Electrochemical Double Layer Capacitors Based on Propylene Carbonate Solution Operating from −45°C to 100°C

Abstract

The electrochemical characteristics of the electrical double layer capacitors consisting of the microporous titanium carbide derived carbon (TiC-CDC) electrode in 1 M (C2H5)3CH3NBF4 solutions in 4-methyl-1,3-dioxolan-2-one, (so-called propylene carbonate (PC)) have been studied using cyclic voltammetry and electrochemical impedance spectroscopy methods from −45°C to 100°C. The specific capacitance, phase angle and series resistance values dependent on the solvent system used and temperature applied (from −45°C to 100°C) have been established. The region of ideal polarizability ΔE ≥ 3.0 V has been demonstrated for TiC-CDC electrodes at all temperatures investigated. Specific conductivity and viscosity values have been obtained and correlated with electrochemistry data. The limiting capacitance, characteristic time constant and complex power values depend noticeably on the temperature applied, i.e. on the viscosity and specific conductivity determining the series resistance and capacitance of the electrode | electrolyte solution interface.