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通过LiNO3与Mn(NO3)2的混合溶液与LiNi1/3Co1/3Mn1/3O2粉体共混干燥后在900℃热处理12 h制备了xLi2MnO3.(1-x)LiNi1/3Co1/3Mn1/3O2(x=0.1、0.2、0.3和0.4)固溶体。随着x的增加,固溶体的XRD峰强度减弱,峰形变宽,而在20°~30°间的结构特征峰(LiMn6)更加明显;尽管固溶体的外观形貌为团聚状,但组成其的单颗粒平均粒径随着x增大,由x=0.1时的250 nm增大到x=0.4时的350 nm。随着充放电截止电压的升高,固溶体的放电比容量增大;在2.5~4.6 V间充放电,当x=0.2时,充放电的极化最小,放电平台最高;不同倍率充放电循环21周后发现随着x的增大,容量保持率从91.2%增加大105.6%。研究结果表明,Li2MnO3可以改善LiNi1/3Co1/3Mn1/3O2材料的电化学性能。
XLi2MnO3. (1-x) LiNi1 / 3Co1 / 3Mn1 / 3O2 (x = 1) was prepared by blending LiNO3 and Mn (NO3) 2 with LiNi1 / 3Co1 / 3Mn1 / 3O2 powders and then heat- 0.1, 0.2, 0.3 and 0.4) solid solution. With the increase of x, the XRD peak intensity of the solid solution is weakened and the peak shape is widened, while the structural characteristic peak (LiMn6) between 20 ° and 30 ° is more obvious. Although the appearance morphology of the solid solution is aggregated, The average particle size increases with x increasing from 250 nm at x = 0.1 to 350 nm at x = 0.4. With the increase of the cut-off voltage, the specific capacitance of the solid solution increases. When charged and discharged between 2.5 and 4.6 V, the charge and discharge polarizations are the minimum and the discharge platform is the highest when x = 0.2. It was found after week that with the increase of x, the capacity retention rate increased by 105.6% from 91.2%. The results show that Li2MnO3 can improve the electrochemical performance of LiNi1 / 3Co1 / 3Mn1 / 3O2 materials.