Positive Electrode Active Material And Method For Producing Same, And Non-Aqueous Electrolyte Secondary Battery Using Same

When a non-aqueous electrolyte secondary battery in which a positive electrode active material comprising a layered lithium-composite oxide is used for a positive electrode is subjected to charge/discharge under a prescribed condition, in a graph showing the relationship between voltage “V” with discharge during 5cycle and value dQ/dV from differentiation of battery capacity “Q” with discharge during 5cycle by voltage “V”, peak intensity ratio “r” represented by the equation: r=|Ic|/(|Ia|+|Ib|+|Ic|) satisfies 0