POSITIVE ELECTRODE ACTIVE MATERIAL FOR USE IN LITHIUM SECONDARY BATTERY AND LITHIUM SECONDARY BATTERY USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a positive electrode active material for use in a lithium secondary battery that can produce the lithium secondary battery having high discharge capacity and superior cycle performance, and to provide the lithium secondary battery having high discharge capacity and superior cycle performance. SOLUTION: This positive electrode active material for use in the lithium secondary battery contains a Li-Mn-Ni composite oxide characterized in that a mean diameter of primary particles of the Li-Mn-Ni composite oxide is 2.0 μm or less and N2 -BET specific surface area is 0.4 m<2> /g or more. Then, the positive electrode active material for use in the lithium secondary battery contains a Li-Mn-Ni-Co composite oxide characterized in that a mean diameter of primary particles of the Li-Mn-Ni-Co composite oxide is 3.0 μm or less and N2 -BET specific surface area is 0.2 m<2> /g or more.