Coal based nanofibers were prepared by electrospinning a mixture of polyacrylonitrile and acid treated coal. Coal based activated carbon fibers were further obtained by carbonization and steam activation. The effects of acid treatment on raw coal were studied to explain the enhanced solubility in various solvents. The solubility of coal was as high as 6.6 wt% in N,N-dimethylformamide. The electrochemical performance of supercapacitor electrodes using coal based activated carbon fiber mats was then studied. This binder-free electrode showed a specific capacitance of 230 F g−1 at a current density of 1 A g−1 and an excellent capacity retention of 97% after 1000 cycles.