Supercapacitor Degradation and Life-time

conference paper

English

Degradation of supercapacitor (SC) is evaluated during aging tests. Continuous current cycling for 100% energy and 75% energy and discontinuous cycling for 75% energy, respectively, was performed on two different types of supercapacitors. SC parameters are determined before the aging test, and during 6x105 cycles of all three current cycling tests. Capacitance fading within the current cycling tests is correlated to the results of capacitance change within the calendar life tests at different temperatures and operating voltage. Two studied SCs technologies show different sensitivity to temperature and electric field during the calendar tests as well as slightly different evolution of capacitance during cycling. We show that the capacitance fading is driven by two mechanisms. The first one can be covered by the exponential function of square root of time of ageing, while the second one is described by the Gaussian function. The first ageing mechanism, related probably to the electrolyte parameters degradation, is observed for all the tested samples, while the second mechanism emerge only in case of hard testing conditions – elevated temperature and/or increased operating voltage. We suppose that the second ageing mechanism is related to the electrode active area degradation caused probably by the decrease of potential barrier on the electrode/electrolyte interface. Further is shown that, for the same cycling current, the longer charge/discharge time accelerates the SC’s degradation.

Supercapacitor; degradation; life-time;

SEDLÁKOVÁ, V.; ŠIKULA, J.; MAJZNER, J.; SEDLÁK, P.

9. 9. 2019

European Passive Components Institute s.r.o.

Brno

978-80-907447-0-7

Proceedings of 2nd Passive Components Networking Symposium

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