Patent ID: 7879489

Claim:
A non-aqueous electrolyte secondary battery comprising: a positive electrode comprising a nickel-containing lithium composite oxide as a positive electrode active material; a negative electrode capable of charging and discharging; a separator interposed between said positive electrode and said negative electrode; and a non-aqueous electrolyte comprising a non-aqueous solvent and a solute dissolved in said non-aqueous solvent, wherein said non-aqueous electrolyte contains fluorobenzene and vinyl ethylene carbonate, and said nickel-containing lithium composite oxide is represented by a general formula (1): LiNi x M 1-x-y L y O 2 , where element M is at least one selected from the group consisting of Co and Mn; element L is at least one selected from the group consisting of Al, Sr, Y, Zr, Ta, Mg, Ti, Zn, B, Ca, Cr, Si, Ga, Sn, P, V, Sb, Nb, Mo, W and Fe; and x and y satisfy 0.7≦x≦0.9 and 0≦y<0.1, respectively.