Application of Kenaf-derived Carbon as Conductive Electrode Additive in Electric Double-layer Capacitors

Biochar produced from bio-waste of cellulose-extracted kenaf residue was utilized as a conductive additive for electrodes in electric double-layer capacitors (EDLCs). The EDLC cells were assembled using electrodes with varying mixing ratios of kenaf-derived carbon (KC), and hydrocarbons-derived carbon black (CB) which had been industrially utilized as the conductive additive. Although the sole use of KC could not provide a sufficient electronic conduction in the EDLC electrodes, the combinational use of KC and CB attained a formation of stable conductive path therein. The energy density of the EDLC cell utilizing electrodes composed of KC and CB at a mixing ratio of 50:50 in mass under the use of 8 M KOH electrolytic solution and the cell voltage range of 0−1.0 V was found to be approximately equivalent to that of electrodes composed solely of CB, particularly at power densities below 100 W kg−1. Through the application of KC to the conductive electrode additive, we discovered new potential uses for kenaf residue.