明，添加10wt.%淀粉的Li4Ti5O12/C复合材料在800℃下反应6h，粒径分布均匀，平均粒径为200~300 nm，在0.2℃、1℃、2℃和5℃倍率下的放电比容量分别为168.5、160.8、155.1和141.8mAhg−1，循环稳定性较好。这可能是由于均匀的超细粒子和原位碳涂层增强了锂离子在电极中的电子电导和扩散。
Li4Ti5O12/C composite anode materials were synthesized by a simple starch sol assisted method using TiO2-anatase and Li2CO3as raw materials and soluble starch as carbon source. The influences of calcination temperature and starch amounts on the microstructure and electrochemical performance were systematically investigated. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and constant-current charge/discharge cycling tests. The results showed that the Li4Ti5O12/C composite with 10wt.% starch synthesized at 800°C for 6h had homogeneous particle size distribution with an average particle size of 200–300nm and exhibited the optimal electrochemical performance with specific discharge capacities of 168.5, 160.8, 155.1 and 141.8mAh g−1at 0.2°C, 1°C, 2°C and 5°C rates, respectively, and satisfactory cycling stability. It could be attributed to the homogeneous ultrafine particles and in situ carbon coating, which enhanced the electronic conductivity and diffusion of lithium ions in the electrode.