DTU Energy Conversion is part of PROSOFC, an EU-funded research project, which aims to find a way to produce more reliable fuel cells. PROSOFC has a budget of 7.35 million euro (54.9 million D.dk.)
The EU-funded project PROSOFC - Production and Reliability Oriented SOFC Cell and Stack Design - is a new three-year research collaboration between DTU Energy Conversion, Forschungszentrum Jülich, Imperial College of Science, Karlsruher Institut für Technologie, Joint Research Centre (European Commission), Topsoe Fuel Cells and two Austrian companies AVL and DYNARDO, which aims to improve the reliability of fuel cells by improving the robustness, manufacturability, efficiency and cost of Fuel Cells state-of-the-art SOFC stacks so as to reach market entry requirements.
The key issues are the mechanical robustness of solid oxide fuel cells (SOFCs), and the delicate interplay between cell properties, stack design, and operating conditions of the SOFC stack.
"We let the mechanics, whether it is durable or not, come into focus"
Seniorresearcher Henrik Lund Frandsen
PROSOFC is a continuation of the on-going collaboration between Topsoe Fuel Cell A/S (TOFC) and DTU Energy Conversion on the development of SOFC, now with European partners.
Focus on the mechanics
The novelty of the project lies in combining state of the art methodologies for cost-optimal reliability-based design (COPRD) with actual production optimization. To achieve the COPRD beyond state of the art, multi-physical modelling concepts must be developed and validated for significantly improved understanding of the production and operation of SOFC stacks. As an example: Field tests of SOFC stacks have shown that there is a difference between real life conditions and test in laboratories.
"In the laboratory the stacks are located in furnaces with good thermal conditions, which ensure a uniform temperature distribution. In the field the SOFC stacks are isolated, making way for an entirely different thermal influence leading to colder edges along the stack when compared to the laboratory," says senior researcher Henrik Lund Frandsen, heading DTU Energy Conversions contribution to PROSOFC.
The temperature differences between cold edges and a warm centre of the SOFC-stacks leads to higher risk of internal tensions and thus the risk of cracks appearing in the weakest cell of the stack. Cracks decrease the performance of a cell and can ultimately destroy it, lowering the performance of the entire SOFC stack.
The key to understanding this process is through validating experiments and models on multiple scales of the SOFC system and introduction of extensive test programs specified by the COPRD methodology.
"We let the mechanics, whether it is durable or not, come into focus," says Henrik Lund Frandsen.
3D modelling of 300 SOFC stacks
One method is 3D modelling of SOFC stacks down to the microstructural level; using advanced computer programs to simulate tests of up to e.g. 300 SOFC-stacks by changing the parameters and testing their impact on the SOFC stacks, before recreating the experiment in reality, when computer simulations have found the right conditions. A hugely cost-effective way of testing compared to testing individual stacks.
Austrian AVL, one of the world's leading companies in testing exhaust pipe and car engines, are leaders of the PROSOFC team to ensure, that the results can in fact be used. AVL is used by most European car companies to reality test the technology in new engines; just like PROSOFC intend to do with the SOFC stacks.
"It is yet to be seen whether we can achieve the desired higher reliability, but we have set the right course. Now we just have to make it work as well in reality as in the laboratories," says senior scientist Henrik Lund Frandsen from DTU Energy Conversion.
PROSOFC terminates in the spring 2016.
For more information contact Senior Researcher Henrik Lund Frandsen, +45 4677 5668, hlfr@dtu.dk