| abstract |
(57) [Summary] [Problems] To prevent carbonization from a mesophase powder obtained from coal tar or the like, without performing surface oxidation treatment for preventing fusion, carbonize, and further graphitize. , Manufacture graphite powder for negative electrode of lithium ion secondary battery. SOLUTION: In the carbonization step, the temperature is raised in a temperature range of at least 300 to 700 ° C. in an inert gas atmosphere at a pressure of 1.01 to 5 atm, preferably at a temperature rising rate of 100 ° C./hr or less. Do not do. |