Figure 4.

a) Total resistance versus length of the electrode; calculation of the electrode conductivity by transfer length method. 3D schema of EDL for b) GSSC and c) GPUSC. 3D schema describing the formation of EDL and charging mechanism for GSSC, GPUSC, and GS/GPUSC, comprising: d) ions distribution before applying potential, e) ion absorption while charging the SC electrodes, and f) positive and negative ions diffusion from H₃PO₄ electrolytes to the electrodes of SC after charged. g) I–V curves of GSSC, GPUSC, and GS/GPUSC measured during charging.