METHOD FOR REDUCING THE SURFACE AREA OF CARBONACEOUS POWDERS

摘要

The surface area of carbonaceous powders can be reduced by mixing a small amount of petroleum or coal tar pitch with the carbonaceous powder and pyrolyzing the mixture. The carbonaceous powder becomes coated with decomposition products of the pitch and the coating can have substantially lower surface area than the original carbonaceous powder. Small amounts of pyrolyzed pitch are involved and the bulk properties of the carbonaceous powder remain virtually unaffected. The method is particularly suitable for reducing the surface area of carbonaceous anode powders for use in non-aqueous rechargeable lithium ion batteries and thereby improves the safety of the batteries.