Microstructure of Li(Mn1/3Ni1/3Co1/3)O2 cathode material for lithium ion battery: Dependence of crystal structure on calcination and heat-treatment temperature

Cathode compounds of composition Li(Mn1/3Ni1/3Co1/3)O2 have been prepared by calcination of the precursor materials at 700, 800, 900 and 1000 °C for 24 h and by subsequent heat-treatments at 1100 °C for 4–6 h. It has been observed that the structural ordering and particle size increase with increasing calcination temperature. The compounds calcined at 700 °C and 800 °C are not well-crystallized, but the distribution of particles is uniform. However, the compounds calcined at 900 °C and 1000 °C are well-crystallized with a non-uniform distribution of particles. The compounds calcined at 900 °C are well-crystallized with a well-ordered hexagonal structure. The samples calcined at 800 °C and heat treated at 1100 °C for 4 h also show same structure. They have smooth surface morphology with uniform distribution of particles in the sub-micron (0.15–0.40 μm) range and less amount of cation mixing.