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arXiv · 2006.01989

Suppressed self-discharge of an aqueous supercapacitor using Earth-abundant materials

Samuel Devese·Thomas Nann
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Abstract

Supercapacitors (aka electrostatic double-layer capacitors -- EDLCs) offer excellent power storage capacity and kinetics, but suffer under rapid self-discharge. We introduced a zeolite framework into the active capacitor electrode, with the goal to tailor the free desorption energy and thus the self-discharge rate of supercapacitors. Low-cost carbonaceous materials and benchtop production methods were used to create supercapacitor electrodes with a measured specific capacitance of 17.25 F g$^{-1}$, a coulombic efficiency of 100%, and charge retention of over 25% over 24 hours determined by galvanostatic charge/discharge curve measurements. This charge retention was an enhancement of $\sim$350% compared with electrodes without zeolite coating.

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Samuel Devese, Thomas Nann. 2020-06-03. Suppressed self-discharge of an aqueous supercapacitor using Earth-abundant materials. https://arxiv.org/abs/2006.01989

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