New Membrane as Key Component For Energy Storage Technology

Aachen, Germany/Seoul - Storing fluctuating and delivering stable electric power supply are central issues when using energy from solar plants or wind power stations.

Here, efficient and flexible energy storage systems need to accommodate for fluctuations in energy gain. Scientists now significantly improved a key component for the development of new energy storage systems.

Water was the biggest problem Redox flow batteries use electrolytes to store energy. Being separated by a membrane, two energy-storing electrolytes circulate in the system. The storage capacity depends on the amount of electrolytes and can easily be increased or decreased depending on the application. To charge or discharge the battery, the vanadium ions are chemically oxidized or reduced while protons pass the separating membrane. The membrane plays a central role in this system: On the one hand, it has to separate the electrolytes to prevent energy loss by short-circuiting. On the other hand, protons need to pass the membrane when the battery is charged or discharged. The current benchmark is a Nafion membrane. But Nafion and similar polymers swell when exposed to water and loose their barrier function for vanadium ions.

Researchers tried a different approach Chemists try to prevent vanadium leakage by changing the molecular structure of such membranes. The researchers from the Leibniz Institute for Interactive Materials (DWI), RWTH Aachen University and Hanyang University in Seoul came up with a completely different approach:

Source: IWR Online, 02 Aug 2016