High electrical conductivity is a crucial factor for improving the electrochemical performance of energy storage materials. In the work, amorphous Ni-C nanoparticles with high electric conductivity are fabricated by mechanical alloying and are used as a novel cathode for supercapacitors. It is shown that the amorphous Ni-C retains a high specific capacitance and remarkable cycling stability after the electrode is activated by chronopotentiometry at 0.5 A g(-1), and even more gratifyingly, the rate capability of the material is superior to that of other Ni based materials due to its high electrical conductivity, which is convenient for fast electron transfer in active material and fast reversible Faradic reaction characteristics. Finally, an asymmetric supercapacitor based on Ni-C as the positive electrode and activated carbon as the negative electrode could be cycled reversibly at a high working potential of 0-1.6 V and delivered a high energy density of 39.8 Wh kg(-1). These results confirm the significance and tremendous potential of amorphous Ni-C materials for the development of high-performance energy supply systems. (C) 2017 Elsevier B.V. All rights reserved.