Realistically depicting processes in the fuel cell
In the transport sector, drive concepts are moving from conventional internal combustion engines to zero-emissions electric drives. All modes of transport are affected, whether it be cars, buses, trucks, trains, ships, or airplanes, and whether it be private, public, or goods transport. Fuel cells will be an important drive form in future. In particular, the benefits of the short refuelling times and the high energy storage density, which result in long ranges, will catch on for long-distance vehicles, buses, and trucks.
The first small-scale production vehicles, the Daimler GLC, the Toyota Mirai, the Hyundai ix35 fcell and NEXO, and the Honda Clarity, are already on the market. Alstom has put the first fuel cell-powered train in Germany into service. Nikola and Hyundai have announced fuel cell-powered trucks to go on sale in Switzerland in the near future. Daimler, Solaris, Van Hool, and Wright are developing fuel cell-powered buses.
Constant further development of new materials and production processes for fuel cells is gradually increasing their power density. This is also resulting in new challenges for operating fuel cell systems, such as water and heat management.
Comprehensive analyses of the properties of new materials and their compatibility in the layer structure of the membrane electrode assembly are essential and require complex transport and reaction models to be continuously improved. Reducing the amount of expensive materials, such as the noble metal catalysts in the electrode or the proton-conducting electrolyte membrane, leads to thinner layers of these materials and makes their interaction with each other more sensitive to the processes taking place in the fuel cell. Interface effects play a greater and greater role in the transport properties of the new materials.
The scientists in the FC-CAT FUEL CELL CFD AND THROUGH-PLANE MODELLING project coordinated by the Fraunhofer Institute for Solar Energy Systems (ISE) analyse and describe the functional layers of the fuel cell with new materials using experimental characterization and theoretical work. One of the focuses is on developing time-dependent models to describe spatially dynamic processes that can be used to analyse locally measured impedance spectra. The researchers are upgrading an existing stationary 3D model to produce an improved realistic depiction of the electrode processes.
The project also aims to support the fuel cell industry by developing a reliable and comprehensive basis for (flow) modelling of fuel cells and making this available to the expert community. This will improve the international competitiveness of the German supplier industry in particular.
The long-standing Canadian–German cooperation agreement on fuel cell research is being continued. The research project builds on the results and analyses of the performance-determining effects of PEM fuel cells, which have been funded since 2009 by the Federal Ministry of Education and Research. The PEM-CaD, GECKO, and DEKADE projects have established cooperative ties with Canadian fuel cell science that will last for ten years. Canada is one of the leading countries in relation to PEM fuel cell research and is home to several world-class companies from the fuel cell industry.