Grafted and crosslinked carbon black as an electrode material for double layer capacitors

Isocyanate prepolymers can readily react with oxidic functional groups on carbon black. Different prepolymers were examined for their grafting behaviour. In carbon black grafted with di-isocyanates, reactive isocyanate groups are available for cross-linking to a polyurethane system. This crosslinked carbon black was designed as a new active material for electrochemical electrodes. The successful crosslinking of carbon black was demonstrated by determinations of the grafted groups via titration and via thermogravimetric analysis. Products of this type were tested as an active material for electric double layer capacitor application. Active material for electric double layer capacitor electrodes was produced which had a specific capacitance of up to 200 F/g. Crosslinking efficiencies of up to 58% of the utilized polymers were achieved. (C) 2002 Elsevier Science Ltd. All rights reserved.