the claimed invention uses activated carbon fibers that incorporate porous carbon with a suitable pore size to maximize capacitance . the porous carbon material is prepared using a template , followed by incorporation into a matrix polymer and electrospinning of the mixture . subsequent thermal treatments retain the fiber form , and a composite carbon fiber incorporating templated porous carbon is attained . the resulting electrode is binder free and 100 % electrochemically active . energy densities up to 41 wh / kg in energy density 1 . 5 kw / kg in power density have been achieved .