Author:

Keywords:

redox flow batteries, anion exchange membrane, nonaqueous redox flow batteries, copper, ionic liquids, Science & Technology, Physical Sciences, Technology, Chemistry, Physical, Electrochemistry, Energy & Fuels, Materials Science, Multidisciplinary, Chemistry, Materials Science, Anion exchange membrane, PPO, Cross-linking, Non-aqueous RFBs, Ionic liquids, Copper, SUPPORTING ELECTROLYTES, POROUS MEMBRANES, PENDANT GROUPS, TRANSPORT, POLYMERS, SOLVENTS, PYRIDINE, 03 Chemical Sciences, 09 Engineering, Energy, 34 Chemical sciences, 40 Engineering

Abstract:

A stable and eco-friendly anion-exchange membrane (AEM) was prepared and applied in a non-aqueous all-copper redox flow battery (RFB). The AEM was prepared via a simple procedure, leading to a cross-linked structure containing quaternary ammonium groups without involvement of harmful trimethylamine. A network was thus constructed which ensured both ion transport and solvent resistance. The ion exchange capacity (IEC) of the membrane was tuned from 0.49 to 1.03 meq g−1 by varying the content of the 4, 4′-bipyridine crosslinking agent. The membrane showed a good anion conductivity and retention of copper ions. As a proof of principle, a RFB single cell with this crosslinked membrane yielded a coulombic efficiency of 89%, a voltage efficiency of 61% and an energy efficiency of 54% at 7.5 mA cm−2.