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Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature
Published on: December 20, 2016
Energy storage inspired by nature - ionic liquid iron-sulfur clusters as electrolytes for redox flow batteries
Christian Modrzynski1, Peter Burger
1Institut für Anorganische und Angewandte Chemie, Department Chemie, Universität Hamburg, Martin-Luther-King-Platz 6, 20146 Hamburg, Germany. burger@chemie.uni-hamburg.de.
Abstract:
The redox flow battery (RFB) is a promising technology for the storage of electric energy. Many commercial RFBs are often based on acidic vanadium electrolyte solutions that have limitations regarding stability and energy density. Here, a new approach is presented that is inspired by nature's electron storage, i.e. iron-sulfur clusters [Fe4S4(SR)4]2-. In combination with imidazolium cations, new ionic liquid electrolyte materials were obtained and characterized with regard to their physico- and electrochemical properties. For flow battery tests, the bromide/bromine redox-couple was used in the second half cell in an ionic liquid solution. In these measurements, liquid iron-sulfur clusters show high coulombic (>95%) and energy (69%) efficiencies combined with a high theoretical energy density (88 W h L-1).
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