This technology involves a primary heat treatment of transition metal hydroxides in an ammonia atmosphere to create nanostructured metal nitride intermediates. These are then mixed with a lithium source and subjected to a secondary heat treatment, which promotes single-crystal formation of grains within the primary particles and reduces internal strain to 0.088, thereby enhancing electrical conductivity and charge-discharge efficiency.
Conventional cathode active materials, such as LiCoO2, have faced issues with structural instability during manufacturing and shortened lifespans due to repeated charge-discharge cycles. In particular, they were limited by non-uniform grains within primary particles and residual strain, which hindered electrical conductivity.
This technology synthesizes nanostructured metal nitride intermediates with a specific surface area more than nine times larger by heat-treating transition metal hydroxide precursors in a 400°C ammonia atmosphere. These are then mixed with a lithium source and calcined in an oxygen atmosphere to produce primary particles with a high single-crystal ratio. Applicable to high-voltage lithium cobalt oxide-based mobile device batteries and mass production processes for nickel-manganese layered cathodes, this method improves particle crystallinity simply by modifying the heat treatment path, without the need for additional doping.
This invention was developed with support from the Ministry of Science and ICT for research on the correlation between the physical properties of atomic-level controlled metal nanoclusters and their photoelectrochemical behavior.
N/A
