| abstract |
(57) [Summary] [PROBLEMS] To provide a non-aqueous electrolyte secondary battery in which battery performance is less deteriorated even when stored at a high temperature. SOLUTION: In the lithium-containing composite oxide, 50 Å By using, as a cathode active material, a pore having a pore volume of 0.003 cm 3 or less per gram of lithium-containing composite oxide having a pore radius of not more than a positive electrode active material due to decomposition of an electrolytic solution during storage at high temperature Reduces material coverage and suppresses battery performance degradation. |