Hydrogen technologies – Plastics and their potential in the hydrogen industry

Connecting hydrogen economy and plastics industry:

With its "Hydrogen Business and Technology Forum", which took off in March 2023, the Institute for Plastics Processing (IKV) in Industry and Craft at RWTH Aachen University has established a close network between the hydrogen economy and the plastics industry, where it regularly fosters the connection of requirements and application know-how with material and production know-how.

The „Hydrogen Business and Technology Forum“ originates from a study titled "Opportunities for Material Technologies in a Hydrogen Economy", in which IKV has compiled application opportunities for plastics along the entire value chain of a future hydrogen economy over the course of a year starting 2021. The study looks at markets from suppliers to end users and systematically analyses the most relevant hydrogen technologies according to the system breakdown method. From this, the need for research is derived and the development of the plastics market resulting from the emerging hydrogen economy is forecast. More than 20 industry partners were involved in the study alone.

With regular workshops and continuous market and technology monitoring, the IKV is now continuing the work in the "Hydrogen Business and Technology Forum". The kick-off for the Forum was 16 May 2023. From now on, representatives of both industries will meet every six months in Aachen to discuss challenges and trends. In addition to the professional exchange, this Forum offers an ideal platform for networking. Besides, Forum members also meet outside the regular schedule for workshops at which individual members take on the role of host. This summer, for example, Freudenberg FTI welcomed Forum members to discuss the challenges of testing and analysing plastics in hydrogen applications.

The hydrogen study and the activities of the “Hydrogen Business and Technology Forum” have already resulted in a first research project: in November 2023, the Poly-H2-Pipe research project, funded with 1.6 million EUR, will start. Together with two project partners, the Welding and Joining Institute (ISF) of RWTH Aachen University and the German Federal Institute for Materials Research (Bundesanstalt für Materialforschung BAM), IKV will look into the design of continuous fibre-reinforced pipe systems for the system periphery of electrolysers or fuel cells.

Successful research for Type IV pressure vessels:

The IKV has started researching alternative materials and manufacturing processes in the production of Type IV pressure vessels for hydrogen storage in the DELFIN project, funded by the German Federal Ministry of Transport and Digital Infrastructure (BMVI) in 2018. These pressure vessels consist of an inner thermoplastic liner for sealing and a sheath wound from carbon fibre reinforced plastics (CFRP) for load bearing. As part of the research project, IKV has developed an optical measurement methodology and adapted image processing algorithms for in-line quality monitoring of the winding process in order to quantify process-related deviations of the sliver deposition, to generate a digital twin and to use this for the realistic mapping of the pressure vessels in the design.

Following the successful completion of the DELFIN research project and the follow-up project DELFIN2, research on Type IV pressure vessels made of CFRP is now being continued. The approach of IKV is to identify the influences of various boundary conditions and errors from the manufacturing process on the component quality and to evaluate the functionality of the components. In order to optimally link the data with the process and make the most use of it, the entire process is mapped via a digital twin.

In the summer of 2023, the DAVID research project (Digitale Auslegungsmethoden von inline-überwachten Druckbehältern, Digital design methods of in-line monitored pressure vessels) was launched. The consortium project, initiated by the IKV as a successor project to DELFIN, brings together a total of ten partners from industry and research (German Federal Institute for Materials Research (Bundesanstalt für Materialforschung BAM, Elkamet Kunststofftechnik GmbH, Envalior GmbH, FORWARD ENGINEERING GmbH, FORM+TEST Seidner & Co. GmbH, ISATEC GmbH, NPROXX Jülich GmbH, Westlake Epoxy GmbH, Teijin Carbon Europe GmbH), with the IKV as the consortium leader. DAVID is funded with 6.3 million EUR by the German Bundesministerium für Wirtschaft und Klimaschutz (BMWK) as part of the program “CO₂ savings through resource efficiency and substitution“ from the Technology Transfer Program Lightweight Construction (TTP LB).

With DAVID, a CO₂ saving of 21 % CO₂-eq per container is to be achieved through resource efficiency and substitution during production. To this end, new end-to-end digital design methods and in-line quality assurance measures will be applied and new adapted material compositions (towpregs) and processing technologies will be used. The technological objective of the current research project is to obtain a realistic description of the vessel materials and the entire system during manufacture and product lifecycle by means of integrated digitalisation and application-specific characterization and modeling. The interactions within the Machine-Process-Material-Morphology-Property relationship will be analysed experimentally and simulatively, and will be modeled with suitable methods and made usable for optimisations in the form of digital twins of the manufactured pressure vessels. The IKV wants to develop and commission a triaxial test stand with hydrogen as the pressure medium in order to be able to carry out application-oriented material tests on thermoplastics, fibre composite plastics as well as elastomers. This will open up completely new possibilities for materials testing, which can serve as a basis for the development of material models for the hydrogen industry.

Low-maintenance mobile high-pressure storage tanks:

Closely linked to the DAVID project is the HyInnoTank project (Low-maintenance mobile high-pressure storage), which runs in three phases of three years each from 2021 to 2030. The project is funded within the context of the Future Hydrogen Cluster of the German Federal Ministry of Education and Research (BMBF) with 2.2 million EUR in the first two phases. The project will develop a methodology for instrumenting Type IV pressure vessels with sensor fibres for strain field monitoring. Through the sensor system, which is permanently embedded in the tank, its structural integrity is monitored in the assembled state, which significantly reduces maintenance costs and downtimes. A knowledge of the local strains at various positions of the pressure tank within the laminate provides information on the material behaviour in different load scenarios, and is thus an important added value for the tank design. This technology will be intelligently coupled with acoustic emission analysis to provide a holistic assessment of the vessel structure and achieve Structural Health Monitoring Level five. Another aim of the project is to develop a model to estimate the residual bursting pressure and residual life expectancy of pressure tanks based on the sensor signal after their typical working life of 20 years, as a result of which options can be derived for further use of the tanks.(Second Life Approach).

Consortinal partners of the HyInnoTank project are: Institut für Textiltechnik der RWTH Aachen University (ITA), NPROXX GmbH, F. A. Kümpers GmbH & Co.KG, ISATEC GmbH, Institut für Strahlantriebe und Turboarbeitsmaschinen (IST) der RWTH Aachen University and Vallen Systeme GmbH.

H₂ permeation test station at IKV:

For about a year now, the Plasma and Surface Technology working group has been working on the development of test station for determining H₂ permeation through any desired sample geometry. Here the IKV has made use of its years of experience in the field of O₂ and H₂O permeation measurement with commercially available measuring devices and has expanded this portfolio for a cooperation with an industrial partner. Since the set-up was developed entirely at the IKV, the IKV is able to respond flexibly to a wide range of measurement requirements. Currently, measurements are possible at pressures up to 16 bar and ambient temperature. With the appropriate adaptation, other conditions can also be implemented – according to the requirements of project partners and customers. The gas composition is determined by mass spectrometry, so that gas mixtures can also be tested. The measuring stand is now being used in various research projects and is also available to cooperation partners from industry upon request.

Hydrogen at the 32^nd International Colloquium Plastics Technology:

At the colloquium Session 9 (Structural health monitoring of hydrogen pressure tanks) will focus on the topic of hydrogen with a keynote speech from industry and two scientific presentations from the IKV.

As part of IKV 360° – Research live, scientific staff will explain the current research approaches on the topic of hydrogen at various stations in the IKV technical centre and will be available for discussions.