| 摘要 |
PROBLEM TO BE SOLVED: To obtain graphite particles suitable for negative electrode material of lithium secondary battery excellent in quick charge and discharge characteristics, cycle characteristic, irreversible volume, etc., in first cycle and excellent in safety. SOLUTION: The graphite particles are obtained by collecting and binding a plurality of flat particles so that orientation surface becomes nonparallel. The graphite particles have 0-0.15 strength ratio (P1 /P2 ) of diffraction line having rhombohedral structure (P2 : 43.2 deg. angle of diffraction) to diffraction line having hexagonal crystal structure (P2 : 44.3 deg. angle of diffraction) in wide angle X-ray diffraction diagram using CuKα line. This method for producing graphite particles comprises adding graphitized catalyst to aggregate capable of graphitizing or a binder capable of graphitizing with the graphite and mixing, baking and pulverizing these components and further subjecting the resultant particles to heat treatment at >=400 deg.C in non-oxidizing atmosphere. This lithium battery is obtained by using graphite particles obtained by the above producing method as a negative electrode material 2. |
