Rev.Adv.Mater.Sci.(RAMS)
No 2, Vol. 14, 2007, pages 151-156

INTERCALATION PSEUDO-CAPACITANCE IN CARBON SYSTEMS OF ENERGY STORAGE

B.P. Bakhmatyuk, B.Ya. Venhryn, I.I. Grygorchak, M.M. Micov and S.I. Mudry

Abstract

he contribution of intercalative pseudo-capacitance of K+ and Cs+ ions to the total capacitance of activated carbons' aqueous solutions of KOH (7.6m) and CsBr (3.16m) electrolyte interface has been studied. It is shown on the basis of experimental and calculated porometric, thermodynamic parameters, and capacitive dependences that the measured values of specific capacity (160-260 F/g) exceeding the characteristic value of 150 F/g (for the capacitance of a double electric layer) are due to intercalative pseudo-capacitance. A computer simulation of impedance data for an equivalent electric circuit of a double electric layer and using the Stern model allowed us to determine the increase of pseudo-capacitance during K+ ions' cathode intercalation process in activated carbon from the initial potential to the maximum charge, i.e. from C=490 F/g to C=996 F/g.

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