Flow Battery Applications and Innovations - How is it possible to build an economic optimized redox-flow-batteries?

K. Pinkwart, J. Noack, L. Wietschel, N. Roznyatovskaya, P. Fischer, J. Tübke
Fraunhofer Institute for Chemical Technology,
Germany

Keywords: flow batteries, applications

Summary:

Redox-flow batteries are developed with a view to use the possibility of a long-term storage of the energy obtained from regenerative sources, for example wind and solar energy. Redox-flow batteries store electrical energy in fluids by chemical reactions which take place at a electrochemical converter system. The electrochemical energy converter in such a battery system is called stack and consists of several electrochemical cells stacked in a serial connection, often also called bipolar assembly. This configuration allow energy and power to be independently scaled and matched to the particular demand. Inorganic acids or bases in which metallic salts or other compounds are dissolved as redox active components act as the energy storage media. Beside this typical storage media there are also exist systems consisting of gases such as hydrogen and oxygen as well as organic substances. This great diversity of storage media leads to a variety of very different possible chemical reactions. Various cell structures with different electrode materials have been optimized to accelerate reactions and so increase power densities. Researchers and industry are interested in optimized systems in the view of costs and efficiency. It is important to discuss which components contribute in what ways to the total cost of a redox-flow battery system. It is important to know and understand the general effects of different battery parameters on system costs. This presentation focuses on relations of material choice and costs of Redox Flow Battery Systems. The main objective is the link between the cost and performance parameters of single components and the overall costs of a battery system. From this knowledge it is possible to draw conclusions for the minimization of system costs in a targeted manner.