The present invention provides a high-capacity and low-cost non-aqueous
electrolyte secondary battery, comprising: a negative electrode
containing, as a negative electrode active material, a substance capable
of absorbing/desorbing lithium ions and/or metal lithium; a separator; a
positive electrode; and an electrolyte, wherein the positive electrode
active material contained in the positive electrode is composed of
crystalline particles of an oxide containing two kinds of transition
metal elements, the crystalline particles having a layered crystal
structure, and oxygen atoms constituting the oxide forming a cubic
closest packing structure.