GRAPHITE MATERIAL FOR NEGATIVE POLE OF LITHIUM SECONDARY BATTERY, METHOD OF MANUFACTURING THE GRAPHITE MATERIAL, AND LITHIUM SECONDARY BATTERY

摘要

This invention relates to a graphite material for negative electrode of lithium secondary battery. This graphite material is obtained by carbonizing the pulverized green coke to yield coke, adding one kind or more of boron or a compound thereof to the coke, graphitizing the resulting mixture and controlling the particle size of the product graphite. This graphite material for negative electrode is characterized by showing a tap density of 0.95 g/cm<3> or more after tapping 20 times or 1.15 g/cm<3> or more after tapping 300 times and a BET specific surface area of 1.5 m<2>/g or less. A lithium secondary battery made by the use of this graphite material for negative electrode has a large discharge capacity and suffers little loss during charging and discharging.