Copper ferrite (CuFe2O4), a cost-effective and promising supercapacitive electrode material, was doped with highly electroactive nickel using a simple microwave combustion process. The presence of nickel was found to enhance the electrode kinetics and favor the fast diffusion process when the material was used to construct a supercapacitor. The nickel-blended copper ferrite (Cu0.7Ni0.3Fe2O4) exhibited a specific capacitance of 1050 Fg−1 at a current density of 1 Ag−1 in 2 M KOH electrolyte solution. Furthermore, a reasonable rate of performance and better cyclic stability were observed with the material. Also, an asymmetric type of supercapacitor device was fabricated using CuNiFe2O4 electrodes, and the electrochemical performance was analyzed. The fabricated device showed an energy density of 21.5 Wh kg−1 and a power density of 417 W kg−1. These electrochemical investigations suggest the potential application of Cu0.7Ni0.3Fe2O4 as a supercapacitor electrode material for achieving superior performance.