Wide-temperature range operation supercapacitors from nanostructured activated carbon fabric

摘要

Electrochemical power sources that offer high energy and power densities and, can also withstand a harsh temperature range have become extremely desirable in applications ranging from civilian portable electronic devices to military weapons. In this report, we demonstrated a wide temperature withstanding supercapacitor which can be operated from 100℃ to -40℃ within a voltage window from -2V to 2V. The performance of the supercapacitor coin cells, assembled with nanostructured activated carbon fabric (ACF) as the electrode material and 1 M tetraethylammonium tetrafluoroborate (TEABF_4) in polypropylene carbonate (PC) solution as the electrolyte, was systematically studied within the set temperature window. The ACF supercapacitor yielded ideal rectangular shapes in cyclic voltammograms within 0-100℃ with an average mass capacitance of 90Fg~(-1) and,60Fg~(-1) at-25℃. The capacitance was still over 20 Fg~(-1) at the extremely low temperature of -40℃. Another exciting feature of the ACF supercapacitors was that they resumed their room temperature capacitance when cooled from 100℃ and defrosted from -40 ℃, demonstrating an excellent repeatability and stability. The charge-discharge behavior of the ACF supercapacitors showed long-cycle stability at extreme temperatures. These high electrochemical performances make this type of supercapacitors very promising in many practical applications.