NOVELTY - A nonaqueous electrolyte secondary battery (1) has isolation film (4) provided between positive electrode plate (2) and negative electrode plate (3), negative electrode lead (9) and positive electrode lead (11), and contains non-aqueous electrolyte which consists of supporting electrolyte dissolved in nonaqueous solvent. The negative electrode lead connects negative electrode plate and terminal portion of negative electrode. The positive electrode lead connects positive electrode plate and terminal portion of positive electrode.    USE - Nonaqueous electrolyte secondary battery is used as power supply for electronic device e.g. mobile telephone and notebook personal computer and power tool such as electric driver and electric vehicle.    ADVANTAGE - The nonaqueous electrolyte secondary battery has reduced short circuit during large current discharge, and high capacitance.    DETAILED DESCRIPTION - A nonaqueous electrolyte secondary battery has isolation film provided between positive electrode plate and negative electrode plate, negative electrode lead and positive electrode lead, and contains non-aqueous electrolyte which consists of supporting electrolyte dissolved in nonaqueous solvent. The negative electrode lead connects negative electrode plate and terminal portion of negative electrode. The positive electrode lead connects positive electrode plate and terminal portion of positive electrode. The positive electrode plate contains active material. The negative electrode plate contains active material. The positive electrode active material contains lithium-containing complex oxide of formula: LixNiyCozM1-y-zO2, where M is chosen from magnesium, barium, aluminum, titanium, strontium, calcium, vanadium, iron, copper, bismuth, yttrium, zirconium, molybdenum, technetium, ruthenium, tantalum, rhenium and/or tungsten, x is 0.9-1.2, y is 0.3-0.9, z is 0.05-0.5 and 1-y-z is 0.01-0.3. The concentration of supporting electrolyte is 0.6-1.6 mol/l. The ratio of product of concentration (mol/L) of supporting electrolyte and dimensional volume (mm3) of nonaqueous electrolyte secondary battery, and cross-sectional area (mm2) of negative electrode lead, is 11000-56000.    DESCRIPTION OF DRAWING(S) - The drawing shows sectional view of the nonaqueous electrolyte secondary battery.    Battery (1)    Positive electrode plate (2)    Negative electrode plate (3)    Isolation film (4)    Negative electrode lead (9)    Positive electrode lead (11)