Positive electrode having lithium transition metal oxide containing nickel, cobalt and manganese for secondary battery and secondary battery including the same

A positive electrode for a secondary battery, comprising:

• a positive electrode active material layer which comprises:
• a positive electrode active material including a lithium transition metal oxide which contains nickel, cobalt, and manganese and having an atomic ratio of nickel in total transition metals of 80 atm % or more;
• and
• a metal oxide including a metallic element having a binding potential with lithium of 0.5 V to 4 V,
• wherein the metal oxide is included in an amount of 0.1 wt % to 2 wt % based on a total weight of the positive electrode active material layer, and
• wherein the lithium transition metal oxide has a concentration gradient in which at least one element of the nickel, the cobalt, or the manganese in the lithium transition metal oxide is continuously changed across an entire particle or in a specific region.