Composite positive electrode active material for lithium ion battery, preparing method thereof, an

The present invention relates to a composite positive electrode active material for a lithium ion battery which contains a nickel-rich lithium nickel-based compound having a nickel content of 50 to 100 mol% based on the total amount of transition metals, and a coating film comprising rare earth metal hydroxide formed on the surface of the nickel-rich lithium nickel-based compound; a preparing method thereof; and a lithium ion battery including a positive electrode comprising the composite positive electrode active material.COPYRIGHT KIPO 2018