<p>Graphene-based supercapacitors enable rapid charge–discharge owing to high electronic conductivity (~ 10^6 S m⁻¹), large theoretical surface area (~ 2630 m²&#xa0;g⁻¹), and chemical/mechanical robustness. Practical deployment is limited by sheet restacking, ion-transport constraints in dense films, and scale-up challenges. Here we compare three scalable graphene syntheses—chemical vapor deposition (CVD), electrochemical exfoliation, and microwave-assisted reduction—under consistent processing and testing conditions, and rank them by structural quality/defect density and industrial feasibility. Hybrid electrodes combining graphene with MnO₂, RuO₂, polyaniline (PANI), and polypyrrole (PPy) deliver enhanced performance: specific capacitance 312–500 F g⁻¹ at 0.5–1 A g⁻¹, energy density up to 120 Wh kg⁻¹, power density up to ~ 70&#xa0;kW&#xa0;kg⁻¹, and cycle retention ~ 92–95% after 10 000 cycles (6&#xa0;M KOH, room temperature; mean ± SD; n = 3–5). Charge-transfer resistance (R_ct) extracted from EIS remains low (≈1.2–1.4 Ω) and agrees with IR-drop estimates. Finally, we outline a compact AI-guided optimization concept that maps synthesis descriptors (route, time/temperature, ID/IG, BET area, mass loading) to performance targets (specific capacitance, energy, retention) using cross-validated regression to reduce experimental iteration. The results clarify quality–scalability trade-offs, quantify the role of hybridization, and identify microwave-assisted synthesis as a cost-effective, industry-oriented route within the tested window.</p>