OATAO - Open Archive Toulouse Archive Ouverte Open Access Week

On the Dynamics of Charging in Nanoporous Carbon-Based Supercapacitors

Péan, Clarisse and Merlet, Céline and Rotenberg, Benjamin and Madden, Paul Anthony and Taberna, Pierre-Louis and Daffos, Barbara and Salanne, Mathieu and Simon, Patrice On the Dynamics of Charging in Nanoporous Carbon-Based Supercapacitors. (2014) ACS Nano, 8 (2). 1576-1583. ISSN 1936-0851

[img]
Preview
(Document in English)

PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
500kB

Official URL: http://dx.doi.org/10.1021/nn4058243

Abstract

Supercapacitors are electricity storage systems with high power performances. Their short charge/discharge times are due to fast adsorption/desorption rates for the ions of the electrolyte on the electrode surface. Nanoporous carbon electrodes, which give larger capacitances than simpler geometries, might be expected to show poorer power performances because of the longer times taken by the ions to access the electrode interior. Experiments do not show such trends, however, and this remains to be explained at the molecular scale. Here we show that carbide-derived carbons exhibit heterogeneous and fast charging dynamics. We perform molecular dynamics simulations, with realistically modeled nanoporous electrodes and an ionic liquid electrolyte, in which the system, originally at equilibrium in the uncharged state, is suddenly perturbed by the application of an electric potential difference between the electrodes. The electrodes respond by charging progressively from the interface to the bulk as ions are exchanged between the nanopores and the electrolyte region. The simulation results are then injected into an equivalent circuit model, which allows us to calculate charging times for macroscopic-scale devices.

Item Type:Article
Additional Information:Thanks to ACS editor. The original publication is available at http://pubs.acs.org/doi/abs/10.1021/nn4058243
HAL Id:hal-01116494
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Université de Toulouse > Institut National Polytechnique de Toulouse - INPT (FRANCE)
Other partners > Université Pierre et Marie Curie, Paris 6 - UPMC (FRANCE)
Université de Toulouse > Université Toulouse III - Paul Sabatier - UPS (FRANCE)
Other partners > Ecole supérieure de physique et de chimie industrielles ParisTech - ESPCI (FRANCE)
Other partners > University of Oxford (UNITED KINGDOM)
Laboratory name:
Statistics:download
Deposited By: cirimat webmestre
Deposited On:11 Apr 2014 08:21

Repository Staff Only: item control page