Patent ID: 6929885

Claim:
A non-aqueous electrolytic secondary battery comprising: a casing comprising a sheet with a thickness of 0.5 mm or less which has a resin layer, an electrode group having: a positive electrode, a negative electrode which contains a material capable of storing and releasing lithium ions, and a separator disposed between the positive electrode and the negative electrode; and a non-aqueous electrolytic solution containing at least one non-aqueous solvent and at least one lithium salt dissolved in said solvent which impregnates said electrode group; at least 50% of the total volume of the non-aqueous solvent is γ-butyrolactone, at least 10% of the total volume of the non-aqueous solvent is ethylene carbonate, and wherein the non-aqueous solvent contains 0.01 to 5% by weight of at least one vinylene carbonate compound represented by the formula (I), 0.01 to 5% by weight of at least one vinylethylene carbonate compound represented by the formula (II), and the total amount of the vinylene carbonate compound and the vinylethylene carbonate compound is 0.02 to 6% by weight; wherein formulas (I) and (II) are: wherein R 1 and R 2 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, wherein R 3 , R 4 and R 5 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R 6 , R 7 and R 8 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or an alkenyl group having 2 to 7 carbon atoms.