Flow batteries have the potential to relieve and decentralize the power grids of the future due to their high efficiency, high number of cycles and the independent scalability of power and capacity. Flow batteries based on vanadium are currently the most widely used. However, this is toxic and expensive due to the limited reserves, which are restricted to a few countries (Russia, China and South Africa). Iron-based flow batteries are an alternative. Iron is available in large quantities worldwide and has a cost advantage over vanadium. The cooperation project combines the knowledge of six partners from Germany and Korea.

At the Seoul National University of Science and Technology (SNUST), inexpensive organometallic active materials based on iron and zinc or iron and cobalt, corresponding catalysts and aqueous alkaline electrolytes are being developed and tested for the anodic side. On the cathodic side, potassium hexacyanoferrate is used as the electrolyte. The Korea Institute of Science and Technology (KIST) is responsible for developing suitable membranes with chelated metal ions. Eisenhuth GmbH develops, produces and tests the bipolar plates. The flow field is being developed jointly with Clausthal University of Technology. Clausthal University of Technology is also testing the compatibility and stability of the individual components, investigating the electrochemical kinetics of the electrolyte and carrying out tests on individual cells. On this basis, stacks of 10 cells are to be developed, produced and tested by ETIS ltd. in Korea. The partner Korid Energy ltd. is responsible for expanding the stack to include the peripherals for the development of a complete battery system. Initially, small-scale prototypes of approx. 0.2 kW are to be produced and, after an intermediate step, larger systems with an output of 10 kW.

The aim of the project is to use new materials and economies of scale for larger systems to enable the market launch of economical flow batteries as a more environmentally friendly alternative to competing technologies.