With its more than 1,000 staff members Fraunhofer ISE is the largest institute in Europe for applied research and development in the field of solar energy conversion and belongs to the Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. The Division Energy Technology performs research and development on aspects of hydrogen technology and energy storage, comprising hydrogen production by means of reforming and electrolysis, hydrogen storage as well as hydrogen conversion into electrical power and heat by means of fuel cells.
Hydrogen storage systems including PEM water electrolysers for various applications have been designed and built over the last 20 years in Freiburg. Current R&D comprises fundamental investigations of single components, electrochemical characterisation of membrane electrode assemblies (MEA) up to 50 bar, long-term measurements of single cells and stacks, stack design assisted by means of CFD simulation, and development of bipolar plates. System aspects are addressed by the design of balance of plant components and development of control strategies for turn-key electrolysers. Furthermore, hydrogen production has been demonstrated in a PEM electrolysis module directly coupled with a PV concentrator using III-V multi-junction solar cells. Fraunhofer ISE is certified according to DIN ISO 9001.

The main tasks attributed and previous experiences
In the MEGASTACK project, Fraunhofer ISE main objective will be the use of a multiscale modelling approach to develop and experimentally validate mathematical models which will serve as engineering tools for stack design and up-scaling. Our coupled physics model comprising of three main sub models (electrochemical reaction kinetics, mass and momentum transport in porous current collectors and heat and water management) on the cell level and solved using the codes of COMSOL Multiphysics® will serve as input to a two-phase flow model for gas bubble evolution, distribution and movement that will be developed by SINTEF using the ANSYS FLUENT® package. Results from the coupled models will be used for optimized stack design. Simulation results from electrochemical models will be used for determining optimal catalysts specifications. Analytical evaluation and porosimetry characterization of current collectors for flow and microstructure properties will also be performed and used in simulations. This will also serve as input to current collector manufacturer for an optimized porous current collector. Finally, Fraunhofer ISE will provide test facilities and assist in the testing and characterization of single cells and short stacks developed within the project.

The team has comprehensive experience in European projects derived from several collaborative EU research projects of the 5th, 6th and 7th framework programme, e.g. development of reversible fuel cells and hydrogen storage systems, in the just ended FU FCH project NEXPEL as well as lifetime and degradation studies in the on-going FU FCH NOVEL project.