锂离子电池富锂正极材料Li[NixLi1/3-2x/3Mn2/3-x/3]O2(x=1/5, 1/4, 1/3)的合成及电化学性能

通过共沉淀法制备了M(OH)2(M=Mn, Ni)前驱体, 并与LiOH混合, 合成了锂离子电池富锂正极材料LiNixLi1/3-2x/3Mn2/3-x/3]O2, 采用XRD、SEM和充放电实验对其进行表征. 研究结果表明, Li, Ni, Mn原子在M层中呈有序分布, 形成超结构; 富锂正极材料由亚微米的一次粒子团聚组成1~3 μm颗粒; 在2.0~4.8 V电位范围内, 充放电电流密度为10 mA/g时, 富锂正极材料表现出很高的可逆比容量, 达到200~240 mA·h/g, 同时具有良好的循环可逆性能.

Synthesis and Electrochemical Behavior of Li-rich Cathode Materials Li[Ni_xLi_(1/3-2x/3)Mn_(2/3-x/3)]O_2(x=1/5,1/4,1/3) in the Lithium-ion Battery

The Li-rich cathode materials Li Ni_x Li_(1/3-2x/3) Mn _(2/3-x/3)] O_2 (x = 1/5, 1/4, 1/3 ) were synthesized with co-precipitated metal hydroxide precursors M ( OH ) _2 ( M = Mn, Ni ). The results of X-ray diffraction (XRD) and selected area electron diffraction(SAED) analysis confirmed the Li, Ni and Mn atoms are ordered in the M layer to form the superstrucutre. Images of scanning electron microscopy(SEM) show the Li-rich materials particles are about 1-3 μm, aggregated of submicron grains. Electrochemical behavior was examined by charge-discharge cycling. The LiNi_x Li_(1/3-2x/3)Mn_(2/3-x/3)] O_2 (x = 1/5, 1/4, 1/3 ) materials exhibited high reversible capacity of 200-240 mA·h/g and excellent cycle performance between 2.0 and 4.8 V at 10 mA/g current density.