The invention discloses a preparation method of large-particle-size and high-density spherical
cobalt oxide. The preparation method aims at achieving the purposes that the median particle size D50 of the
cobalt oxide is larger than or equal to 15 microns,
particle size distribution is uniform, compacting density (TD) is larger than or equal to 2.2 g / cm<3>, and the large-particle-size and high-density spherical
cobalt oxide can meet the development requirement of high-
voltage lithium cobaltate. The preparation method of the
cobalt oxide includes the cobalt
carbonate synthesis stage and the spherical cobalt
carbonate thermal decomposition stage. In the cobalt
carbonate synthesis stage, a cobalt carbonate precursor prepared through many times of cyclic
crystallization is compact and uniform in
particle size distribution; due to the segmented
thermal decomposition, cobalt carbonate is locally decomposed in the low-temperature pre-decomposing stage, a micro hole channel is formed, release of CO2 gas during subsequent
decomposition is facilitated, and particles are prevented from
crazing or being broken; in the high-temperature
thermal decomposition stage, the particle surface is compact, and therefore the large-particle-size and high-density spherical
cobalt oxide is prepared.