摘要
用溶胶凝胶法制备了Li Ni1/3Co1/3-x Mn1/3Znx O2(x=0,1/24,2/24,4/24)锂离子电池正极材料。由X射线衍射和扫描电镜对其分析结果表明,Zn掺杂不改变Li Ni1/3Co1/3Mn1/3O2的α-Na Fe O2层状结构,当掺杂量达到4/24时,杂相产生。电化学研究表明,当Zn掺杂量为2/24时,Li Ni1/3Co1/3Mn1/3O2首次放电容量由未掺杂的169.2 m Ah·g-1降低为160.1m Ah·g-1,但循环性能明显提高,30次循环后的容量保持率由未掺杂的89.2%升至97%。并且在20、40、60和80 m A·g-1不同的电流密度下继续循环20次后,当再次恢复到20 m A·g-1的电流密度时,放电容量可恢复到150.3 m Ah·g-1。
Li Ni1/3Co1/3-x Mn1/3Znx O2（x=0, 1/24, 2/24 and 4/24） cathode material for lithium-ion battery was synthesized by a sol-gel method.The results of XRD and SEM show that Zn doping does not change the α-Na Fe O2 layer structure of Li Ni1/3Co1/3Mn1/3O2, and impurity phases occur when the doped amount reaches 4/24. Electrochemical studies indicate that when the doped Zn content is 2/24, the initial discharge capacity of Li Ni1/3Co1/3Mn1/3O2 decreases from 169.2 m Ah·g-1 of the undoped material to 160.1 m Ah·g^-1. The cycling performance, however, is significantly improved. Compared with undoped material, the capacity retention rate of the sample of Li Nil/3Col/3-x Mnl/3Znx O2 with x=2/24 increases from 89.2% to 97% after 30 cycles. The same sample was charged and discharged again at20 m A·g-1 and the corresponding discharge specific capacity was restored to 150.3 m Ah·g-1 after 20 cycles in different current densities of20, 40, 60 and 80 m A·g^-1.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2015年第3期743-747,共5页
Rare Metal Materials and Engineering
基金
国家自然科学基金(51102174)
