To eliminate electrolyte leakage, the development of safe and flexible supercapacitors necessitates solid-state electrolytes which integrate both high mechanical and electrochemical capabilities. Quasi-solid-state electrolytes, which constitute a polymer matrix along with an aqueous electrolytic phase, are a viable answer to this problem. Recently, gel electrolytes have gained a lot of attention in flexible and wearable electronic devices due to their remarkable advancements. However, the limitation in the multi-functional abilities and high-performance in such gels hinders the practical usage of such devices. On the electrochemical perspective, the performance of the gel electrolyte depends on the type of ionic carrier (acidic, alkaline, or salt-based), size of the ion, solvent concentration, type of polymer, as well as the interaction between the polymer and other components. Moreover, the performance of the electrolyte differs with the electrode-electrolyte interface and thus is highly dependent on the electrode material. For this reason, it is vital to carry a parametric study to evaluate the effect of the above stated. The aim of this study is to investigate the effect of changing the ionic carrier (namely H₃PO4, KOH and K₂SO₄) as well as the solvent concentration on architecturally engineered PVA-based electrolytes’ performance in free-standing CNT supercapacitor. In addition, the dependence of the electrolyte’s mechanical structure for long term stability is further evaluated by using the optimized concentration of each (H₃PO4, KOH and K₂SO₄) by freezing and de-freezing the gel to form membrane-like films as a result of the creation of increased physical cross-linking with this cycle. The supercapacitors are studied for their capacitance, charge/discharge capabilities as well their long-term stability.