Thermal influence on the electrochemical behavior of a supercapacitor containing an ionic liquid electrolyte
Journal article, 2018

Emerging demands on heat-durable electronics have accelerated the need for high temperature supercapacitors as well as for understanding the influence of elevated temperatures on the capacitive behavior. In this work, we present a comprehensive study of the thermal influence on a supercapacitor containing 1-ethyl-3-methylimidazolium acetate (EMIM Ac) electrolyte and activated carbon (AC) electrodes. The performance variation as a function of temperature in a range from 21 °C to 150 °C reveals that a high specific capacitance of 142 F g−1 can be achieved at 150 °C at a current density of 2 A g−1 with a rate capability of 87% at 15 A g−1 (relative to 2 A g−1). At 150 °C, equivalent series resistance (ESR) is only 0.37 Ω cm2, which is a result of improved ionic conductivity of the electrolyte at elevated temperature. The ESR value of 2.5 Ω cm2 at room temperature reflects a good compatibility between EMIM Ac and AC. In addition, a capacitance retention of more than 95% (in the end of 1000 cycles) is maintained up to120 °C followed by 85% at 150 °C. These results confirm EMIM Ac as a suitable candidate for carbon-based high temperature supercapacitors, and the observations regarding the thermal influence on performance metrics e.g. usable operation voltage could be applicable to other energy storage devices.

Relaxation time constant

Ionic liquid electrolyte

Supercapacitor

Cyclic stability

High temperature

Author

Mohammad Mazharul Haque

Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory

Qi Li

Chalmers, Microtechnology and Nanoscience (MC2)

Anderson David Smith

Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory

Volodymyr Kuzmenko

Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory

Elof Köhler

Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory

Per Lundgren

Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory

Peter Enoksson

Chalmers, Microtechnology and Nanoscience (MC2), Electronics Material and Systems Laboratory

Electrochimica Acta

0013-4686 (ISSN)

Vol. 263 249-260

Driving Forces

Sustainable development

Areas of Advance

Transport

Production

Energy

Materials Science

Subject Categories

Chemical Sciences

DOI

10.1016/j.electacta.2018.01.029