HIGH-CAPACITY POSITIVE ELECTRODE ACTIVE MATERIAL WITH IMPROVED CONDUCTIVITY AND NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY COMPRISING SAME

摘要

The present invention relates to a positive electrode active material comprising lithium manganese oxide, wherein the lithium manganese oxide has spinels, and shows a phase transition phenomenon of a core-shell, in which the crystal structure of the spinels is phase-transited from a cubic structure to a tetragonal structure from a surface to a center of a particle during a process of discharging to a 3V region. The shell portion contains a conductive material for improving the electrical conductivity of the tetragonal structure.