LITHIUM SECONDARY BATTERY NEGATIVE ELECTRODE MATERIAL AND MANUFACTURE THEREOF

摘要

PURPOSE:To provide a lithium secondary battery negative electrode material with high charge/discharge efficiency and high discharge capacity further with high cycle stability against charge/discharge repetition. CONSTITUTION:A lithium secondary battery negative electrode material is carbon fiber powder formed by crushing pitch carbon fiber to provide a 0.338nm or less intercarbon layer distance (d) and a 5 to 200mum mean grain size. Pitch fiber is burned at 800 to 2600 deg.C to prepare carbon fiber thereafter crushed, and by again baking the obtained crushed carbon fiber at a baking temperature or higher before its crushing, the carbon fiber powder having the above- mentioned graphite degree and mean grain size is manufactured, to manufacture the lithium secondary battery negative electrode material. In this way, a battery of high cycle stability against charge/discharge repetition is obtained.