Correlation between the pore and solvated ion size on capacitance uptake of PVDC-based carbons

Abstract

A nonaqueous electrolyte solution is employed to form double layers on a poly(vinylidene chloride) (PVDC)-based carbon material, thereby extending the application of PVDC-based carbon to nonaqueous systems. Thermal behavior of the Npv-series, which was obtained by simple heat treatment under an inert atmosphere, and the Apv-series, which is obtained by potassium hydroxide (KOH) addition, is confirmed by thermal gravimetric analysis (TGA). The KOH activation affect on the structure of PVDC-based carbon is shown and demonstrates a high capacitance in nonaqueous electrolyte systems. Variation of the pore size distribution on the double layer capacitance is explained on the basis of computer simulation. Carbons with different porous structures are prepared by KOH impregnation as a function of heat-treatment temperature (HTT). The effects of the porous structure on the electrochemical behavior and the capacitance of the resulting electric double layer capacitors (EDLCs) are investigated.