Single-electrode transient behavior was measured mainly during the discharging process for a model cell of electric double layer capacitor with nano-porous carbon electrodes and reference electrode. Apparent conductivity in the cell, which we call "effective conductivity," is determined with approximation of current in transient behavior to a one-dimensional electrophoretic model. A comparison of effective conductivity with conductivity of bulk solution suggests an interesting mechanism of transfer of electrolyte ions. The difference in transient behavior between various electrolyte ions was not conspicuous in spite of distinctive differences in conductivity of each bulk solution. The large pare diameter of the carbon electrode results in rapid transient behavior and such an electrode should be suitable for rapid charge and discharge. The effect of origin of carbon electrode is found to be significant to bring considerable differences in discharge rate. However, the difference in transient behavior that was caused by materials for carbon electrode becomes smaller for lower concentrations of electrolyte solution. Effective conductivities for all experiments do not directly reflect conductivities of bulk solution of each electrolyte. This implies that electrolyte ions are transported based not only on the electrophoretic effect, but also on a mechanism similar to surface diffusion.