| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a highly graphitized carbon material with high characteristics as a material for a lithium secondary battery negative electrode by industrial scale heat treatment using an acheson furnace or an LWG furnace. SOLUTION: This material is powder obtained by heating raw carbon powder in an air-existing atmosphere together with boron or a boron compound, and graphitizing the carbon powder, having a d002 of the graphite crystal <=0.337 nm, the content of boron nitride on the surface is reduced, and the content of boron oxide calculated in terms of B2O3 is 0.3 wt.%. After heat treating, at least one treatment of pulverizing, crushing, and grinding is conducted, followed by washing to manufacture the powder. Or after treating, washing is conducted followed by crushing to manufacture the powder. Washing with water containing a surfactant is preferable. The material with high performance is stably manufactured at low cost. |
