A team from Fraunhofer IPT is developing a continuous production line that will be able to process fuel cell components in cycles lasting just seconds. The pilot line is set to be presented at the Hannover Messe Digital Edition from 12-16 April 2021.

In a live stream, Fraunhofer IPT, together with the Fraunhofer Institute for Material and Beam Technology IWS and the Fraunhofer Institute for Machine Tools and Forming Technology IWU, will present the Fraunhofer-Gesellschaft’s action plan and initial research results for the cost-effective, automated mass production of fuel cells.

The aim of the three institutes, which specialize in the field of manufacturing, is to accelerate the economic breakthrough of fuel cells and electrolyzers both nationally and internationally. Moreover, they plan to transfer the action plan and the individual technologies for the production of fuel cells from research to industrial application.

The non-stop production plant at Fraunhofer IPT is set to process fuel cell components in cycles lasting just seconds. © Fraunhofer IPT

Germany and Europe are on their way to a hydrogen future. The German federal government approved its hydrogen strategy in June of last year. The strategy aims to build electrolysis plants for hydrogen production with a total output of 10 GW in Germany by the year 2040.

For Europe, the European Commission is proposing in its “Hydrogen Strategy” to expand electrolysis output by a further 40 GW. Hydrogen is set to be used in industry and in the future also in road traffic, finally heralding a shift away from gasoline and diesel fuel.

The many millions of vehicles will need many millions of fuel cells to convert hydrogen into power, but as yet, Europe has no mass production facility that could cover this demand. What is most lacking is a closed production chain for making fuel cell components and then assembling them to form the finished item.

We need non-stop production lines that are able to drop and process components in cycles lasting just seconds. Industry in Europe is still quite a long way from that point.

—Dr. Christoph Baum, Managing Director of the Fraunhofer Institute for Production Technology IPT in Aachen

Right now, various components are manufactured by various producers and then assembled to create the fuel cell. And the production steps such as forming, cleaning, coating or joining the fuel cell components are spatially separated from one another in various machine islands.

All in all, the logistics within our production facilities are complex. Parts have to be picked up, placed and buffered multiple times—that’s a time-consuming business.

—Christoph Baum

Therefore, Fraunhofer IPT is developing for the first time in a research environment a non-stop pilot line in which fuel cell components are made and assembled into the finished product in one place.

Specifically, this is about producing the fuel cell stack on which hydrogen is converted to water and the energy is collected. This stack consists of hundreds of bipolar plates arranged on top of one another. The bipolar plates are pulled through an intricate system of millimeter thick channels, the hydrogen being fed in at one end and the water produced by the chemical reaction in the stack being fed out at the other.

Producing these bipolar plates is a challenge in itself. The plates are only about a hundred micrometers thick and tend to resemble a film rather than a plate. They have to be moved very carefully to make sure nothing gets creased or wrinkled.

First, presses are used to emboss the channel structures onto the plate blanks. They are then coated under vacuum to reduce their electrical resistance and make them more corrosion-proof. A finished bipolar plate consists of a left half and a right half, with the fine channel system between. The two halves therefore need to be welded together with a high degree of precision. There are also various cleaning steps.

The team at Fraunhofer IPT has now developed a production line on which special pick-and-place handling devices hand down all components and the bipolar plates in such a way as to create a fluent process.

Because some process steps are faster than others, the challenge is to optimize the flow as a whole so that neither jams nor waiting times occur. The blank pressing process, referred to as deep drawing, is done in just about one second, while the deposition of the protective layer takes much longer.

We are predicting that hundreds of thousands of bipolar plates will be needed for the hydrogen economy of the future. For this reason, we are striving to achieve a throughput of at least one bipolar plate per second across all plants.

—Christopher Baum

In the CoBIP project (continuous roll-to-roll production of bipolar plates for fuel cells), Fraunhofer IPT is currently driving the automation of the pilot line together with the Fraunhofer Institute for Laser Technology ILT, the Jülich Research Center and several industrial partners.

The strip passes through the machine and hence through all process steps—from the blank to the forming, the deposition of the protective coating to the cleaning through the joining process by the laser. Only at the very end are the bipolar plates cut off the strip and isolated. This continuous process from the roll to the finished item will save a number of handling steps.

The plant is designed to be so flexible that industrial partners are able to exchange and test individual production modules at will. A high cycle rate allows several devices to operate in parallel or to be connected in series, lasers for joining the plate halves, for example.

It’s true that in Europe we have a good deal of system expertise for manufacturing high-grade fuel cells. But we lack the facilities to produce fuel cells on an industrial scale at competitive prices—production lines like we are already seeing at Hyundai or Toyota.

—Christoph Baum