NONAQUEOUS SECONDARY BATTERY AND MANUFACTURE OF GRAPHITE POWDER

摘要

PURPOSE: To provide a carbon material excellent in reversibility of lithium storing-releasing reaction, and a nonaqueous secondary battery which uses this as a negative electrode material and has high energy density and is excellent in a quick charging-discharging characteristic. CONSTITUTION: A nonaqueous secondary battery is constituted by using graphite powder, on which a particle diameter is not more than 100μm and a rate of a rhombohedral structure existing in a crystal structure is not more than 20%, as a negative electrode active material. Such graphite powder is obtained by performing heat treatment on graphite at a temperature not less than 900 degrees C after it is pulverized by a jet mill.