MODIFIED NATURAL GRAPHITE PARTICLE AND METHOD FOR PRODUCING SAME

摘要

Modified natural graphite particles intended for forming a negative electrode material for a nonaqueous electrolyte secondary battery are characterized by having a circularity of at least 0.93 and at most 1.0 and a surface roughness of at most 1.5% with respect to the length of the particles. These modified natural graphite particles are obtained by a manufacturing method including a step of applying an impact force to natural graphite particles for pulverization and spheroidization to obtain intermediate particles having a circularity of at least 0.93 and at most 1.0, and a step of carrying out surface smoothing of the resulting intermediate particles by mechanical grinding treatment to obtain the modified natural graphite particles.