Fraunhofer Institute for Electronic Nano SystemsFuel cells represent an attractive approach to achieve a CO2-neutral energy economy. Here, by means of hydrogen, electricity is generated from hydrogen and oxygen; the only remaining product is water. Furthermore, hydrogen can be produced using power from renewable energies. Fuel cell technology is of great interest for use in the field of mobility (trains, trucks and cars). PEMFC (Proton Exchange Membrane Fuel Cell) is one of the major types of fuel cells that offer various advantages, such as high operational efficiency. However, there are still some major challenges. These include a lack of a complete understanding of the interactions of the materials in the catalytic ink, the materials changes in the catalytic layer formation process from the ink as well as high manufacturing costs of the fuel cell and its components and a lack of flexibility with regard to the production of different fuel cell sizes.
The German-Spanish-Czech consortium is aligned along the entire value chain of PEMFC production. The project partners are crucial to successfully work on the proposed highly interdisciplinary project named IMMENSE. They plan to improve the current fuel cell materials by careful materials selection and tailoring the interfaces within the catalytic ink to enable inkjet-printing as digital production technology supplementing the currently used analogous processes.
A fundamental understanding of the involved interfaces (especially of the 3-phase boundary layer) and how they are formed in the production process is crucial. The interactions of the components in the catalyst layer are manifold and based on the individual material components that have to be carefully selected. Furthermore, a building block approach in formulation of the catalytic ink offers the possibility to tune the materials and interfacial properties, while in conventional inks the tailoring options are limited. The following digital inkjet printing technology, enabled by the well-defined catalytic ink, is flexible with respect to the layout of the printed catalyst area and the fuel cell size of the produced PEMFC. It is also able to generate reproducible interfaces in the catalyst coated membrane (CCM) for optimal fuel cell operation and the ink can be placed on the CCM in the most precise and efficient way, avoiding surplus material deposition. Therefore, no more precious and expensive material is lost in any location, where it is not needed.
Thus, the proposed technology enables a higher utilization of catalyst and tremendously improving the economic efficiency of proton-exchange membrane hydrogen fuel cells by simultaneously saving precious resources in the catalytic materials. The development of a technology for a validated, on demand produced PEMFC needs several key steps.
1. Developing a materials, including novel bio-based ionomers, and process toolbox that allows to tune the interfacial properties of the components of the catalytic ink and the resulting electrochemical properties of the catalyst coated membrane.
2. Obtaining more flexibility in design concerning shape and size by inkjet printing enabling short run lengths while reducing manufacturing costs of PEMFC.
3. Detailed experimental characterization and advanced mathematical modelling provide sufficient background knowledge for a well-designed CCM material selection and manufacturing.
4. Production of a short stack fuel cell demonstrator with the new manufacturing technology based on an optimized material system that can be controlled in a working regime of the application in a car that shows similar performance as conventionally produced fuel cells.
All research is within TRL 1 – 5.
By this project, we address SDG 7 (“Affordable and clean energy”) by utilizing green hydrogen as fuel as well as SDG 9 (“Industrial innovation and infrastructure”) by upgrading analogue production technologies by utilizing the digital inkjet printing technology for material deposition.