The electrolyzer manufacturer Stargate Hydrogen, Estonia, is now using BASF’s Ultrason^® to manufacture the frames in its stacks used for alkaline water electrolyzers (AWE). The polysulfone (PSU) Ultrason^® S replaces metals such as nickel, resulting in significantly lighter stacks. This substitution is possible because BASF’s high-performance thermoplastic offers high temperature and chemical resistance also in harsh alkaline conditions. It can withstand high stack pressures due to excellent compression strength. As Ultrason can be injection-molded, it provides greater design flexibility for easier functional integration than metal.

The collaboration between Stargate Hydrogen and BASF has yielded an exceptional result: the pressurized stacks of the Stellar series are designed for long operational lifespans, supporting reliable H₂ production, and reducing downtime and maintenance costs. This durability enhances the economic feasibility of green H₂ production, making it a cost-effective solution.

Alkaline electrolyzers are the most robust and proven form of electrolysis for producing H₂ from water. “Stargate Hydrogen manufactures electrolyzer stacks to empower system integrators with the most flexible and scalable technology,” said Marko Virkebau, CEO of Stargate Hydrogen. “We deliver not only a piece of hardware but a partnership from day one until H₂ is being produced reliably. We build upon the best aspects of AWE technology and complement it with breakthrough materials. This is why we chose BASF’s Ultrason for the frames in our Stellar electrolyzer series: it combines light weight with outstanding performance, thus helping us to improve the efficiency and lower the cost of alkaline electrolyzers.”

This results in a new class of electrolyzers with high current densities, offering an innovative approach to decarbonizing sectors such as heavy transport, steel manufacturing and the chemical industry.

Tailored Ultrason portfolio for scaling up H₂ production. The patent-pending design of Stargate Hydrogen’s Stellar stacks incorporates frames with a diameter of 85 cm. BASF’s specialty plastic Ultrason enables these frames to be large, robust, and durable, with a focus on higher operating temperatures and extended lifetimes. It withstands the extreme forces in AWE systems and shows excellent hydrolytic stability. Its stable mechanical properties make it suitable for current (90°C) and future (> 100°C) electrolyzers.

“With Ultrason, our customers can upscale green H₂ production, thus advancing the transformation to clean energy,” said Jochen Schmid from Global Business Development Ultrason at BASF. “Its excellent performance under the harsh conditions of water electrolysis makes it the ideal material for various electrolyzer technologies and applications. We are proud to support Stargate Hydrogen in its scale-up strategy — from selecting the appropriate Ultrason grade to part and tool design and final frame production.”

BASF offers a tailored Ultrason portfolio to meet the specific performance requirements of alkaline water (AWE), proton exchange membrane (PEM), and anion exchange membrane (AEM) electrolyzers. Supported by BASF’s application expertise and local technical support, the material range for electrolyzer components includes polyarylethersulfones (PSU, PESU, PPSU) for frames, gaskets, and separator membranes.

Ultrason is the trade name for BASF’s product range of polyethersulfone (Ultrason^® E), polysulfone (Ultrason^® S) and polyphenylsulfone (Ultrason^® P). The high-performance thermoplastic is used to manufacture water filtration membranes, stylish, durable and safe household and catering applications as well as lightweight components for the automotive and aerospace industries. Ultrason brands can substitute thermosets, metals, glass and ceramics in many applications because of their extraordinary property profile.