Stack Scale up – Industrialisation of PEM electrolyzers

For PEM electrolysis, a large market growth is expected worldwide within the next 10 years. PEM EL technology still holds great potentials in terms of plant investment costs (EUR/kW) and lifetime. A reduction larger than 50% is considered one of the main prerequisites for the competitive production of green hydrogen using PEM EL. A significant contribution is attributed to the stack technology, which is the core component of an electrolysis plant. The goal of StacIE is the further development of the stack technology, both on the component level and on the subsystem level, with the objectives of higher efficiency (>75 %), longer lifetime (>80,000 h), lower manufacturing costs, as well as the further development to production processes suitable for large-scale production in terms of sizes and output volume (GW p.a.). Technological development fields in this context are the structuring of the bipolar plate, the production of better porous transport layers (PTLs), catalyst coatings on membrane or PTL, corrosion-resistant protective layers and an automated stack assembly. To this end, a consortium was formed with partners from industry and science at the German site. The partners have proven expertise and resources in elementary areas of stack technology for testing and producing the components - and thus fulfill a key function for a future supply chain in Germany. As a result, this research project will contribute to strengthening the competitiveness of Germany as a location for technology and production of PEM electrolysis stacks and their components. The work at KIT includes experimental investigations and simulations with the aim to increase the performance and stability of the PEMEL stack, i.e. development and application of testing techniques, dynamic measurement methods, physicochemical cell models as well as CFD simulation tools to optimize the bipolar plates.

The work at KIT comprises the development and application of a dynamic electrochemical 0D cell model which is used as a basis for a model-based electrolyzer design. For experimentally supported model development and parameterization, a test bench for the electrochemical characterization of incremental repeat units will be developed and dynamic measurement methods for PEMEL cells will be implemented. Using conventional and newly developed characterization methods, the model structure and associated parameters will be evaluated. The focus is also on the determination of local concentrations via operando mass spectrometric and gas chromatographic analysis techniques. An extended dynamic modeling of nonlinear electrochemical processes in the cell will be performed on the basis of NFRA measurements as well as thermal, chemical and pressure impedance spectroscopy. The 0D cell model will be transferred into a CFD model to be developed within the project.