Abstract We synthesized LiNi0.5Mn1.5O4 cathode materials by using ammonia-mediated carbonate precipitation, and we studied how the ammonia concentration during synthesis (0.1-0.5 mol/L) affected the structural, physicochemical, and electrochemical characteristics of the prepared materials. X-ray diffraction and Rietveld refinement reveal that the amount of Li/Ni antisite defects in the LiNi0.5Mn1.5O4 depend much on the ammonia concentration. The LiNi0.5Mn1.5O4 prepared at 0.3 mol/L has the fewest Li/Ni antisite defects. This sample also delivers the best electrochemical performance, retaining a capacity of 133.5 mAh g-1 after 20 cycles at 0.1 C. Electrochemical impedance spectroscopy confirms that the LiNi0.5Mn1.5O4 prepared at 0.3 mol/L has lower charge transfer resistance, correlating with its better ion diffusion kinetics than the other materials.
Gu, Y. J., Li, Y., Fu, Y., Zang, Q. F., Liu, H. Q., Ding, J. X., … Ni, J. (2015). LiNi0.5Mn1.5O4 synthesized through ammonia-mediated carbonate precipitation. Electrochimica Acta, 176, 1029–1035. https://doi.org/10.1016/j.electacta.2015.07.114