| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonaqueous electrolyte secondary battery excellent in a charge/discharge cycle characteristic by restraining an increase in internal impedance. SOLUTION: In a nonaqueous electrolyte secondary battery having a positive electrode part by applying a lithium including substance capable of reversibly storing/releasing lithium as a positive electrode active material, a graphite material included in the positive electrode part as a conductive agent is composed of a hexagonal system and a rhombic system, the peak area of a (101) diffraction line belonging to the rhombic system and the peak area of a (101) diffraction line belonging to the hexagonal system when measuring the graphite material by an X-ray wide angle diffraction method are respectively denoted by r(101) and h(101), and when a presence rate of the rhombic system included in the whole crystal of the graphite is shown by r(101)×12/15}/ r(101)×15/12+h(101)}, the presence rate of the rhombic system is 30% to 55%. |
