Electrochemical Performance Ni Doped Spinel LiMn2O4 Cathode for Lithium Ion Batteries
LiNixMn2-xO4 (x=0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5) compounds with spinel crystal structure are synthesized by sol-gel method. The dependence of the physicochemical properties of these compounds has been extensively investigated by using X-ray diffraction (XRD), scanning electron microscope (SEM), cyclic voltammogram (CV) and charge-discharge test. It is found that as Mn is replaced by Ni, the initial capacity decreases, but the capacity retention is enhanced. Of all the LiNixMn2-xO4 (x=0, 0.05, 0.1, 0.2, 0.3, 0.4) compounds, the LiNi0.2Mn1.8O4 has best electrochemical performance, about 120mAhg-1 discharge capacity, its capacity retention rate of 96.6% after 100 cycles. However the LiNi0.5Mn1.5O4 sample shows excellent electrochemical performance at 4.7 V high potential, 150 mAhg-1 discharge capacity, above 110 mAhg-1 of capacity retention after 42 cycles of charge/discharge. The prepared LiNi0.5Mn1.5O4 powders sintered at 750 °C here has Fd3m space group.
Weiguo Pan, Jianxing Ren and Yongguang Li
Y. L. Cui et al., "Electrochemical Performance Ni Doped Spinel LiMn2O4 Cathode for Lithium Ion Batteries", Advanced Materials Research, Vols. 347-353, pp. 290-300, 2012