Patent ID: 7217475

Claim:
A non-aqueous electrolyte secondary battery provided with a positive electrode, a negative electrode, a separator interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte, wherein positive electrode active material in said positive electrode is a mixture of lithium-manganese composite oxide having spinel structure represented by a general formula Li 1+z Mn 2 O 4 wherein 0<z<0.2 is satisfied, and lithium-transition metal composite oxide represented by the general formula LiNi 1−x−y Co x Mn y O 2 wherein 0.5<x+y<1.0 and 0.1<y<0.6 are satisfied; and negative electrode active material in said negative electrode is graphite coated with low crystalline carbon where whole or a part of a surface of first graphite material as a substrate is coated with second carbon material which is lower in crystallinity compared with the first graphite material.