Disclosed is a carbonaceous material for anodes of lithium ion rechargeable batteries. The carbonaceous material consists of soot particles which are prepared from liquified propane gas through thermal decomposition. The soot particles are of disordered or amorphous carbon with very small crystallite sizes (La, Lc≦30 Å), containing a large quantity of unorganized carbon. When being used as an active material for an anode of a lithium ion secondary cell, the soot shows far greater reversible capacity than do conventional graphite carbonaceous materials.