Electrochemical Characteristics of Titanium Carbide Derived Carbon|1-Ethyl-3-Methylimidazolium Tetrafluoroborate Electrical Double Layer Capacitors

Abstract

Symmetric two electrode supercapacitors were assembled in pure argon atmosphere (99,9999%) using titanium carbide derived carbon (C(TiC)) electrodes, TF4425 separator (from Nippon Kodoshi) and room temperature ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4) as an electrolyte. Cyclic voltammetry, electrochemical impedance and constant current charging/discharging data were used to describe the capacitive behavior of system studied in the temperature region from 25 to 80 °C. The limits of ideal polarizability, low-frequency limiting capacitance, time constant, time stability, and other characteristics have been calculated and discussed. Comparatively high gravimetric energy (40 Wh kg-1) and power (130 kW kg-1) per active C(TiC) weight have been calculated, weakly depending on temperature, if T {less than or equal to} 59 ºC. Results obtained have been compared with results for supercapacitors based on 1 M (C2H5)3CH3NBF4 in acetonitrile.