A novel ring-shaped NiS-poly-2-aminothiophenol NiO (NiS-P2ATP/NiO) core-shell nanocomposite has been successfully synthesized and extensively analyzed, presenting itself as a promising material for a two-electrode configuration pseudo-supercapacitor, tested in both basic and acidic mediums. The SEM analysis reveals the construction of open-ring shapes, characterized by a wall thickness of approximately 120 nm and a height of around 100 nm. To confirm the elements and crystallinity behavior of this nanocomposite, XPS and XRD analyses are used, while FTIR is performed to confirm the functional groups. The electrical properties of this nanocomposite were thoroughly investigated through various techniques, including charge/discharge, cyclic voltammetry, and EIS. The efficiency of the fabricated supercapacitor was assessed through measured specific capacitance (CS), energy density (E), power density (P), Ragone plot, and the values of RS and RCT resistances. The specific capacitance value is significantly higher at 59.8 F/g compared to the basic medium's CS value of 30 F/g. In the acidic medium, the E values reached 5.0 W h kg-1, while in the basic electrolyte, it amounted to 2.5 W h kg-1. The produced P achieved impressive values, reaching 28800 and 28700 W/kg at 0.2 A/g in the acidic and basic mediums, correspondingly. The unique behavior of this novel composite suggests its potential for industrial applications of polymer materials, given its ease of preparation, mass production feasibility, and cost-effectiveness. The findings of this study open doors for the practical implementation of such innovative materials in energy storage technologies.