Abstract
The development of novel electrolytes and electrodes for supercapacitors is hindered by a gap of several orders of magnitude between experimentally measured and theoretically predicted charging time scales. Here, we propose an electrode model, containing many parallel stacked electrodes, that explains the slow charging dynamics of supercapacitors. At low applied potentials, the charging behavior of this model is described well by an equivalent circuit model. Conversely, at high potentials, charging dynamics slow down and evolve on two relaxation time scales: a generalized
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C
time and a diffusion time, which, interestingly, become similar for porous electrodes. The charging behavior of the stack-electrode model presented here helps to understand the charging dynamics of porous electrodes and qualitatively agrees with experimental time scales measured with porous electrodes.
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C
time and a diffusion time, which, interestingly, become similar for porous electrodes. The charging behavior of the stack-electrode model presented here helps to understand the charging dynamics of porous electrodes and qualitatively agrees with experimental time scales measured with porous electrodes.
Original language | English |
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Article number | 076001 |
Pages (from-to) | 1-6 |
Number of pages | 6 |
Journal | Physical Review Letters |
Volume | 124 |
Issue number | 7 |
DOIs | |
Publication status | Published - 20 Feb 2020 |
Keywords
- Capacitance
- Electrochemistry
- Electrokinetic flows
- Thermodynamics
- Porous media
- Nonequilibrium systems
- Capacitors