The intercalation/deintercalation kinetic studies on the structure-integrated cathode material 0.5Li2MnO3 0.5LiNi0.5Mn0.5O2

A cathode material, 0.5Li(2)MnO(3) 0.5LiNi(0.5)Mn(0.5)O(2), was prepared by citric acid-assisted sol-gel method and its electrochemical performance was investigated. It delivered a charge capacity of 270 mAh g(-1) and a discharge capacity of 189 mAh g(-1) in the first cycle. With the increase of current density from 14 to 28 mA g(-1), the discharge capacity dropped severely to 130 mA g(-1). Obviously, the rate capability of the material was inferior to most of the oxide cathode materials. The diffusion coefficient of this material was calculated to be 6.04 x 10(-12) cm(2) s(-1) from the results of cyclic voltammetry measurements. Moreover, diffusion coefficients between 3.13 x 10(-12) and 1.22 x 10(-10) cm(2) s(-1) in the voltage range of 3.8-4.7 V were obtained by capacity intermittent titration technique. This, together with the localized Li2MnO3 domains in the crystal structure, may validate the poor rate capability.