From element to energy

As the most abundant element in the universe, hydrogen exists in theoretically unlimited quantities, yet its energy is released only through chemical reactions. Produced through electrolysis using renewable energies, green hydrogen plays a pivotal role in driving the energy sector’s successful transition. It functions as a storage medium for renewable energy (power-to-gas), serves as a chemical feedstock, and facilitates the decarbonization of industrial sectors. To date, large-scale production of green hydrogen remains challenging due to high costs, significant energy requirements, and insufficient infrastructure. In an effort to drive technological progress in this field, the ElringKlinger Group is drawing its expertise developed over a period of many years – through its sealing technology and ElringKlinger Kunststofftechnik GmbH as well as in the form of EKPO Fuel Cell Technologies GmbH.

The beating heart of hydrogen

What is now recognized as a key technology for a climate-neutral future had its beginnings at ElringKlinger nearly two decades ago. The company launched its first series project as far back as 2008. Over the years, a broad technological foundation was established, culminating in the formation of EKPO Fuel Cell Technologies in 2021. With co-shareholder OPmobility as a formidable partner, this joint venture unites expertise in developing and producing high-performance fuel cell stacks and central components at industrial scale.

Along the hydrogen value chain, EKPO serves as a key enabler. The company operates at both critical points of the hydrogen cycle. On the one hand, EKPO supplies the heart of every fuel cell: highly efficient PEMFC stack modules that reliably convert hydrogen into electrical energy through an electrochemical reaction and make this energy immediately available for the respective application. Leveraging scalable production lines and extensive expertise in metallic and polymer core technologies, EKPO has established the foundations for industrial-scale fuel cell production. The stacks and components developed by the company are used in a wide variety of applications – including cars, commercial vehicles, buses, rail vehicles, maritime systems, and stationary energy units.

On the other hand, EKPO is also active at the point of green hydrogen production. By producing central components such as the metallic bipolar plate at scale, the company is also capable of serving the upstream segment of the value chain. The company’s high-precision, technologically advanced bipolar plates are employed in high-performance electrolyzers that operate on the PEM electrolysis principle to generate green hydrogen. They ensure that modern electrolyzers are efficient, durable, and scalable at an industrial level, thus creating an important technological basis for a sustainable hydrogen economy.

The pulse of hydrogen technology

As the central “pulse generators” of modern fuel cells and electrolyzers, metallic bipolar plates constitute the functional heart of both systems. Depending on the application, they consist of a thin metal sheet or two very delicate metal sheets welded together. Its surface features microstructured channels – the so-called flow field – through which water, hydrogen, and oxygen are directed with precision. A cooling medium flows between the plates, maintaining the thermal stability of the systems.

The foundation for EKPO’s high-performance bipolar plates was established more than twenty years ago, when ElringKlinger adapted its core technologies associated with cylinder head gaskets to the development of metallic bipolar plates. Drawing on extensive experience in metal forming, advanced joining and coating processes, and precise elastomer sealing technology, traditional expertise in combustion engine sealing was applied to create a highly functional, production-ready core component for fuel cell and hydrogen systems. Today, EKPO produces these bipolar plates through fully automated series processes that integrate complex 3D forming techniques, progressive tooling, and corrosion-stabilizing coatings. A key strength lies in the integrated sealing technology: precisely engineered elastomer-based sealing systems ensure consistently reliable separation of gases and liquids, even under high pressure, fluctuating temperatures, and dynamic loads. Meticulous geometric design and in-house tool development provide the basis for optimal dimensional accuracy and stable production processes. The high-precision bipolar plates form not only the heart of modern fuel cells and electrolyzers but at the same time also serve as the technological foundation for the next stage of the value chain: EKPO’s fully integrated stack platforms.

Technical insights: Green hydrogen
production via electrolysis

As one of the central approaches, electrolysis offers significant potential for generating green hydrogen. In this process, water is split into hydrogen and oxygen using electrical energy. EKPO Fuel Cell Technologies develops scalable, precision-engineered components for modern electrolyzers, the aim being to improve both the efficiency and cost-effectiveness of hydrogen production.

Turning precision into energy

Building on the exceptional precision of its metallic bipolar plates, EKPO develops high-performance stack platforms that facilitate the critical transition from chemical element to usable energy. They bring together all core components – including bipolar plates, MEAs, seals, and compression modules – to form a fully harmonized overall system. In addition to efficiently converting hydrogen into energy, the stacks perform essential functions, including precise gas routing, temperature management, current dissipation, and secure sealing. Thanks to durable materials, a high degree of vertical integration, and smart modular design, EKPO’s stack platforms offer flexible scalability and are well suited for mobility, industrial, and infrastructure applications. As such, they serve as a central link in the hydrogen value chain, transforming molecular elements into usable energy.

The portfolio encompasses four modular stack platforms – NM5 evo, NM12 single, NM12 twin, and NM20 – and covers a power range from 16 to 400 kW. The NM5 stack is used, for example, in forklift trucks or stationary energy supply systems. With its proven durability in fuel cell vehicles, the NM12 stack delivers maximum efficiency, while the NM20 module is EKPO’s most powerful platform at up to 400 kW; the latter receives funding under the IPCEI hydrogen program “Hy2Tech.” Collectively, they play their role in building a high-performance, climate-neutral energy infrastructure for both mobility and stationary use.

Plastic solutions that keep the hydrogen world connected

While large tanks are being filled, electrolyzers are splitting water into pure hydrogen, and fuel cells are generating energy from it, a critical process is occurring in the background: XXL cell gaskets, various insulating components, intricate high-pressure seals, and precision-molded parts engineered by ElringKlinger Kunststofftechnik ensure these operations run reliably and safely. Designed to withstand the severe chemical, thermal, and mechanical conditions associated with state-of-the-art hydrogen technologies, the key polymer components play a pivotal role throughout the hydrogen value chain – from production, cooling, storage, distribution, and transport to purification and utilization. They are deployed wherever metallic materials reach their limits – whether as a component engineered with millimeter-level precision or as a part boasting an impressive three-meter diameter.

High-performance sealing for safe hydrogen production

Electrolysis processes are subject to continuous improvement in support of climate-friendly hydrogen production, the aim being to raise efficiency, safety, and durability levels. Within a modern electrolysis plant, several hundred individual cells operate together in a precisely layered stack. Each of these cells plays a part in splitting the water – and each relies on complete sealing integrity. This is where a key component from ElringKlinger Kunststofftechnik comes into play: the large-format Polytetraflon™ PTFE cell gasket. In alkaline electrolysis, it maintains the reliable separation of the corrosive potassium hydroxide solution and the resulting hydrogen and oxygen gas flows, even when exposed to high pressures and temperatures. ElringKlinger Kunststofftechnik’s specially developed Polytetraflon™ PTFE compounds are used to produce components reaching diameters of up to three meters, depending on the system size; these parts ensure stable operating conditions and, through their high precision, play a key role in optimizing electrolysis efficiency.

This illustrates the close integration of expertise within the Group: while EKPO’s components facilitate the conversion of water into hydrogen or hydrogen into energy, parts supplied by ElringKlinger Kunststofftechnik ensure the reliable operation of the system environment. Together, they establish a coherent technological foundation for the hydrogen economy, thereby enabling the transition “From element to energy” on an industrial scale.

ElringKlinger-products support the entire hydrogen value chain - from production and storage to utilization.

ProEly: Enabling efficiency, scaling electrolysis

The hydrogen economy stands on the cusp of an industrial-scale breakthrough. Through “ProEly,” ElringKlinger is playing a key role in advancing the industrial ramp-up of the hydrogen economy. In the context of this key strategic project, ElringKlinger is partnering with research and industry stakeholders to create recyclable, functionally integrated plastic cell frames for alkaline electrolysis (AEL) that are tailored to the requirements of industrial-scale manufacturing. What may seem like just a single component becomes a key factor in the scalability of electrolysis systems, given the large quantities required. This is because each megawatt of electrolysis capacity requires 200 to 300 cell frames – a scale that can be achieved only through highly automated and efficient manufacturing processes.

In pursuit of this goal, ProEly brings together material-specific innovation and cutting-edge energy technology. The use of high-performance plastics paves the way for lighter, resource-efficient, and recyclable cell frames while ensuring stability under pressure, precise media flow, and dependable sealing. In this way, they serve as a key component that optimizes the system as a whole. These newly developed cell frames provide the basis for more durable, energy-efficient, and economical electrolysis stacks, thereby contributing directly to the national hydrogen strategy and the targeted multi-gigawatt increase in electrolysis capacity by 2030.

ElringKlinger brings its extensive expertise in plastics processing, precision manufacturing, and large-scale production to the ProEly research project, establishing the foundation for the next generation of electrolysis systems. In its role as a key technology partner, the Group is thus bridging the gap between water as an elemental resource and the cost-effective production of green hydrogen – through the development of a crucial component.

Know-how – driving the future

Moving forward in pursuit of a climate-neutral future, ElringKlinger brings together precisely those competencies that are required by a high-performance hydrogen economy: sophisticated knowledge of materials, high precision in metals and plastics processing, and decades of expertise in industrial-scale series production. The expertise cultivated over decades in the automotive industry now underpins the development of innovative, zero-emission technologies. Throughout the hydrogen value chain, ElringKlinger creates solutions focused on improving efficiency, enabling growth at scale, and actively influencing the trajectory toward long-term sustainability.