摘要
以Li2CO3、Ni(CH3COO)2·2H2O、Mn(CH3COO)2·4H2O、Co(CH3COO)2·4H2O和Na2CO3为原料,通过直接沉淀法制备了具有α-NaFeO2型层状结构的微米Li1.52Ni0.30Mn0.78Co0.06O2.00正极材料.通过X射线衍射、扫描电镜、恒电流充放电、交流阻抗、循环伏安法等方法研究了样品的结构和电化学性能.结果表明:充电截止电压4.6V时样品的充放电性能最佳.在电流200 mAh·g-1时,该样品第1循环和第40循环的放电容量分别为150.2 mAh·g-1、155.0 mAh·g-1;样品的电化学反应受电荷传递阻抗和和Li+扩散的共同控制.
Rich-lithium manganese-based solid solution cathode material, Li1.52 Nio30 Mn0.78 Co0.06 O2.00, with a layered -NaFeO2 structure is synthesized by a direct precipitation method using LiE CO3, Ni（CH3COO） 2 2H2O, Mn（CH3COO）2 · 4H2O, Co（ CH3COO）2·4H20 and Na2CO3 as the starting materials. The samples are characterized by XRD, SEM, charge-discharge cycle, electrochemical impedance and cyclic vohammogram. Experimental results indicate that the samples show the best performance in the as-prepared samples when the charge cut-off potential is 4.6V. Li1.52 Ni0.30 Mn0.78 Co0.06 O2. oo exhibits the discharge capacities of 150.2 mAh·g^-1 in the 1st cycle and 155.0 mAh·g^-1 in the 40th cycle. Electrochemical reaction on the sample is controlled by the impedance of charge transfer and Li ＋ diffusion.
出处
《吉林化工学院学报》
CAS
2014年第1期89-94,共6页
Journal of Jilin Institute of Chemical Technology
基金
福建省科技厅重点项目(2010I0005)
科技部科技人员服务企业项目(2009GJC40003)
关键词
充电截止电压
富锂固溶体
正极材料
charge cut-off potential
rich-lithium solid state solution
cathode materials
