Dynamical theory for the battery's electromotive force
Abstract
We propose a dynamical theory of how the chemical energy stored in a battery generates the electromotive force (emf). In this picture, the battery's half-cell acts as an engine, cyclically extracting work from its underlying chemical disequilibrium. We show that the double layer at the electrode-electrolyte interface can exhibit a rapid self-oscillation that pumps an electric current, thus accounting for the persistent conversion of chemical energy into electrical work equal to the emf times the separated charge. We suggest a connection between this mechanism and the slow self-oscillations observed in various electrochemical cells, including batteries, as well as the enhancement of the current observed when ultrasound is applied to the half-cell. Finally, we propose more direct experimental tests of the predictions of this dynamical theory.
- Publication:
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Physical Chemistry Chemical Physics (Incorporating Faraday Transactions)
- Pub Date:
- April 2021
- DOI:
- 10.1039/D1CP00196E
- arXiv:
- arXiv:2010.16400
- Bibcode:
- 2021PCCP...23.9428A
- Keywords:
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- Physics - Chemical Physics;
- Condensed Matter - Mesoscale and Nanoscale Physics;
- Condensed Matter - Materials Science
- E-Print:
- 11 pages, 5 figures + appendix (2 pages, no figures). v3: some points further clarified in text, references improved, minor typos fixed. To be published in PCCP