Schaltin Stijn, Li Yun, Brooks Neil R, Sniekers Jeroen, Vankelecom Ivo F J, Binnemans Koen, Fransaer Jan
KU Leuven, Department of Materials Engineering, Kasteelpark Arenberg 44, Box 2450, 3001 Leuven, Belgium.
Chem Commun (Camb). 2016 Jan 7;52(2):414-7. doi: 10.1039/c5cc06774j. Epub 2015 Nov 3.
The first redox flow battery (RFB), based on the all-copper liquid metal salt [Cu(MeCN)4][Tf2N], is presented. Liquid metal salts (LMS) are a new type of ionic liquid that functions both as solvent and electrolyte. Non-aqueous electrolytes have advantages over water-based solutions, such as a larger electrochemical window and large thermal stability. The proof-of-concept is given that LMSs can be used as the electrolyte in RFBs. The main advantage of [Cu(MeCN)4][Tf2N] is the high copper concentration, and thus high charge and energy densities of 300 kC l(-1) and 75 W h l(-1) respectively, since the copper(i) ions form an integral part of the electrolyte. A Coulombic efficiency up to 85% could be reached.
