Lithium secondary battery with easy state of charge estimation

A positive electrode for a lithium secondary battery, the positive electrode comprising:

• a positive electrode current collector;
• and
• n positive electrode mixture layers disposed on the positive electrode current collector, wherein n is an integer of 2 or more,
• wherein a first positive electrode mixture layer contacting a surface of the positive electrode current collector contains a first positive electrode active material comprising an iron phosphate compound represented by Formula 1 and a second positive electrode active material comprising a lithium composite metal oxide represented by Formula 2,
• wherein second to nth positive electrode mixture layers disposed on the first positive electrode mixture layer comprise the first positive electrode active material containing the iron phosphate compound represented by Formula 1.
• LiFeaM11-aXO4 [Formula 1]
• Lix[NiyCozMnwM2v]O2 [Formula 2]
• wherein in Formula 1 and Formula 2,
• M1 is one or more elements selected from the group consisting of W, Cu, Fe, V, Cr, Co, Ni, Mn, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo,
• X is one or more elements selected from the group consisting of P, Si, S, As, and Sb, a is 0≤a≤0.5,
• M2 is one or more elements selected from the group consisting of W, Cu, Fe, V, Cr, Ti, Zr, Zn, Al, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Nb, Mg, B, and Mo, and
• x, y, z, w, and v are 1.0≤x≤1.30, 0.1≤y≤1, 0≤z≤1, 0≤w≤1, 0≤v≤0.1, respectively, where y+z+w+v=1.