High electrochemical performance of lithium-rich Li1.2Mn0.54NixCoyO2 cathode materials for lithium-ion batteries.

Li 1.2 Mn 0.54 Ni x Co y O 2 (x+y=0.26, and x:y=1:1, 1:2, 2:1, 1:3, 3:1) was synthesized by aerogel with urea as chelating agent. The physical and electrochemical properties of the cathode materials were investigated through X-ray diffraction, scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy analyses as well as and charge/discharge tests. Results showed that samples with different Ni/Co ratios crystallized well and showed a layered structure. The sample, Li 1.2 Mn 0.54 Ni 0.195 Co 0.065 O 2 (x:y=3:1), delivered a high discharge capacity of 313 mA h g −1 at 20 mA g −1 and exhibited excellent cycle performance after 50 cycles, with a capacity of 247 mA h g −1 at 100 mA g −1 . [ABSTRACT FROM AUTHOR]