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We report the effect of mechanical alloying on the chemically synthesized NiCo 2 O 4 nanowire for better electrochemical performance. The nickel cobaltite nanowires (NC) were successfully synthesized via the hydrothermal method without any surfactant. Then they were milled for 1 h (NC1) and 2 h (NC2) to boost the electrochemical performance. The structural and microstructural parameters, shape, size, and morphology of these samples are revealed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) techniques. The Brunauer−Emmett−Teller (BET) characterization and Barrett−Joyner−Halenda (BJH) model reveal that the NC1 sample offers the highest specific surface area among all three samples with its one-dimensional mesoporous structure (pore diameter, ∼7 nm). The NC1 sample displays an excellent specific capacitance and rate capability (1234 F g −1 at a scan rate of 2 mV s −1 ). However, upon further milling (2 h) the electrochemical performance of the sample decays rapidly due to an increase in particle size and reduction in specific surface area. A remarkable specific capacity of 1196 F g −1 is achieved in the 1 h milled sample at the lowest current density of 12 A g −1 , and at 40 A g −1 and 129.2 F g −1 specific capacitance can be retained. We further demonstrate an asymmetric device based on the NC1 sample as a positive electrode, which produces an excellent energy density of 59.221 Wh kg −1 at a power density of 1065.4 W kg −1 . The assembled device can attain an outstanding power density of 10.992 kW kg −1 at an enormous high current density of 13.33 A g −1 and demonstrates an excellent cyclic performance of 91.7% retention after 5000 cycles.