Ionic thermoelectric supercapacitors
2016 (English)In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 9, no 4, 1450-1457 p.Article in journal (Refereed) PublishedText
Temperature gradients are generated by the sun and a vast array of technologies and can induce molecular concentration gradients in solutions via thermodiffusion (Soret effect). For ions, this leads to a thermovoltage that is determined by the thermal gradient Delta T across the electrolyte, together with the ionic Seebeck coefficient alpha(i). So far, redox-free electrolytes have been poorly explored in thermoelectric applications due to a lack of strategies to harvest the energy from the Soret effect. Here, we report the conversion of heat into stored charge via a remarkably strong ionic Soret effect in a polymeric electrolyte (Seebeck coefficients as high as alpha(i) = 10 mV K-1). The ionic thermoelectric supercapacitor (ITESC) is charged under a temperature gradient. After the temperature gradient is removed, the stored electrical energy can be delivered to an external circuit. This new means to harvest energy is particularly suitable for intermittent heat sources like the sun. We show that the stored electrical energy of the ITESC is proportional to (Delta T alpha(i))(2). The resulting ITESC can convert and store several thousand times more energy compared with a traditional thermoelectric generator connected in series with a supercapacitor.
Place, publisher, year, edition, pages
ROYAL SOC CHEMISTRY , 2016. Vol. 9, no 4, 1450-1457 p.
Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:liu:diva-128769DOI: 10.1039/c6ee00121aISI: 000374351200029OAI: oai:DiVA.org:liu-128769DiVA: diva2:931779
Funding Agencies|European Research Council (ERC) ; Swedish foundation for strategic research (SSF); Knut and Alice Wallenberg foundation (KAW); Swedish Energy Agency; Wenner-Gren Foundations; Advanced Functional Materials Centre at Linkoping University2016-05-302016-05-302016-05-30