Precursor of transition metal compound, lithium transition compound using the same, positive active material including the lithium transition compound and lithium ion secondary battery including the positive active material

PURPOSE: A transition metal compound precursor, a lithium transition metal compound using thereof, and a lithium ion secondary battery are provided to minimize the generation of electrode degeneration, and to improve the lifetime property and the rate property of the lithium ion secondary battery. CONSTITUTION: A transition metal compound precursor contains 3-5% of large particle size transition metal compound precursors and 65-75% of small particle size transition metal compound precursors. The tap density of the transition metal compound precursor is greater than 2.2g/cc. The particle size of the large particle size transition metal compound precursors is 6-20 micrometers. The particle size of the small particle size transition metal compound precursors is 1-8 micrometers.