Non-aqueous secondary battery and a method of manufacturing graphite powder

摘要

A carbon material is provided having a superior reversibility in lithium intercalation-deintercalation reaction, and a non-aqueous secondary battery is provided which uses the carbon material as an active material for a negative electrode, which has a high energy density and an excellent rapid charging and discharging characteristics. Graphite powder having a maximum particle diameter of less than 100 mum and an existing fraction of rhombohedral structure in the crystalline structure of less than 20% is used as an active material for the negative electrode of the non-aqueous secondary battery. The graphite powder can be obtained by pulverizing raw graphite with a jet mill, and subsequently treating the powder at a temperature equal to or higher than 900° C.