Freudenberg Sealing advances green hydrogen production

WEINHEIM, Germany—Freudenberg Sealing Technologies has developed elastomeric sealing solutions for electrolyzers that are used for the production of green hydrogen.

In a statement June 29, FST said it applied its expertise in fuel cell sealing solutions in developing the system for electrolyzers, which are being increasingly used to produce hydrogen power from splitting water.

The company is using a portfolio of proprietary rubber-based gasket materials, including EPDM and FKM formulas, to address the performance requirements and electro-chemistries found in different types of electrolyzers.

To produce the system, FST said it over-molded elastomeric gaskets on to composite and metal electrolyzer stack plates in a four-step process.

Stack plates are used to separate the cells in a stack assembly, and a crucial component of the plates are gaskets that prevent the leakage of gas into other parts of the electrolyzer, the company said.

In addition, Freudenberg said it developed material-specific bonding agents that are applied between the gasket and plate materials to ensure the sealing function is optimized.

"As manufacturing industries make strides in moving toward mass green hydrogen production, our ambitious goal is to support demand for high-capacity electrolyzer gaskets by 2023," said Robert Lidster, technical director, gaskets division, Freudenberg Sealing Technologies.

Here, Lidster said FST has tapped into its years of experience in "successfully sealing fuel cell systems."

"While these do not operate at the pressure and temperature extremes found in high-density electrolyzers, they have provided us with a complete understanding of what is required to seal these aggressive environments over a very long lifecycle," he said.

Freudenberg's engineers are currently working on gasket integrated electrolyzer plates for polymer electrolyte membrane (PEM) and alkaline (AEL) electrolyzers.

Due to the differences in the electrolyte materials used in these systems—PEM systems use a solid electrolyte membrane of perfluoro sulfonic acid (PFSA) polymers and AEL systems use a liquid electrolyte solution such as potassium hydroxide or sodium hydroxide and water—FST said its facilities collaborate closely with customers to tailor gasket materials and adhesives for optimal performance in different types of electrolyzer systems.

According to FST, in addition to pressure and temperature concerns, the company's engineers also address issues such as corrosion resistance, stability, material breakdown and permeability in different electrolyzer environments.

"Freudenberg is continuing its pursuit of innovative sealing solutions for more green power and transportation applications and is pursuing other rubber-coated metal components for electrolyzers and other alternate power systems," the company added.

Presently, most hydrogen produced globally uses fossil fuels.

Electrolysis provides a green alternative, using electricity to split water molecules into oxygen and hydrogen gas ions through an electrolyzer system.

The hydrogen ions can be used as hydrogen fuel, or recombined with oxygen to create oxyhydrogen gas, which is used in industrial welding and other applications.

"With ambitious, industrial emissions goals quickly emerging, green hydrogen produced via electrolysis will triple in the years ahead, with the major transition starting in 2030," according to Artur Maehne, global segment manager of hydrogen technologies for Freudenberg Sealing Technologies.

"Many companies are now working on the manufacture of electrolyzers, the core of green hydrogen production. Along with established firms, we are seeing many new companies making their way into the market."

Today, green hydrogen accounts for about 1 gigawatt of power worldwide. Driven by the climate urgency and countries' commitments to net zero, the International Renewable Energy Agency (IRENA) estimates hydrogen to cover up to 12 percent of global energy use by 2050.