Herein, we demonstrate a structure-enabled strategy to construct an ultrastable, high-performance, ultraflexible all-in-one supercapacitor with a one-piece wood cellulose network/polyaniline/multiwalled carbon nanotube composite as both the electrodes and the separator. A cellulose network was used as the carrier and separator, and multiwalled carbon nanotube and polyaniline acted as conducting materials. Excellent flexibility was achieved by combining the cellulose network with a polyvinyl alcohol-based electrolyte. Natural directional channel...