Objects of the present invention is to provide a carbon material having a
superior reversibility in lithium intercalation-deintercalation reaction,
and a non-aqueous secondary battery using 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 .mu.m 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.degree. C.