多元掺杂尖晶石型Li_(1.02)M_xMn_(2-x)Q_yO_(4-y)正极材料的电化学特性

作     者：唐致远 卢星河 张娜 TANG Zhi-Yuan;LU Xing-He;ZHANG Na

作者机构：天津大学化工学院天津300072 

出 版 物：《无机化学学报》 (Chinese Journal of Inorganic Chemistry)

年 卷 期：2005年第21卷第9期

页      面：1427-1432页

核心收录：

学科分类：081704[工学-应用化学] 08[工学] 0817[工学-化学工程与技术] 

基　　金：国家自然科学基金(No.20273047) 教育部博士点基金(No.20020056045)资助项目 

主　　题：锂离子电池 多元复合掺杂 正极材料 电化学性能 

摘      要：The effect of doping on the electrochemical performance was studied for spinel type Li1.02MxMn2-xQyO4-y used as cathode material in lithium-ion battery. TG/DTA curves of the precursor (the raw materials) doped with different elements were studied. The spinel materials Li1.02Mn2O4, Li1.02Co0.02Cr0.01La0.01Mn1.96F0.02O3.98, Li1.02Co0.02Cr0.01 La0.01Mn1.96Cl0.02O3.98, Li1.02Co0.02La1.02Mn1.97Cl0.02O3.98, Li1.02Co0.02Cr0.01Mn1.97O4, were prepared by solid-state reaction method after the pretreatment of conversion under low temperature and uniform mixing. X-ray diffraction patterns showed that all the samples had perfect spinel structure. SEM indicated that the particles of the samples had uni- form size and were distributed evenly. The results of the charge/discharge curves showed that Li1.02Co0.02Cr0.01La0.01Mn1.96F0.02O3.98 had better performance than other materials according to the inhibition of decline of reversible capacity of spinel Li1.02MxMn2-xQyO4-y. Therefore, cycle performance had been improved so obviously that 93.9% of the initial capacity were preserved after 100 cycles. Furthermore, electrochemical impedance tests were carried out with the spinel Li1.02Co0.02Cr0.01La0.01Mn1.96F0.02O3.98 as working electrode, Lithium as counter elec- trode and reference electrode. Results showed that this material possessed good charge/discharge reversible capa- bility and had the lowest impedance in 3.95￣4.25 V range (on the stage of charge / discharge).