Hydrogen Electrolysers: Plastic Cell Frames for Industrial Hydrogen Productions

Green hydrogen is becoming one of the key technologies for the decarbonisation of industry, energy and mobility. As electrolyser systems move from pilot installations towards industrial production, the demand for scalable, reliable and cost-efficient manufacturing concepts is growing. One component is gaining particular attention: the electrolyser cell frame. For these large, precise and chemically resistant parts, engineering plastics and advanced injection moulding technologies offer promising new opportunities. ENGEL supports this emerging market with machine technology, application know-how and dedicated trial capabilities for the industrialisation of next-generation hydrogen components.

Electrolysers use electrical energy to split water into hydrogen and oxygen. Inside the stack, the cell frame is a key functional component. It supports the overall stack design, contributes to media guidance and sealing, and helps maintain mechanical stability over the lifetime of the system.

Many hydrogen projects are currently moving through an important transition phase: from technical feasibility and prototype production towards repeatable industrial manufacturing. This shift creates new requirements for component design, material selection and process stability.

Injection moulding can play an important role in this transition. Compared with many conventional production routes, it offers high repeatability, design freedom, function integration and the potential for economical series production once volumes increase.

For cell frames, however, successful industrialisation requires more than simply transferring an existing design into an injection mould. Material, part design, mould concept, machine technology and process development must work together from the beginning.

Electrolyser components operate in demanding environments. Depending on the technology, they may be exposed to temperature, pressure, water or alkaline media such as KOH. This makes long-term material performance a central topic.

High-performance thermoplastics such as PPS, PSU, PPSU and PEEK are among the relevant material families being evaluated for hydrogen applications. They offer interesting combinations of temperature resistance, chemical resistance, mechanical performance and processability.

One important engineering topic is the use of glass-fibre reinforcement. In alkaline environments, reinforcing fibres can be attacked by the surrounding media over time. This makes the amount and structure of reinforcement a critical design parameter: if fibres form a continuous path through the part, this can trigger a chain reaction in which the fibres are progressively dissolved, leading to a loss of structural stability over time.

When reinforcement levels and part design are chosen carefully, this effect can be limited to a shallow surface layer, while the core material remains largely unaffected. This balance between mechanical performance and long-term chemical stability is one of the key material challenges in this field.

The right material choice depends on many factors: electrolyser technology, part design, operating conditions, lifetime targets, cost requirements and validation strategy. ENGEL does not define the material alone. Instead, ENGEL works with customers, material specialists and mould makers to help identify a robust and scalable production concept.

The hydrogen market is developing several electrolyser technologies.

PEM - Proton Exchange Membrane Electrolysers are known for dynamic operation and compact system designs. They are particularly relevant where renewable energy input can fluctuate.

AEL - Alkaline Electrolysers are established and robust, especially in larger industrial applications.

AEM - Anion Exchange Membrane Electrolysers are an emerging technology field that combines aspects of membrane-based and alkaline systems and could open up new opportunities for future stack designs.

Each technology brings different requirements for the cell frame, the material and the manufacturing process. This diversity makes the market highly dynamic and creates room for new production concepts based on plastics processing.

Cell frames are not simple plastic parts. They are typically large, flat and function-critical components with high requirements regarding dimensional accuracy, stability and repeatability.

One of the key topics in this field is warpage. For large-format components, even small deviations can influence assembly, sealing behaviour and overall stack performance. This makes process stability and precise control during production essential.

Advanced process technologies such as injection compression moulding, also known as coining, can offer interesting advantages for these types of components. The technology can support improved dimensional stability and can help open new process windows for large, flat parts.

The exact process concept always depends on the part geometry, material and performance requirements. This is why early testing and application development are so important.

A key advantage for customers is ENGEL’s ability to support development through practical trials. In our trial and application centres, customers can work with our experienced application engineers to test materials, moulds, machine concepts and process strategies under realistic production conditions. With machines offering clamping forces of up to 55,000 kN, even large-format electrolyser cell frames can be evaluated close to series-production requirements.

These trials help customers better understand part behaviour, optimise processes and reduce development risks. Especially in hydrogen applications, where cell frames require high quality, repeatability and long-term performance, practical testing provides a solid basis for industrialisation and investment decisions. ENGEL’s trial centres therefore bridge the gap between concept, prototype and series production.

The production of large electrolyser cell frames requires a machine platform that combines stability, precision and process flexibility. ENGEL’s large-machine portfolio provides the foundation for demanding applications where part size, shot weight and dimensional stability are important.

One of the most critical factors for large, flat cell frames is platen parallelism. Even minimal deviations across a large mould surface can lead to uneven wall thickness, increased warpage and inconsistent part quality.

Our duo machine platform offers precise platen parallelism control, with the ability to individually adjust and monitor the tie bars during the process. This level of control is especially valuable for injection compression moulding, where maintaining consistent parallelism throughout the compression movement is essential for repeatable results.

This precise parallelism control is one of ENGEL’s key strengths and a clear differentiator for large-format, high-precision applications such as electrolyser cell frames. Combined with stable plasticising, repeatable injection performance and reliable process monitoring, it forms the technical foundation for consistent part quality over long production runs.

The mould concept has a major influence on the success of any cell frame project. Gating, cooling, venting, part handling and the mechanical stability of the mould all affect the final part quality.

ENGEL supports customers in developing the right overall production concept – from machine technology and process development to integrated ENGEL automation. Depending on the production target, this can include part handling, downstream cooling, quality checks and further automation steps.

For mould-related topics, we can also involve experienced mouldmaking partners where required.

As volumes increase, the focus shifts from producing individual good parts to achieving stable, repeatable and efficient production over long runs. This is where integrated system thinking becomes essential.

Sealing is one of the key functions in an electrolyser stack. Depending on the stack design, cell frames may require several sealing areas around membranes, media channels and external contours.

Today, sealing concepts are often handled in separate production or assembly steps. In future industrial concepts, integrated or automated sealing solutions may become increasingly attractive. These could include post-moulded sealing, automated gasket handling or multi-material approaches.

The right solution depends strongly on the application and must be validated carefully. Material compatibility, process temperature, adhesion and long-term durability are important factors.

ENGEL sees functional integration as one of the important future directions for hydrogen components — not as a standard solution, but as a field with significant development potential.

The hydrogen industry is still evolving rapidly. Many companies are developing new stack designs, testing different materials and preparing for higher production volumes. In this phase, early manufacturing expertise can make a decisive difference.

ENGEL supports customers with:

• application consulting

• machine and process know-how

• trial centre capabilities

• injection compression moulding expertise

• precise platen parallelism control for large-format parts

• large-part injection moulding experience

• automation and system integration

• support from feasibility to series production

For electrolyser cell frames, the key challenge is not only producing the part once. The challenge is developing a scalable, repeatable and economically viable production concept for the future.

Plastic cell frames can become an important enabler for the next generation of hydrogen systems. We are ready to support this development – with technology, experience and practical application support.

Get in touch with us.

Engineering plastics can offer advantages such as weight reduction, corrosion resistance, design freedom and potential for functional integration. As electrolyser production volumes increase, injection moulding can become an attractive route towards scalable manufacturing.

Relevant material families include PPS, PSU, PPSU and PEEK. The final selection depends on the electrolyser technology, operating conditions, part design and validation requirements.

PEM, AEL and AEM are different electrolyser technologies used for hydrogen production. Each technology has different requirements regarding materials, media resistance, component design and manufacturing concept.

Cell frames are large and function-critical components. Dimensional stability and flatness are important for assembly, sealing and stack performance. Therefore, process development plays a key role.

Injection compression moulding, also known as coining, is an advanced injection moulding process that can offer advantages for large, flat and precise components.

For large, flat cell frames, even minimal deviations in platen parallelism can affect wall thickness, warpage and part quality. Precise parallelism control is therefore a key requirement for consistent results, especially in injection compression moulding.

Yes. ENGEL operates trial and application centres where customers can carry out practical tests together with ENGEL experts. These trials can help evaluate materials, tools, machine concepts and process strategies.

Integrated sealing concepts may be possible depending on material combination, part design and application requirements. This is an area with future potential, but it must be validated carefully.

ENGEL supports customers from early feasibility discussions through trials, process development and production concept definition. The focus is on developing scalable and reliable manufacturing solutions.