NON-AQUEOUS ELECTROLYTE SECONDARY BATTERY

A non-aqueous electrolyte secondary battery that is one aspect of the present disclosure is provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte, the positive electrode having a positive electrode current collector and a positive electrode mixture layer that contains a positive electrode active material and that is formed on the surface of the positive electrode current collector, the positive electrode active material including a lithium-containing composite oxide represented by a prescribed general formula, the lithium-containing composite oxide having secondary particles formed by aggregation of primary particles, Ca being present on the surfaces and in the interiors of the secondary particles, and the proportion of Ca present on the surfaces of the secondary particles being 12-58% relative to the total amount of Ca present on the surfaces and in the interiors of the secondary particles.