Sustainable Materials for Electrochemcial Capacitors

6Ionic Liquids for Supercapacitors

Guocai Tian

State Key Laboratory of Complex Non-Ferrous Metal Resource Clean Utilization, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming, China

Abstract

Supercapacitor is a new generation of energy storage device between rechargeable battery and common capacitor. They have been widely concerned and applied because of their fast charging and discharging speed, high-energy storage density, small volume, long cycle life and little environmental pollution. However, the low-energy density of supercapacitors limits their further applications. Improving energy density has become a challenge for its further development and application. Electrolyte is one of the most important factors in super capacitors. The research and development of new electrolytes with high efficiency, stability, green and low price to improve the energy density of supercapacitors is the main research hotspot in this field. In the past decades, many new high-performance electrolytes have been developed and used to improve the performance of supercapacitors. In this chapter, we mainly focus on the research progress and future research direction of ionic liquids as new green electrolytes for supercapacitors. We briefly introduced the related knowledge and properties of supercapacitors and ionic liquids. The research progress of pure ionic liquids, functional ionic liquids, mixed systems of ionic liquids and ionic liquids, ...