Long Period Operation of Ionic Liquid Based Electrical Double Layer Capacitor at 45 ℃ and 3 V

Abstract

The long period operation at 45 ℃ and 3 V of the mesoporous carbon-ionic liquid-carbon covered aluminum foam based electrical double layer capacitor was studied. The composite electrode sheet was formed by embedding mesoporous carbon with carbon-coated aluminum foam, and the 3 cm×5 cm pouch was composed of EMIBF4 as electrolyte. The operation law of charge and discharge was studied at 45 ℃ and 3 V for 1 500 h. It is found that the internal resistance change rate is about 10%, and the capacitance retention rate is as high as 98%, both of which are far better than those of organic liquid-based electrical double layer capacitor at 2.7 V and 65 ℃. The gas generation of pouches at 2.7 V/65 ℃ and 3 V/45 ℃ was compared. It is proved that the soft package of mesoporous carbon-ionic liquid-carbon-coated aluminum foam based electrical double layer capacitor can work stably at 3 V, 45 ℃ for 1 500 h. It provides a solid foundation for further promoting the application of ionic liquid-based electrical double layer capacitor.

Keywords

• energy storage
• electrical double layer capacitor
• ionic liquid
• carbon-coated aluminum foam
• mesoporous carbon
• high temperature aging