铈掺钛酸锂负极材料的电化学性能研究

Study on Ce-doped Li_4Ti_5O_(12) Anode Materials for Lithium-ion Batteries

钛酸锂因循环性能好、安全,是目前较为理想的锂离子电池负极材料。采用溶胶-凝胶二步煅烧法制备Ce掺杂钛酸锂Li4Ti5-xCexO12(x=0,0.1,0.15,0.2),用SEM、XRD等物理表征手段和恒流充放电、交流阻抗等电化学方法表征材料性能,以考察铈掺杂量对材料电化学性能的影响。结果表明:x=0.15的样品粒径较小,在0.1C时比容量为168.0 mAh/g,1C时比容量为116.0mAh/g,倍率性能优于未掺杂的样品,1C下循环10次后容量仍保持在112.7mAh/g。

Ce-doped Li4 Ti5 O12 anode materials were prepared by two-step sol-gel reaction and the Ce-doped samples were characterized by SEM, XRD, charge-discharge process and electro- chemical impedance spectra in order to study the influence of Ce-doping on the material electro- chemical performance. The result shows, the doped sample with x=0. 15 had smaller size of a- bout 100~200 nm. The doped sample with x=0.15 ty of 168. 0 mAh/g at 0.1C and 116.0 mAh/g at 1C. remained at 112.7 mAh/g. shows better rate performance, with capaci- After 10 cycles at 1C, its discharge capacity