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  

Electrochemistry Performance for the Multiple Doping Spinel Type Li_(1.02)M_xMn_(2-x)Q_yO_(4-y)

作　　者：唐致远[1] 卢星河 张娜[1] 

机构地区：[1]天津大学化工学院,天津300072

出　　处：《无机化学学报》2005年第9期1427-1432,共6页Chinese Journal of Inorganic Chemistry

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

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).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 uniform 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 electrode and reference electrode. Results showed that this material possessed good charge/discharge reversible capability and had the lowest impedance in 3.95～4.25 V range （on the stage of charge / discharge）.

关 键 词：锂离子电池 多元复合掺杂 正极材料 电化学性能 

分 类 号：O646[理学—物理化学]