In this work, a supercapacitor device with a graphene/hexagonal boron nitride (hBN) electrode and KCl electrolyte was simulated to investigate its electrochemical performance. Key parameters such as potential and current of the cell, ion concentration ( \(\hbox {K}^+\) and \(\hbox {Cl}^-\) ), electrode and electrolyte potential, and total current density at the interface were analyzed over time. The electrode current density as a function of electrode potential was also studied. The results demonstrated a maximum specific capacitance of 624.72 F/g at a current density of \(-\hbox {1.08 A/cm}^2\) and a potential of 0.116 V, confirming the system’s behavior within the supercapacitor range. Additionally, the maximum power dissipation density was 54.13 \(\hbox {W/cm}^3\) at a current density of −0.61 \(\times\) \(\hbox {10}^{-4}\) \(\hbox {A/cm}^2\) . These findings highlight the potential of KCl as an effective electrolyte in graphene/hBN-based supercapacitors, paving the way for enhanced energy storage technologies.
