Wevo, Laufenberg develop continuous process for ‘flat’ elastomer hydrogen gaskets

Stuttgart – Materials specialist Wevo and coatings expert Laufenberg have jointly developed a new “continuous, high-throughput, roll-to-roll production” process for flat elastomer gaskets used in fuel cells and electrolysers.

The method involves applying Wevo’s two-component elastomers in liquid form to a carrier film using Laufenberg’s coating systems, said Wevo in a statement.

The coated film passes through a “multi-zone tunnel oven” where each zone can be set to specific temperatures.

Optional “pre-curing with infrared emitters” shortens curing times and removes air bubbles.

According to Wevo, line speeds of between “0.5 and 50 m/min” enable scalable production.

Depending on design, the process can produce pure elastomer gaskets with layer thicknesses of “20 µm to 2 mm” or hybrid seals with a carrier film, ranging from “70 µm up to 4 mm.”

The output is supplied either as rolls or precision-cut gaskets.

Traditionally, flat gaskets and O-rings for hydrogen applications are produced through injection moulding or other moulding techniques.

Such methods, according to Wevo, are “time- and cost-intensive” and require individual tools and batch production.

The new approach, meanwhile, is claimed to allow “efficient, automated production” without separate moulds.

The choice of elastomer and carrier film can depend on the type of electrolyser, fuel cell or redox flow battery, Wevo explained.

Laufenberg contributes expertise in silicone coating and carrier films, which may either be removed after curing for pure elastomer seals or retained to form hybrid seals, adding stability and pressure resistance.

Wevo supplies specially developed silicones and modified polyurethanes with “low hydrogen permeation,” which it said are already in use as adhesives and liquid sealants.

The materials are now formulated for continuous gasket production, with properties such as pot life and curing time tailored to specific applications.

The partners said the roll-to-roll process offers manufacturers of fuel cells, electrolysers and redox flow batteries “a scalable way” to produce seals while reducing unit costs.