Redox-flow batteries

Redox-flow batteries are highly efficient and have a longer service life than conventional batteries. As the energy is stored in external tanks, the battery capacity can be scaled independently of the rated battery power. We offer expertise in the following areas:

Material development and characterization

Materials for redox-flow batteries are investigated and further developed. Our work includes the characterization of battery materials, investigations into long-term stability and the development of corrosion-stable bipolar plates.

Redox chemistry

In the field of redox chemistry, electrolyte formulations for all-vanadium redox-flow batteries are developed and optimized. In addition, formulations for other flow battery systems are investigated, electrochemically tested and characterized in a cell test. Particular attention is paid to electrolytes for bromine-based and organic redox-flow batteries, as well as vanadium-air systems.

Stack development and battery systems

From the construction of prototype batteries to the development of industrial production processes for battery stacks, Fraunhofer ICT covers every stage in battery production. Tests are also available to certify flow batteries from the stack up to entire battery systems.


To better understand the operational behavior, fluidic, thermal and electrochemical models of redox-flow batteries are created. New sensor technologies such as spatially resolved current density measurements provide insights into the working battery. On a system level we offer storage designs involving a range of technologies, and technical-economic investigations of storage-based energy supply.

Redox-flow application center

© Fraunhofer ICT

In our redox-flow application center we offer the necessary infrastructure to test and characterize RFB modules in a power range of up to several hundred kilowatts.  Separate tank systems also enable the testing of novel electrolytes on a large scale.