Effect of different MnO2 precursors on the electrochemical properties of spinel LiNi0.5Mn1.5O4 cathode active materials for high-voltage lithium ion batteries

LiNi0.5Mn1.5O4 (LNMO) cathode materials with different morphologies are prepared via a facile template method using various MnO2 precursors. The structures, morphologies and electrochemical properties of the as-prepared LiNi0.5Mn1.5O4 samples are tested by various physical and electrochemical methods. The results of characterization show that the spinel LNMO cathode materials have good crystal structure and the MnO2 precursors have no effect on the final products. Moreover, the specific morphology of LNMO is closely related to that of MnO2 precursor, and further influence the electrochemical performance. In addition, the LNMO sample using NH4HCO3 as precipitant exhibits excellent rate capability and cyclic stability in all as-prepared samples. Cycled at 0.5 and 1 C, the discharge capacities of LNMO cathode active particles using NH4HCO3 as precipitant are 110.6 and 102.2 after 200 charge-discharge cycles, respectively, which are the largest compared with the LNMO using (NH4)2S2O8 and KMnO4 as oxidants.