| abstract |
The invention provides a positive electrode active material, a positive electrode material, a positive electrode and a non-aqueous electrolyte secondary battery, in particular a means capable of suppressing capacity decline during long-term use and improving cycle characteristics in the non-aqueous electrolyte secondary battery. The positive electrode active material for the non-aqueous electrolyte secondary battery is lithium-nickel-manganese-cobalt composite oxide with a true density of 4.40-4.80 g/cm 3 . |