NOVELTY - Nonaqueous electrolyte secondary battery has positive electrode containing lithium-nickel complex oxide, negative electrode containing lithium-titanium complex oxide and lithium-containing phosphorus oxide, and nonaqueous electrolyte. Ratio (b/a) of lithium occlusion capacity (b) during initial discharging of lithium-nickel complex oxide and lithium discharge capacity (a) during initial charging of lithium-nickel complex oxide is 75-90. The mass ( gamma ) of lithium-containing phosphorus oxide and mass ( beta ) of lithium-titanium complex oxide satisfy a specified relation (I).    USE - Nonaqueous electrolyte secondary battery is used for battery pack for motor vehicles (both claimed) e.g. hybrid vehicles. Can also be used for electronic devices.    ADVANTAGE - The nonaqueous electrolyte secondary battery has high safety and energy density.    DETAILED DESCRIPTION - Nonaqueous electrolyte secondary battery has a positive electrode containing lithium-nickel complex oxide, a negative electrode containing lithium-titanium complex oxide and lithium-containing phosphorus oxide, and nonaqueous electrolyte. The ratio (b/a) of lithium occlusion capacity (b) during initial discharging of lithium-nickel complex oxide with respect to lithium discharge capacity (a) during initial charging of lithium-nickel complex oxide is 75-90. The ratio (y/x) of lithium discharge capacity (y) during initial discharging of lithium-titanium complex oxide with respect to lithium occlusion capacity (x) during initial charging of lithium-titanium complex oxide is 90-100. The lithium occlusion capacity (x) during initial charging of lithium-titanium complex oxide is less than that of the lithium occlusion capacity (z) of lithium-containing phosphorus oxide. The ratio of lithium occlusion capacity during initial discharging of lithium-nickel complex oxide with respect to lithium discharge capacity during initial charging of lithium-nickel complex oxide is less than that of the ratio of lithium discharge capacity during initial discharge of lithium-titanium complex oxide with respect to lithium occlusion capacity during initial charging of lithium-titanium complex oxide. The mass ( gamma ) of lithium-containing phosphorus oxide and mass ( beta ) of lithium-titanium complex oxide satisfy relation: 0 less than (( gamma )/( beta )) less than or equal to (ay-bx)/bz (I).    DESCRIPTION OF DRAWING(S) - The drawing shows side view of nonaqueous electrolyte secondary battery.    Rectangular-shaped cladding material (11)    Rectangular cover (12)    Winding electrode (13)    Negative electrode terminal (20)    Negative electrode gasket (21)