Positive electrode for secondary battery and secondary battery including the same

A positive electrode for a secondary battery comprising:

• a positive electrode current collector, and
• a positive electrode active material layer disposed on at least one surface of the positive electrode current collector, the positive electrode active material layer comprising:
• a lower layer disposed on the surface of the positive electrode current collector, and
• an upper layer disposed on a top of the lower layer, the upper layer comprising:
• a first positive electrode active material,
• a first conductive material, and
• a first binder resin,
• the lower layer comprising:
• a second positive electrode active material,
• a sacrificial positive electrode material,
• a second conductive material, and
• a second binder resin, and
• each of the first positive electrode active material and the second positive electrode active material independently comprises at least one compound represented by Chemical Formula 1;
• LiNi1−xMxO2 [Chemical Formula 1]
• wherein M includes at least one of Mn, Co, Al, Cu, Fe, Mg, B, and Ga, and x is 0-0.5,
• wherein the sacrificial positive electrode material is absent from the upper layer, and
• wherein the sacrificial positive electrode material in the lower layer comprises at least one compound represented by Chemical Formula 2:
• Li6Co1−xZnxO4 [Chemical Formula 2]
• wherein x is 0-1.