A positive electrode with a positive electrode current collector and a positive electrode mixture layer, and the positive electrode mixture layer has first and second positive electrode mixture layers. The first positive electrode mixture layer comprises a positive electrode active material composed of compound A that contains Ni, Co, Al and Li. The second positive electrode mixture layer is disposed between the first positive electrode mixture layer and the positive electrode current collector, and comprises a positive electrode active material including: said compound A; and a Li-containing compound B which is smaller in specific capacity (mAh/g) and average particle diameter than said compound A. In said compound A, a ratio of Ni to the total number of moles of the metal elements except Li is 82 mol % or more. The average particle diameter of said compound B is 55% or less of the average particle diameter of said compound A.