NOVELTY - A nonaqueous electrolyte secondary battery (10) comprises negative electrode (2) containing graphite particles as negative electrode active material, positive electrode (1) containing lithium-containing oxide of transition metal or lithium-containing phosphate of transition metal as positive electrode active material, and nonaqueous electrolyte solution (3) which is obtained by dissolving lithium salt in organic solvent. The nonaqueous electrolyte solution contains phosphate ester compound (I) to which alkynyl group is bonded, and/or unsaturated phosphate ester compound (II).    USE - Nonaqueous electrolyte secondary battery e.g. coin-shaped nonaqueous electrolyte secondary battery. Uses include but are not limited to video camera, digital camera, sound recorder, portable music player, notebook personal computer, mobile telephone, portable television, hybrid vehicle, electric power-assisted bicycle, portable digital versatile disc player, etc.    ADVANTAGE - The nonaqueous electrolyte secondary battery has improved output and capacity, reduced internal resistance and high electric capacitance.    DETAILED DESCRIPTION - A nonaqueous electrolyte secondary battery comprises negative electrode containing graphite particles as negative electrode active material, positive electrode containing lithium-containing oxide of transition metal or lithium-containing phosphate of transition metal as positive electrode active material, and nonaqueous electrolyte solution which is obtained by dissolving lithium salt in organic solvent. The graphite particles have exposed crystal face, and are bonded with each other so as to be parallel to orientation plane of each other. The nonaqueous electrolyte solution contains phosphate ester compound of formula: (HCC-C(-R1)-R2-O)2-P(=O)-O-R3 (I) to which alkynyl group is bonded, and/or unsaturated phosphate ester compound of formula: (R6-O)2-P(=O)-O-C(-R4)(-R5)-(CC)n-C(-R4)(-R5)-O-P(=O)-(O-R6)2 (II).    R1,R2,R4,R5=H or 1-8C alkyl;    R3,R6=1-8C alkyl, 2-8C alkenyl, 2-8C alkynyl or 1-8C haloalkyl;and    n=1 or 2.    DESCRIPTION OF DRAWING(S) - The drawing shows a longitudinal cross-sectional view of the coin-shaped nonaqueous electrolyte secondary battery.    Positive electrode (1)    Positive electrode collector (1a)    Negative electrode (2)    Negative electrode collector (2a)    Nonaqueous electrolyte solution (3)    Coin-shaped nonaqueous electrolyte secondary battery (10)