A facile and rapid microwave synthesis method was used to make Co/Ni-carbon black (CB) nanocomposites. Several sophisticated techniques confirm the formation and the effects of carbon nanoparticles incorporated into Co/Ni-CB composites. Carbon engrafted Co/Ni composite demonstrates excellent morphology, more significant area, and higher conductive region, thus improving electrode/electrolyte accessibility to enhance electrochemical kinetics. The interaction and combination of CB with Co/Ni composite shows excellent capacitive behavior, assessed by galvanostatic discharge method, cyclic voltage voltammetry, and electrochemical impedance spectroscopy. CB plays a crucial role in stimulating the formation of robust structures, surface activity, and specific capacitance through enhancing electron transport and catalytic properties. This electrode material (NX3) has the highest specific capacitance of 748 Fg−1 at scan rates of 5 mVs−1 and was found to have excellent cycle stability (92.8%) over 5000 cycles. Solid-state supercapacitors fabricated from developed electrodes are highly effective for brightening LEDs. In this study, we demonstrated for the first time a single-step technique that is both quick and efficient for the synthesis of Co/Ni-carbon black heterostructure by using microwave irradiation. The present work suggests that low-cost electrodes can be used in a wide range of future energy storage systems as a potential hybrid material.