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We introduced the concept of a novel hybrid faradaic structure as a mechanism to improve the performance of biomass-derived carbon-based supercapacitors (SCs). Organic-inorganic hybrid composition, nanostructures, porosity, surface area and active redox reactions were carefully designed. We reported the facile, cost-effective and environmentally friendly fabrication of pure lignin carbon nanofibers (LCNFs) incorporated with flower-like, multi-metal and intrinsically capacitive (Ni-Co@MnO 2) nanoparticles in a flexible and binder-free electrode for SCs by the electrospinning technique using various electrolytes (1 M Na 2 SO 4 , 0.5 M KI and 1 M Na 2 SO 4 +0.5 M KI). Mechanically robust LCNFs were used as a free-standing electrode and characterized for electrochemical performance using a two-electrode system in a Swagelok cell. Specific capacitance of the LCNFs in 1 M Na 2 SO 4 electrolyte (current density 0.1 A/g) of 129 F/g increased to 200 F/g when adding 1 % manganese oxide nanoparticles that introduced intrinsic capacitance into the nanofibers. This value further increased to 303 F/g by adding 1 % Ni-Co to the manganese oxide. The nanoflower morphology significantly increased the surface area via micro and mesopore modification on carbonization and via macropore expansion on activation. After applying a mixed electrolyte (1 M Na 2 SO 4 + 0.5 M KI), the capacitance reached 400 F/g and remained stable up to 1000 GDC cycles. Using the same composite nanofibers, 1,021 F/g was achieved using 0.5 M KI as an electrolyte. However, the latter system appeared unstable beyond 200 GDC cycles, suggesting that it can be applied as a disposable fast-charge supercapacitor. In the presence of a chemically-stable, highly-porous and partially-conductive carbon matrix, we concluded that interplay between the multi-metal oxides and electrolytes increased oxidation numbers, thereby boosting the faradaic reaction and enhancing electronic conductivity. [Display omitted] • EDLC carbon-based supercapacitor was fabricated from flower-like Ni-Co@MnO 2 nanoparticles and biomass lignin. • The unique metal oxide nanostructure led to highly-porous carbon nanofibers with unblocked micro-, meso- and macropores. • Mixed electrolyte of Na 2 SO 4 and KI led to capacitance of 400 F/g up to 1000 GDC cycles. • With KI as electrolyte, capacitance of 1,021 F/g was achieved and stable up to 200 GDC cycles. [ABSTRACT FROM AUTHOR]