A Blessing and a Curse: How a Supercapacitor's Large Capacitance Causes its Slow Charging
arXiv:1911.09924 · doi:10.1103/PhysRevLett.124.076001
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 timescales. 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 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.
arXiv commentC.L. and M.J. contributed equally to this work. 11 pages, 14 figures
References in corpus (13)
- Diffuse-Charge Dynamics in Electrochemical Systems
- Accelerating charging dynamics in sub-nanometer pores
- Molecular streaming and its voltage control in ångström scale channels
- Charge fluctuations in nano-scale capacitors
- Kinetics of Ion Transport in Ionic Liquids: Two Dynamical Diffusion States
- "Blue energy" from ion adsorption and electrode charging in sea- and river water
- Transient dynamics of electric double-layer capacitors: Exact expressions within the Debye-Falkenhagen approximation
- Coulometry and Calorimetry of Electric Double Layer Formation in Porous Electrodes
- Electrophoretic Properties of Highly Charged Colloids: A Hybrid MD/LB Simulation Study
- Curvature affects electrolyte relaxation: studies of spherical and cylindrical electrodes
- Lattice Boltzmann Electrokinetics simulation of nanocapacitors
- Transient response of an electrolyte to a thermal quench
- Impedance resonance in narrow confinement
Cited by in corpus (12)
- Classical dynamical density functional theory: from fundamentals to applications
- Charging Dynamics of Electrical Double Layers Inside a Cylindrical Pore: Predicting the Effects of Arbitrary Pore Size
- Transmission line circuit and equation for an electrolyte-filled pore of finite length
- Equivalent circuit and continuum modeling of the impedance of electrolyte-filled pores
- Electrification of water interface
- Frequency-dependent impedance of nanocapacitors from electrode charge fluctuations as a probe of electrolyte dynamics
- Convection can enhance the capacitive charging of porous electrodes
- Charging dynamics of electric double layer nanocapacitors in mean-field
- Computing the Local Ion Concentration Variations for Electric-Double-Layer-Modulation Microscopy
- Poisson-Nernst-Planck charging dynamics of an electric double layer capacitor: symmetric and asymmetric binary electrolytes
- Asymptotic analysis on charging dynamics for stack-electrode model of supercapacitors
- Three-Electrode Cell Calorimeter for Electrical Double Layer Capacitors