A magnetically auto healable and robust supercapacitor from a nanocomposite of PANI68.1 %: Ni2O331.9 % (PNi) synthesized in an in situ single step method, is achieved. PNi provided an exceptional character of healing the structural damage of PANI by the magneticity of Ni2O3 nanoparticles and showed a feature of increase in energy storage with increase in No. of charge/discharge cycles. The PNi exhibited a cyclic stability up to 16,800 cycles without significant reduction in initial Cs. The energy storage parameters achieved after 10,000 cycles are specific capacitance (Cs) of 347.6 F g−1, specific energy (E) of 69.52 W h kg−1, which is in the regime of E of Ni-metal hydride batteries of 0.9–1.3 V potential range, and specific power (P) of 8.571 kW kg−1 at 3 A g−1. Therefore, the PNi would be of a potential electrode material for the fabrication of long withstanding, robust and self - magnetically healable supercapacitor that delivers high energy.