Hydrogen technology plays a significant role in the energy transition. The leak tightness of fuel cells and electrolyzers is a crucial success factor for their safety and efficiency. As a leading provider of leak testing technology and a long-standing development partner of numerous automotive manufacturers, we offer innovative testing systems for bipolar plates, fuel cell stacks, fuel cell systems, and electrolyzers.

Leak testing of fuel cells
Leak testing with a passion for cutting-edge technology: ZELTWANGER develops advanced testing solutions using air and trace gases at any level of automation.

Application examples

Bipolar Plates

Bipolar plates

Small volumes, minimal leakage rates to be detected and a large number of cavities to be tested are among the challenges in leak testing of bipolar plates. By incorporating sophisticated techniques such as the use of the relative pressure method in conjunction with an external valve block or integrated vacuum testing with tracer gases, we are able to ensure reliable test results.

Fuel cell stacks

Fuel cell stacks have to be highly leak-proof. In order to reliably test these complex systems, various testing methods such as air mass flow are used. To locate leaks with pinpoint accuracy and to ensure a high degree of reproducibility, precisely guided sniffer tests using tracer gases like Helium are applied. Furthermore, we can implement additional steps such as compressing the stacks and marking detected leaks.

Fuel Cell Stacks
fuel cell systems

Leak testing of fuel cell systems

In fuel cell systems, the leak testing of components such as hydrogen supply lines, air and oxygen supply lines, and cooling and heat exchangers is crucial. Ensuring the tightness of these components is of essential importance to guarantee the safety, efficiency, and performance of the fuel cell system.

German Fuel Cell Cooperation

We are a member of the German Fuel Cell Cooperation, your partners for manufacturing equipment from metal strip to fuel cell or electrolyzer stack.

How do you efficiently produce the fuel cell or electrolyzer of the future? VON ARDENNE, Weil Technology and ZELTWANGER have asked themselves this question together. Benefit from the knowledge and expertise of the three companies at every step in the process chain.

Discover professional leak testing 

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Holistic leak testing

We are your partner in all aspects of leak testing.


At ZELTWANGER, all design, development, software and assembly is performed in-house. This allows us to ensure all testers are build to the highest standards in quality and technology.


Thanks to a modular structure and customizable software, our solutions can be tailored precisely to your requirements. In addition, we build custom-fit adaptations for your test objects.


Together with you, we determine the appropriate test methods and carry out feasibility studies if required. Our training courses enable employees to successfully handle the test methods.


We provide support during commissioning. Our technical support, regular calibrations according to ISO 17025 and our spare parts service ensure the accuracy and reliability of your equipment.