title: An Aqueous Redox-Flow Battery with High Capacity and Power: The TEMPTMA/MV System.
abstract: Redox-flow batteries (RFB) can easily store large amounts of electric energy and thereby mitigate the fluctuating output of renewable power plants. They are widely discussed as energy-storage solutions for wind and solar farms to improve the stability of the electrical grid. Most common RFB concepts are based on strongly acidic metal-salt solutions or poorly performing organics. Herein we present a battery which employs the highly soluble N,N,N-2,2,6,6-heptamethylpiperidinyl oxy-4-ammonium chloride (TEMPTMA) and the viologen derivative N,N'-dimethyl-4,4-bipyridinium dichloride (MV) in a simple and safe aqueous solution as redox-active materials. The resulting battery using these electrolyte solutions has capacities of 54 Ah L-1, giving a total energy density of 38 Wh L-1at a cell voltage of 1.4 V. With peak current densities of up to 200 mA cm-2the TEMPTMA/MV system is a suitable candidate for compact high-capacity and high-power applications.
authors.affiliation: Lehrstuhl für Organische und Makromolekulare Chemie (IOMC), Friedrich-Schiller-Universität Jena, Humboldtstrasse 10, 07743, Jena, Germany.|Center for Energy and Environmental Chemistry Jena (CEEC Jena), Friedrich-Schiller-Universität, Philosophenweg 7a, 07743, Jena, Germany.
authors.forename: Tobias
authors.initials: T
authors.lastname: Janoschka
authors.affiliation: JenaBatteries GmbH, Botzstrasse 5, 07743, Jena, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Martin
authors.affiliation: Lehrstuhl für Organische und Makromolekulare Chemie (IOMC), Friedrich-Schiller-Universität Jena, Humboldtstrasse 10, 07743, Jena, Germany.|Center for Energy and Environmental Chemistry Jena (CEEC Jena), Friedrich-Schiller-Universität, Philosophenweg 7a, 07743, Jena, Germany.
authors.forename: Martin D
authors.initials: MD
authors.lastname: Hager
authors.affiliation: Lehrstuhl für Organische und Makromolekulare Chemie (IOMC), Friedrich-Schiller-Universität Jena, Humboldtstrasse 10, 07743, Jena, Germany. ulrich.schubert@uni-jena.de.|Center for Energy and Environmental Chemistry Jena (CEEC Jena), Friedrich-Schiller-Universität, Philosophenweg 7a, 07743, Jena, Germany. ulrich.schubert@uni-jena.de.
authors.forename: Ulrich S
authors.initials: US
authors.lastname: Schubert
keywords: electrochemistry; energy storage; radicals; redox chemistry; redox-flow battery