Fuel Cell Test Center: Fuel Cell Testing at the ZSW in Ulm

Since its foundation in 2001, the Fuel Cell Test Center of the Zentrum für Sonnenenergie und Wasserstoff-Forschung Baden-Württemberg (ZSW) in Ulm has established itself as one of the world's leading fuel cell test centers.

In order to be prepared for future market developments, the ZSW has continuously expanded its fuel cell test stations. Today, the institute operates one of the world's largest independent fuel cell stack test facilities with approximately 50 fully automated test benches ranging from a few watts to 250 kilowatts electrical power.


Dr. Alexander Kabza
+49 731 9530-832
Fuel Cell Stack Testing, modern fuel cell test center at ZSW in Ulm, Germany
Fuel cell test bench: Fully automated test benches for fuel cells enable 24/7 operation

What we need to for successful fuel cell product development?

First of all, in generally words:

  • A well-developed supply industry for stack materials and systems components
  • Smart people developing fuel cell stacks and systems
  • And lots of testing with the final stack design (large scale, full active area)!

What you need to get reliable, robust, high quality test results

  • Well engineered (or industrialized) fuel cell stacks and systems
  • High quality fuel cell test benches and a powerful (real-time) data management
  • Robust test infrastructure with H2 supply, compressed air and pure water (with a perfect reactant quality)

Where ZSW can support these activities

Fuel Cell Testing Station and Fuel Cell Test Equipment

As fuel cell systems for mobility and stationary applications continue to enter the global marketplace, the need for testing and characterization increases. And with it, the need for independent test facilities.

Fuel cell test station: ZSW has many years of experience in the development and construction of fuel cell test benches for standard and special applications. For 25 years, our test benches are controlled by our own proven and user-friendly control software with integrated data acquisition.

A fuel cell test bench at ZSW enables cost-effective continuous testing around the clock (24/7), using various AI methods to evaluate the measured data, too.

View of the new test center at HyFaB: Extensive test procedures help optimize fuel cells for different applications

Thanks to the comprehensive test procedures and the various test stations at ZSW, companies and research institutions get access to a wide range of services to optimize their fuel cell applications and increase their performance.

For the automotive industry, the ZSW offers a sought-after test facility and test equipment for fuel cells. The focus is on testing fuel cells in road traffic. Special attention is paid to the electrical behavior of the fuel cell under dynamic load conditions as they occur in everyday driving.

In addition, fuel cell modules with hydrogen or hydrogen mixtures in the power range from 100 W to 100 kWel are tested at ZSW for their suitability.

The Importance of Fuel Cell Stack Testing

Fuel cell stack testing plays a critical role in fuel cell quality assurance and performance optimization. By testing and characterizing fuel cell stacks, manufacturers and research institutions can ensure and further improve the reliability, efficiency and lifetime of their products.

Comprehensive test procedures and more than 20 years of testing experience enable us to identify weak points and areas for improvement within the fuel cell stack. This is particularly important because fuel cells can be used in a variety of applications, including mobility, stationary energy storage, and emergency power. In all of these applications, high performance, durability and safety are critical to the success and acceptance of the technology.


Dr. Ludwig Jörissen
+49 731 95 30-605

Services for research partners and industrial companies in the field of fuel cell testing

By offering an independent and comprehensive range of fuel cell testing services, the ZSW provides valuable services and cooperation opportunities for industrial companies and research institutions.

Through cooperation with ZSW, you have access to the team's extensive know-how in the field of fuel cell technology:

  • Test stations and test procedures: For testing fuel cell stacks and modules, ZSW operates state-of-the-art test benches and extensive test procedures. The test benches can be used for 24/7 life tests, load tests and tests under different operating conditions.
  • Research and Development Projects: The ZSW offers research partners and industrial companies the opportunity to jointly realize innovative research and development projects in the field of fuel cell technology.
  • Consulting and expertise: ZSW offers companies and research institutions technical expertise in the field of fuel cell technology. This includes, for example, the design of fuel cell stacks and systems.
  • Continuing education: ZSW offers training courses on various topics related to fuel cell technology.

Fuel Cell Testing Station: Services of the ZSW in Ulm

The ZSW in Ulm offers comprehensive services in the field of fuel cell testing. The focus is on professional endurance testing of fuel cell stacks, systems and system components. The tests provide data for the evaluation of aging, lifetime and robustness.

The test engineers and scientists at ZSW have decades of experience in the field of fuel cell testing and have already tested several hundred stacks. The test data archive now comprises more than 600,000 operating hours (as of 12/2022). The evaluation is performed using extensive analysis and complex failure analysis methods, including AI-based methods.

The industrialization of fuel cells has already led to a record year at the ZSW fuel cell test field in 2020, with more than 100,000 hours of stack testing and a hydrogen turnover of more than 317,000 cubic meters, which corresponds to almost 27 tons.

ZSW's test centers test fuel cell stacks ranging from a few watts to 250 kWel, including full-size automotive stacks and systems & AutoStack industry.

The staff at ZSW can draw on many years of experience in dealing with fuel cell test stands.
The test engineers and scientists at ZSW have many years of experience in the field of fuel cell testing
[Translate to Englisch:] Lebensdaueruntersuchung mit dynamischen Lastzyklus FC-DLC

Fuel Cell Testing - Qualified Testing of Fuel Cells, Stacks, Systems and System Components

At the ZSW

  • Fuel Cells
  • Fuel Cell Stacks
  • Fuel Cell Systems
  • Fuel Cell System Components

are professionally, reliably and robustly investigated and characterized, including qualified test analysis and identification of optimization parameters.

The collected test data is also used for the development of our own advanced system models. Existing implementations of open-source models are being further developed as part of our scientific work to optimize the design and operating strategies of fuel cell systems for a wide range of future applications.

Fully automated, our test benches can be operated 24/7 and are highly flexible, so that almost all customer requirements can be satisfied.

Tests according to specified procedures such as DIN IEC 62282-2 can be performed with the involvement of an Authorized Inspection Agency (ZÜS). A wide range of analytical equipment and methods as well as simulation techniques accompany the tests, as the interpretation of the test results requires a deep understanding of the interaction of the materials and components in the cells.

All test benches at ZSW are fully calibrated with our own calibration standards before and, if required, during a test. If desired, the calibration can be verified on site by an accredited test center (ZÜS), e.g. TÜV. The high flexibility of the test center is achieved by its own control program and workshops, which can also quickly implement customer-specific requirements that cannot be realized with classic commercial test benches.

The test center at ZSW performs all tests according to DIN EN 62282-2 for fuel cells up to 250 kW.

Accelerated aging tests are performed to better understand and evaluate aging processes. At ZSW, these are offered according to DoE (U.S. Department of Energy) - or according customized definitions.

Fuel cell stack in the test stand

The professional evaluation of the test data provides important information for a better understanding, optimization and further development of products or for ensuring their safety - if desired also with external certification. If required, the evaluations are supported by accompanying simulations or in-situ or post-mortem analyses using a comprehensive range of equipment.

Here is an overview of all the advantages of the Fuel Cell Test Center at ZSW:

  1. Cost-effective 24/7 endurance testing
  2. Reliable measurement results
  3. Very high flexibility
  4. DIN IEC 62282-2 compliant
  5. Accelerated aging tests
  6. Professional analysis of test data

Confidentiality is a top priority at ZSW to ensure that sensitive measurement data is kept confidential.

AI-based monitoring of fuel cell tests

The AI experts at ZSW have developed a novel monitoring of fuel cell test stands with the help of artificial intelligence (AI). On the one hand, this checks the plausibility of the operating conditions set on the test bench, thus ensuring that the measurements are carried out under the specified operating conditions and are usable. Monitoring the operating conditions is a first and important monitoring step, as it allows failures caused by the test bench to be detected early and reliably. The cyclic operation of durability tests compares the set operating conditions at a load point with the past operating conditions of the load point. In this example (Fig. 1), due to the commissioning of a neighboring test bench, there was not enough cooling power available, causing the coolant inlet temperature to rise. The algorithm therefore classifies these outliers as anomalies.

Digital Twins for Fuel Cell Stack Characterization

In addition to the operating conditions, the fuel cell stack also needs to be monitored. The monitoring is done with the help of a digital twin (Fig. 2). Based on the current and past operating conditions of the fuel cell stack, this twin calculates a probabilistic prediction of the stack's current cell voltage. Measurement and prediction deviations that are excessive indicate a problem with the fuel cell stack. Figure 3 shows such a case where, after 2700 hours of operation, the cell voltage of the stack dropped abnormally due to an incident. As a result, the deviation between prediction and measurements increases above the classification threshold, causing more measurement points to be classified as abnormal.

After successfully testing this AI-based monitoring, the next step is to automate the algorithms so that the measurements generated on the test benches can be checked for plausibility in real time.

Fig. 1: Deviations in the coolant inlet temperature can be reliably detected using the mean value and 3-sigma interval.
Fig. 1: Deviations in the coolant inlet temperature can be reliably detected using the mean value and 3-sigma interval.
Fig. 2: The fuel cell stack status is monitored with the help of a digital twin.
Fig. 2: The fuel cell stack status is monitored with the help of a digital twin.
Fig. 3: Comparison between model prediction and measurement. Just a short time after the red marked incident the limit is exceeded and all following measurements are classified as abnormal.
Fig. 3: Comparison between model prediction and measurement. Just a short time after the red marked incident the limit is exceeded and all following measurements are classified as abnormal.

Fuel Cell Stack Leak Test and its Importance

Fuel cell stack leak testing is a critical step in ensuring fuel cell quality and performance. This testing helps to identify potential leaks and leakage that could affect fuel cell efficiency and lifetime.

Leak testing is important for the following reasons:

Good fuel cell tightness is necessary to ensure an optimal ratio of fuel and oxidant in the reaction chamber. Leaks can result in reduced efficiency and uneven distribution of reaction gases.

Good sealing extends the life of the fuel cell by preventing unwanted gases or moisture from entering the cell and causing corrosion or material failure.

Construction of fuel cell test benches and fuel cell test equipment at ZSW

The testing and further development of fuel cells and their components requires a reliable and qualified test environment.

The ZSW in Ulm uses special fuel cell testing procedure and test equipment for testing fuel cells in order to perform qualified analysis and to identify optimization potentials.

Since the processes in fuel cells are very complex and cause and effect can rarely be clearly assigned, reliable measurement methods and experienced scientists and engineers are required.

  • Calibration: Complete calibration of the test benches with our own calibration equipment before the start of the tests and, if necessary, also during the test campaigns in order to guarantee unrestrictedly reliable measured values.
  • Expertise: Team of scientists and engineers with ten to twenty years of experience in testing fuel cells.
  • A fast and professional evaluation of the test data with well-founded analysis that help customers to better understand, optimize or prove the safety of products.
  • Comprehensive and modern equipment for advanced in-situ or post-mortem investigations of cells and cell components.
At HyFaB, fuel cell stacks, systems and system components are tested and further developed fully automatically.
State-of-the-art test benches in the HyFaB at the ZSW in Ulm

PEM Fuel Cell Testing and Diagnosis

Since the introduction of PEM fuel cell stacks to the market, ZSW offers PEM fuel cell test and PEM test benches. In the European joint project "Stacktest", coordinated by ZSW and involving eleven partners from industry and research, different test programs for the characterization of fuel cell stacks are defined and validated.

To do this, we are developing test modules and test programs which will be practically tested with hardware from various manufacturers. To evaluate the service life of a fuel cell stack, a current profile was defined that is typical for automotive applications.

As part of the project, further test programs for specific performance data and for sensitivity investigations of various operating parameters, service life and safety aspects were developed and successfully tested at the involved partner institutes. The validation of the test procedures was carried out at the ZSW fuel cell test center with state-of-the-art and reliable test infrastructure

HyFaB - State-of-the-art Fuel Cell Test Center

With the construction of the new HyFaB, ZSW offers one of the most modern fuel cell test centers worldwide. HyFaB was developed for professional research and development of fuel cell stacks, systems and system components.

High number of test stations: With a total of 50 fully automated fuel cell test stations, the HyFaB platform offers extensive test capacities for fuel cell stacks and systems of different power classes.

High power class: HyFaB test stations can test fuel cells up to 250 kilowatts, covering a wide range of applications and technologies.

Fully automated operation: Test benches at HyFaB operate fully automatically and can be run 24/7, enabling efficient and continuous data acquisition.

Wide range of applications: HyFaB platform enables companies and research institutions to test and further develop PEM fuel cell technology for various applications, from stationary applications to electromobility.

Providing state-of-the-art testing infrastructure, ZSW supports the deployment of fuel cells for various applications and promotes the further development of the technology for a sustainable and low-emission energy supply.

This Website uses cookies and third-party content

On this website, we use cookies which are absolutely necessary for displaying its content. If you click on “Accept cookies chosen”, only these necessary cookies are used. Other cookies and content by third parties (such as YouTube videos or maps by Google Maps) are only set with your consent by choosing “Accept all cookies”. For further information, please refer to our data protection policy where you can withdraw your consent at any time.