Deutsche Version  ACT
Electrical Storage
PEM elektrolysis 30.8.2016

PEM electrolysis cell stack made of Plexiglas for demonstration purposes
© Fraunhofer ISE

Put stacks through their paces

Stacks with a capacity of one megawatt class have so far not been

sufficiently investigated. In this project, scientists are developing a

globally unique test center for PEM electrolysers. This stack may soon

be studied for up to 1 MW connected load.

Project status Installation of the system
Project duration October 2012 until June 2017

A unique key feature of the laboratory is the possibility of the development, operation and characterization of PEM electrolysis stacks with a nominal power input of up to 1 MW. Globally, there is no research institution or company that can study stacks in this power class. The core of the development and technology center is a test bench for characterizing PEM electrolysis stacks with a 1 MW power supply, a maximum electrical current of 4000 A and a maximum stack voltage of 250 V. The maximum hydrogen output is specified with 200 Nm³/h. This structure is accompanied by a short stack test bench with a power of 200 kW, which will allow measurements with special diagnostics of electrolysis stacks with a reduced number of cells.

The overall objective of the project is therefore to provide the German development landscape a powerful test environment that enables service measurements for the industry that are unique in the world.

  • Test center in the north of Freiburg © Fraunhofer ISE
  • Comparison of different energy storage technologies in relation to power an energy in double logarithmic scale © Fraunhofer ISE
  • PEM Elektrolysis cell stack build at Fraunhofer ISE © Fraunhofer ISE
  • PEM electrolysis cell stack made of Plexiglas for demonstration purposes © Fraunhofer ISE
  • Cell stack build at Fraunhofer ISE © Fraunhofer ISE
  • Thermal image during operation recorded with an infra-red camera © Fraunhofer ISE

The research focus is on the following aspects:

  • A 1 MW test bench for short and long-term characterization of pressurized PEM electrolysis cell stacks (up to 4.000 A and 250 V)
  • A 200 kW test bench for long-term characterization of pressurized PEM  electrolysis cell stacks (up to 30 cells and 4.000 A) to evaluate long-term effects
  • A master control room to integrate electrolysers into the electrical power grid and safely control the test benches
  • A hydrogen storage device including processing and compression of produced hydrogen to further utulization in other processes or in power-to-gas applications
  • Various analytical methods for investigating the produced gases (mobile gas analysis) and the materials used (imaging method for 2D and 3D analysis of porous cellular materials such as computed tomography and elemental analysis as EDX)
  • A stack assembly laboratory with various tools and material preparation
  • A powerful simulation environment for electrochemical modeling of electrolysis cells and simulation-based design of PEM electrolysis stack, including the necessary licenses for the simulation tools (e.g. COMSOL, Matlab-Simulink).

In five stations to the final test center

The project is currently in the second phase in which the planning of the laboratory setup is complete. Various equipment has been procured and installed. Other equipment will be purchased in the near future.

Phase 1: A concept for the equipment of the PEM electrolysis test laboratories is prepared. This includes a design for the infrastrutcture in terms of electrical power, gas distribution and security monitoring. Several technical specifications for the equipment will be written. The workshop and scientific workstations will be equipped.
Phase 2: In this phase, the hardware will be procured in accordance with the procurement regulation. For the procurement, initially a search of equipment and suppliers is carried out and then the technical specifications are discussed. After that, the procurement is mostly done in tendering procedures.
Phase 3: In the next phase, the hardware installation is carried out in the laboratory. After installation, the equipment will be connected to the existing infrastructure of the laboratory (air, water, gases, etc.).
Phase 4: In this phase, the equipment will be taken in operation and final adjustments will be made. An important issue is the review of the safety technology. The devices are subsequently connected to the master control room.
Phase 5: A trial run of the test laboratory will follow. A 1 MW and a 200 kW test bench are the main elements of the test center. Defects will be eliminated. Secure processes and test procedures will be developed.

Hydrogen technology at Fraunhofer ISE

In the area  of business "Hydrogen Technology" the possibilities of hydrogen production, storage and power generation in fuel cells are studied intensively. The area includes about 70 scientists and engineers on the topics of electrolysis, solar hydrogen, PEM fuel cells, redox flow batteries, biomass conversion and reforming.

Starting with the energy self-sufficient solar house in Freiburg, PEM electrolysis systems are developed and optimized at the Institute for over 20 years, taking systemic considerations to store hydrogen into account. Thus, the Fraunhofer ISE is the only research institute that continuously works on the development of the PEM electrolysis for 20 years. In the late 1990s Fraunhofer ISE has build a solar hydrogen station on the basis of PEM electrolysis. This project was subject to confidentiality, as well as the individually constructed and highway code approved hydrogen vehicle. In the meantime, numerous development projects for PEM electrolysis were driven with different objectives. Just recently the institute has opened an officially accessible solar hydrogen station for refueling of 700 bar pressure tanks. The hydrogen is produced on-site by a pressurized PEM electrolyser , which is supplied with electricity by photovoltaic modules. Together with two fuel cell vehicles (Daimler F-Cell B-Class), the user behavior and the everyday applicability of a hydrogen- based mobility are investigated.

Due to the need for energy policy action, Fraunhofer ISE is also involved in several projects that are dedicated to the development of large electrolysis cell stacks and the power-to-gas issues in the MW class. To accompany these projects scientificly, there is a necessity of a test and development center for the PEM electrolysis.

Supported by: The Federal Government on the basis of a decision by the German Bundestag


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Research funding

The information system EnArgus provides information on research funding, including on this project (German only).