First-principles thermal modeling of electric double layer capacitors under constant-current cycling

• Published in: Journal of power sources 2014, Vol.246, p.887-898
• Main Authors: D'ENTREMONT, Anna, PILON, Laurent
• Format: Article
• Language: English
• Subjects: Applied sciences; Capacitors. Resistors. Filters; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Heat transfer; Theoretical studies. Data and constants. Metering; Transport and storage of energy; Various equipment and components
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2013.08.024

This study aims to develop physical modeling and understanding of the coupled electrodiffusion, heat generation, and thermal transport occurring in electric double layer capacitors (EDLCs) during constant-current cycling. To do so, the governing energy equation was derived from first principles and coupled with the modified Poisson-Nernst-Planck model for transient electrodiffusion in a binary and symmetric electrolyte. In particular, irreversible Joule heating and reversible heat generation rates due to ion diffusion, steric effects, and changes in entropy of mixing in EDLCs were rigorously formulated. Detailed numerical simulations of the temperature rise in the electrolyte were performed for planar electrodes. The results qualitatively reproduced experimental data reported in the literature under various charging/discharging conditions.