Patent ID: 8470475

Claim:
A non-aqueous electrolyte secondary battery comprising: a positive electrode capable of absorbing and desorbing lithium; a negative electrode capable of absorbing and desorbing lithium; a separator interposed between said positive electrode and said negative electrode; and a non-aqueous electrolyte, wherein said positive electrode comprises a composite oxide represented by formula (1): LiNi x M 1-x-y L y O 2 as an active material, where said formula (1) satisfies 0.3≦x≦0.9 and 0<y<0.1, element M is at least one selected from the group consisting of Co and Mn, and element L comprises at least one of Mg, Al, Ti, and Sr, and said non-aqueous electrolyte comprises a main solvent, a solute, and vinyl ethylene carbonate, and vinylene carbonate.