Model of Supercapacitor Electrodes Based on Nanostructured Materials

The substantiation of an extended model of the equivalent electric circuit of supercapacitor electrodes based on nanostructured materials taking into account the change in the characteristics of charge transport in the electrolyte–electrode material system at various frequencies depending on the thickness of the electrode material is presented. The model is aimed at predicting the impedance characteristics of supercapacitors depending on the conductivity of the electrolyte, the characteristics of the pores, and the thickness of the nanostructured material of the electrode. Good agreement is obtained between the results of calculation and experimental data. Within the framework of the model, the decrease in the specific electrical capacitance of supercapacitors with an increase in the thickness of the electrode material is explained by the significant influence of the relatively small values of the electrolyte resistance in the space between the powder particles and the contact resistance between the electrode material particles.