Fibres made from different nanostructured carbons (carbon black (CB)), carbon nanotubes (CNT) and CB/CNT were successfully developed by wet-spinning. The variation of dispersion conditions (carbon nanomaterial concentration, dispersant/Carbon nanomaterial concentration ratio, CB/CNT concentration ratio, pH) resulted in different electrochemical performance for each type of fibres. Fibres with the best capacitance values (10 F g(-1)) and good cycling stability (89%) were obtained from fibres containing 10% carbon black and 90% carbon nanotubes. A solid-state supercapacitor was fabricated by assembling the CB/CNT fibres resulting in 9.2 F g(-1) electrode capacitance. Incorporation of 0.2 wt% birnessite-type potassium manganese oxide nanotubes dramatically increased the capacitance of the fibres up to 246 F g(-1) due to the high specific capacitance of birnessite phase and the tubular nature of the nanomaterial. (C) 2018 Elsevier Ltd. All rights reserved.