Ultrafast charge and discharge biscrolled yarn supercapacitors for textiles and microdevices

Flexible, wearable, implantable and easily reconfigurable supercapacitors delivering high energy and power densities are needed for electronic devices. Here we demonstrate weavable, sewable, knottable and braidable yarns that function as high performance electrodes of redox supercapacitors. A novel technology, gradient biscrolling, provides fastion-transport yarn in which hundreds of layers of conducting-polymer-infiltrated carbon nanotube sheet are scrolled into similar to 20 mu m diameter yarn. Plying the biscrolled yarn with a metal wire current collector increases power generation capabilities. The volumetric capacitance is high (up to similar to 179 Fcm(-3)) and the discharge current of the plied yarn supercapacitor linearly increases with voltage scan rate up to similar to 80 Vs(-1) and similar to 20 Vs(-1) for liquid and solid electrolytes, respectively. The exceptionally high energy and power densities for the complete supercapacitor, and high cycle life that little depends on winding or sewing (92%, 99% after 10,000 cycles, respectively) are important for the applications in electronic textiles.We thank J.P. Ferraris for valuable discussions. This work was supported by Creative Research Initiative Center for Bio-Artificial Muscle of the Ministry of Education, Science and Technology (MEST) and the MEST-US Air Force Cooperation Program (Grant No.2012-00074) in Korea; Air Force Grant AOARD-10-4067, Air Force Office of Scientific Research grant FA9550-12-1-0211, and Robert A. Welch Foundation grant AT-0029 in the United States; and the Australian Research Council through the Centre of Excellence and Fellowship program