A positive electrode comprising: a positive electrode material layer comprising a positive electrode active material consisting of a compound of a first positive electrode active material which has a composition represented by a formula described below and a second positive electrode active material which is represented by Li a CoM h O 2, with 0 < a ≤ 1.2, and 0 ≤ h ≤ 0.1, and wherein M is at least one element selected from the group consisting of Al, Cr, Mg and Fe, and the positive electrode material layer satisfying a formula described below; and a positive electrode current collector on which the positive electrode material layer is formed; Li x Ni 1-a-b Co a M b O 2 wherein M is at least one element selected from the group consisting of Mg, Al, Mn, Si, Ti, Zn, Zr, Ca and Sn; x, a and b satisfy 0.9<x≤1.25, 0<a≤0.4, and 0≤b≤0.45; 35 [m 2 /cm 3] ≤ S1/V1 ≤ 70 [m 2 /cm 3] wherein S1 is a pore specific surface area, expressed in m 2 /g, of the positive electrode material layer, obtained by a pore distribution measurement according to a mercury porosimetry, and V1 is a pore volume, expressed in cm 3 /g, obtained by the pore distribution measurement, and the first positive electrode active material has a mode diameter in a range of 1 μm to 10 μm in a pore distribution obtained by the mercury porosimetry; and the maximum pore volume lies in a range of 0.005 cm 3 /g to 0.1 cm 3 /g for the range of pore diameters of 0.01 to 0.5 μm in the pore distribution, wherein the mode diameter is a diameter of a pore at the maximum pore volume in a pore distribution curve, wherein the positive electrode active material comprises independent primary particles and secondary particles, wherein the positive electrode material layer further comprises an electron conductive substance and a binder, and wherein a ratio of the positive electrode active material is from 73 to 95% by weight, a ratio of the electron conductive substance is from 3 to 20% by weight, and a ratio of the binder is from 2 to 7% by weight. a positive electrode material layer comprising a positive electrode active material consisting of a compound of a first positive electrode active material which has a composition represented by a formula described below and a second positive electrode active material which is represented by Li a CoM h O 2, with 0 < a ≤ 1.2, and 0 ≤ h ≤ 0.1, and wherein M is at least one element selected from the group consisting of Al, Cr, Mg and Fe, and the positive electrode material layer satisfying a formula described below; and a positive electrode current collector on which the positive electrode material layer is formed; Li x Ni 1-a-b Co a M b O 2 wherein M is at least one element selected from the group consisting of Mg, Al, Mn, Si, Ti, Zn, Zr, Ca and Sn; x, a and b satisfy 0.9<x≤1.25, 0<a≤0.4, and 0≤b≤0.45; 35 [m 2 /cm 3] ≤ S1/V1 ≤ 70 [m 2 /cm 3] wherein S1 is a pore specific surface area, expressed in m 2 /g, of the positive electrode material layer, obtained by a pore distribution measurement according to a mercury porosimetry, and V1 is a pore volume, expressed in cm 3 /g, obtained by the pore distribution measurement, and the first positive electrode active material has a mode diameter in a range of 1 μm to 10 μm in a pore distribution obtained by the mercury porosimetry; and the maximum pore volume lies in a range of 0.005 cm 3 /g to 0.1 cm 3 /g for the range of pore diameters of 0.01 to 0.5 μm in the pore distribution, wherein S1 is a pore specific surface area, expressed in m 2 /g, of the positive electrode material layer, obtained by a pore distribution measurement according to a mercury porosimetry, and V1 is a pore volume, expressed in cm 3 /g, obtained by the pore distribution measurement, and the first positive electrode active material has a mode diameter in a range of 1 μm to 10 μm in a pore distribution obtained by the mercury porosimetry; and the maximum pore volume lies in a range of 0.005 cm 3 /g to 0.1 cm 3 /g for the range of pore diameters of 0.01 to 0.5 μm in the pore distribution, wherein the mode diameter is a diameter of a pore at the maximum pore volume in a pore distribution curve, wherein the positive electrode active material comprises independent primary particles and secondary particles, wherein the positive electrode material layer further comprises an electron conductive substance and a binder, and wherein a ratio of the positive electrode active material is from 73 to 95% by weight, a ratio of the electron conductive substance is from 3 to 20% by weight, and a ratio of the binder is from 2 to 7% by weight.