COMPOSITE CATHODE ACTIVE MATERIAL FOR LITHIUM ION BATTERY, MANUFACTURING METHOD THEREFOR, AND LITH

Disclosed are : a composite cathode active material for a lithium ion battery comprising a coating film, the composite cathode active material comprising a nickel-rich lithium nickel-based compound having a nickel content of 50-100 mol% on the basis of the total amount of transition metals, and a rare earth metal hydroxide formed on the surface of the nickel-rich lithium nickel-based compound; a manufacturing method therefor; and a lithium ion battery containing a cathode comprising the same.