Synthesis and electrochemical performance of xLi2MnO3•(1-x)LiMn0.5Ni0.4Co0.1O2 for lithium ion battery

The cathode material xLi(2)MnO(3)center dot(1 x)LiMn0.5Ni0.4Co0.1O2 was synthesized via a spray drying followed by solid-state calcination. The properties of the layered oxide cathodes for x=03, 0.5, 0.7 have been investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), galvanostatic cell cycling, as well as Ac impedance spectroscopy. The results indicate that, when x=0.3, the layered oxide cathode shows the best charge-discharge performances of low current density. Between 2.5 and 4.8 V (vs. Li/Li+), the initial discharge capacities of 0.3Li(2)MnO(3)center dot 0.7LiMn(0.5)Ni(0.4)Co(0.1)O(2) are 238, 229 and 206 mAhrg(-1) at a constant current density of 12.5, 25 and 50 mAg(-1), respectively. The electrode composition 0.7Li(2)MnO(3)center dot 0.3LiMn(0.5)Ni(0.4)Co(0.1)O(2) displays the best performance at high charge-discharge rate. The initial discharge capacity of 0.7Li(2)MnO(3)center dot 0.3LiMn(0.5)Ni(0.4)Co(0.1)O(2) is 135 mAhg(-1) at 250 mAg(-1), after 50 cycles, the discharge capacities of the layered oxide cathode remains 85%. (C) 2012 Elsevier B.V. All rights reserved.