Synthesis of Spherical and Dense Particles of the Pure Hydroxide Phase Ni[sub 1∕3]Mn[sub 1∕3]Co[sub 1∕3](OH)[sub 2]

The structure of the coprecipitated precursor to the positive electrode material, (NMC), is typically synthesized via a coprecipitation reaction and assumed to be or . The coprecipitation reaction and its products are not thoroughly understood. Here, pure phase is synthesized in the presence of aqueous ammonia, yielding dense and spherical particles. was found to readily oxidize in air, especially during heating. The obtained product was analyzed with powder X-ray diffraction and thermogravimetric analysis. The results indicate that undergoes oxidation to the oxyhydroxide phase, . Heating also resulted in an increase in tap density of the oxyhydroxide; the final tap density of the material was found to be .