An in-depth investigation into the influence of temperature on the electrochemical behavior of electric double-layer capacitors containing ethyl isopropyl sulfone-based electrolytes

The surrounding temperature significantly impacts the electrochemical behavior of electric double-layer capacitors during operation. While low temperatures restrict the transport properties of the charge carriers and lower the overall cell performance, higher temperatures improve the transport properties and performance but lead to the decomposition of the materials. To address this issue, the supercapacitor’s nominal voltage must be
lowered to ensure a long cycle life. With the aim of understanding the temperature-dependent behavior of supercapacitors based on ethyl isopropyl sulfone and acetonitrile, various electrochemical investigations at different temperatures up to 80 ◦C are presented. Interestingly, these investigations reveal a contradictory performance evolution over the temperature caused by the different solvents. Supported by the different stabilities of these two electrolytes, different optimal temperature ranges of application for electric double-layer capacitors based on these solvents can be concluded from these findings.