Microwave synthesis of spherical Li[Ni0.4Co0.2Mn0.4]O2 powders as a positive electrode material for lithium batteries

Microwave-irradiation-assisted synthesis using hydroxides was used to prepare lithiated transition metal oxide within a short time for lithium batteries. Li[Ni 0.4Co0.2Mn0.4 ]02 powders were prepared by synthesizing spherical [Ni0.4Co0.2Mn 0.4](OH)2 via coprecipitation. Spherical secondary particles seem to be closely piled acicular primary particles in the scanning electron microscopy (SEM) image. Repetitive microwave treatments also led to a single-phase product, though the crystallinity of the resulting product was quite poor compared with that of the material produced by conventional solid-state reaction. Homogeneous hydroxide enabled an one-step, single-phase formation of the well-developed highly crystalline oxide by means of microwave irradiation, which significantly reduces the reaction time and cost.