(Aachen) – The Fraunhofer Institute for Production Technology IPT in Aachen is developing a pilot line in which fuel cell components can both be manufactured and assembled into the finished product. The “stacks”, i.e. the stacks on which the reactions from hydrogen to water and electricity generation take place, consist of several hundred bipolar plates stacked closely together. The researchers explain that these are traversed by a delicate system of channels through which the hydrogen is supplied on one side and the water produced during the chemical reaction in the stack is removed on the other side.
The plates are only about 100 micrometers thick and are “more like foil.” A finished bipolar plate consists of a left and a right half, between which the fine canal system lies. Both halves would have to be welded together very precisely. There are also various cleaning steps.
Fuel cell production in Europe is too slow
Fuel cell production has so far been complex and too slow, according to a statement from the IPT. The European “Hydrogen Strategy” envisages that hydrogen will be used in industry and road transport to replace petrol and diesel. But mass production of the many millions of fuel cells required does not yet exist in Europe. What is currently missing is a closed process chain in which fuel cell components are manufactured and assembled on an assembly line, so to speak.
The Fraunhofer IPT team says it has now developed a production line in which “all components and the bipolar plates are passed on using gripping tools (pick-and-place machines) in such a way that a flowing process results.”
Production required every second
“We need consistent production lines that can eject and process components every second,” says Christoph Baum, Managing Director of Fraunhofer IPT. “The industry in Europe is currently still a long way from that.”
Rather, components are now manufactured by different producers and then assembled to form the fuel cell. Manufacturing steps such as forming, cleaning, coating or joining the fuel cell components also took place “spatially separate from each other in different machine islands”. “All in all, this results in complex logistics within production,” says Christoph Baum. Parts would have to be picked up, put down and stored several times – “that’s time-consuming”.
Production from the roll
The automation of the pilot line is being further developed by IPT in the CoBIP project (continuous roll-to-roll production of bipolar plates for fuel cells) together with the Fraunhofer Institute for Laser Technology ILT, the Research Center Jülich and several industrial partners. The goal is a system in which the bipolar plates are processed in a film strand from the roll. The film then goes through the machine “and with it all process steps from the blank to forming, vapor deposition and cleaning to joining with the laser.” Only at the very end are the bipolar plates cut off from the strand. “This consistent production from the roll to the finished piece will save many handling steps,” say the scientists.
The system is designed so flexibly that industrial partners can exchange and test individual production modules as they wish. A high cycle rate could be achieved by allowing several devices to work in parallel or connecting them in series, for example lasers for joining the plate halves.
“In Europe we have a lot of system know-how to produce high-quality fuel cells. “But there is a lack of opportunities to produce fuel cells on an industrial scale at competitive prices,” says Christoph Baum. The hurdle of industrial production scaling should not be underestimated. “Similar to batteries, transferring systems from the laboratory to mass production is a complex step.”
The new pilot line will be from April 12th to 16th, 2021 during the Hannover Messe Digital Edition presented. In a live stream, the Fraunhofer IPT, together with the Fraunhofer Institute for Materials and Beam Technology IWS and the Fraunhofer Institute for Machine Tools and Forming Technology IWU, reports on initial research results.
Photos
In the continuous production facility at Fraunhofer IPT, fuel cell components will in future be able to be processed every second. © Fraunhofer IPT
