Effect of Zn, Cu and Mg doping on the structural characteristic of LiNi0.6Mn0.2Co0.2O2 (NMC622)

Abstract

LiNi0.6Mn0.2Co0.2O2 or NMC622 is a promising cathode material for Li-ion batteries. In this study, NMC622 was synthesized using batch oxalate co-precipitation followed by high temperature lithiation and sintering. Direct modification of NMC622 was employed via direct solid-state doping of Zn, Cu and Mg atoms at concentration of 0%, 1%, 3%, 5% and 10%. Doping source was obtained via simple and rapid precipitation. The doping was performed during LiOH mixing with NMC precursor. The doping source was pre-characterized using XRD analysis before the doping process. The final doped and un-doped NMC622 was analyzed structurally to study the optimum doping effect based on several structural parameters such as lattice parameters, lattice parameters ratio, cation mixing level, degree of hexagonal ordering and crystallite size.