Negative electrode material for nonaqueous secondary cells, negative electrode for nonaqueous secondary cells, and nonaqueous secondary cell

Abstract

A negative electrode material for a nonaqueous secondary battery capable of realizing a nonaqueous secondary battery having a small charging/discharging irreversible capacity at an initial cycle and exhibiting an excellent high-rate charging/discharging characteristics and an excellent cycle performances is provided. The main component of the material is graphite particles. The median diameter is 5 μm or more, and 40 μm or less in the volume-basis particle size distribution based on the laser diffraction/scattering particle size distribution measurement. The tapping density is 0.7 g/cmor more. The specific surface area measured by a BET method is 0.2 m/g or more, and 8 m/g or less. The average circularity is 0.83 or more, and 1.00 or less. When an electrode is produced by a predetermined method for manufacturing an electrode and, the resulting electrode is subjected to X-ray diffraction, the graphite crystal orientation ratio I/Ion the electrode is 0.08 or more, where Irepresents the wide angle X-ray diffraction peak area of the (110) peak peak in the region of 2θ=76.5 to 78.5 degrees of the graphite particles on the electrode and Irepresents the wide angle X-ray diffraction peak area of the (004) peak peak in the region of 2θ=53.5 to 56 degrees.