By bonding its sealing materials to electrolyser stack plates, the company now offers customers plate units designed to optimize sealing performance in aggressive electrolyser environments.
Freudenberg’s sealing experts have taken the lead in producing elastomeric gaskets that are overmoulded on to composite and metal electrolyser stack plates in a four-step process. Stack plates are used to separate the cells in a stack assembly; a crucial component of the plates are gaskets which prevent the leakage of gas into other parts of the electrolyser. The company is using a portfolio of proprietary rubber-based gasket materials, including EPDM and FKM formulas, to address the unique performance requirements and electro-chemistries found in different types of electrolysers. In addition, Freudenberg has developed material-specific bonding agents that are applied between the gasket and plate materials to ensure the sealing function is optimized.
Extensive material testing, along with advanced injection molding techniques, enable the company to produce high-quality, electrolyser gasket-plate units that are easily transported to, and installed at, customers’ production sites.
Freudenberg’s engineers are currently working on gasket integrated electrolyser plates for polymer electrolyte membrane (PEM) and alkaline (AEL) electrolysers. Due to the differences in the electrolyte materials used in these systems – PEM systems use a solid electrolyte membrane of perfluorosulfonic acid (PFSA) polymers, and AEL systems use a liquid electrolyte solution such as potassium hydroxide or sodium hydroxide and water -- the facilities collaborate closely with customers to tailor gasket materials and adhesives for optimal performance in different types of electrolyser systems.
Concerns about pressure and temperature are not the only performance measures the engineers consider: corrosion resistance, stability, material breakdown and permeability are also closely matched to different electrolyser environments. Here too, the sealing manufacturers’ fuel cell expertise comes into play by allowing its scientists and chemists to reference performance and compatibility testing between its materials and the hydrogen environment found in these smaller systems.
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 electrolysers and other alternate power systems.
