摘要
为了研究钛酸钠锂(Na2Li2Ti6O14)负极材料嵌脱锂的动力学行为,用溶胶-凝胶法合成Na2Li2Ti6O14负极材料,采用X射线衍射法(XRD)和电子显微镜(SEM)分别对材料进行物相分析和微观形貌的观察。采用恒流充放电测试、循环伏安法(CV)和恒电流间歇滴定法(GITT)研究了Na2Li2Ti6O14的电化学性能和嵌脱锂过程动力学。研究结果表明,制备的Na2Li2Ti6O14材料纯度高,结晶度良好,循环稳定性好;由不同扫描速率的循环伏安法测出的Na2Li2Ti6O14中锂离子在氧化、还原峰对应的化学扩散系数Da和Dc分别为7.3×10-11和7.8×10-11 cm2/s;由恒电流间歇滴定技术测得的锂离子在Na2Li2Ti6O14电极中的扩散系数为10-11～10-8 cm2/s。
In order to investigate the electrochemical kinetics of Li-ion in Na2Li2Ti6O14 materials for lithium ion bat- teries. Na2Li2Ti6O14 anode materials have been synthesized by sol-gel method in this work. The sample was characterized by X-ray diffraction（XRD）and scanning electron microscope（SEM）. The electrochemical performance and kinetics of Na2Li2Ti6O14 were investigated by galvanostatic charge-discharge test, cyclic voltammetry（CV） and galvanostatic intermittent titration technique（GITT）. The results show that the pure and crystallized Na2Li2Ti6O14 delivers good cycle performance. The D. and D0 of diffusion coefficients of Li-ion in Na2Li2Ti6O14 are 7. 3×10^-11/s and 7.8×10^-11cm^2/s in oxidation and reduction peaks respectively by CV, and the diffusion coefficients of Liion in Na2Li2Tie O14 are in the range of 10-11-10-8 cm2/s by GITT method.
出处
《桂林电子科技大学学报》
2012年第3期249-253,共5页
Journal of Guilin University of Electronic Technology
基金
广西教育厅科研项目(201101ZD007)
