The development of hardware and automated production is correspondingly dynamic. Schmalz adapts its handling systems to the constantly changing requirements - new process steps, surfaces and materials.

From 2001 onwards, things became restless among combustion engines. At the IAAs at the beginning of the 21st century, more and more car manufacturers drew attention to their "blue" vision of the mobility of the future: vehicles powered by fuel cells. German car manufacturers also sent test fleets onto the roads - quiet, clean and, subject to a few safety measures, just as easy to use as petrol or diesel. Then the fuel cell withdrew from public attention.

After years of promoting electromobility with batteries as energy storage systems, hydrogen users are once again taking center stage. In a study published in April 2021, the VDE defined the "drive portfolio of the future" as a demand-oriented mix: battery for cars, battery or fuel cell for trucks and e-fuels for existing vehicles, motorsport and classic cars. The fact is: the fuel cell is establishing itself and is an opportunity for emission-free driving and the economy in Germany.

Efficient production

Efficient production also requires automated gripping systems that handle the various components and assemblies gently and safely. "The fuel cell is currently a highly dynamic topic. In Germany and Europe, as well as in individual Asian countries, funding programs are allowing new players to emerge and the big names to establish themselves further," says Matthias Müller, Head of International Sales and International Industry and Key Account Management at J. Schmalz. The challenge for him and his team is to be involved in all projects and to be able to serve the high level of innovation.

"We manage this without any problems thanks to our industry management. This is our linchpin, which identifies relevant contacts and provides customers with professional support. Behind our success is the close cooperation with our sales organizations. With innovative solutions and a strong development department, we can keep pace with the dynamics of the market," explains Müller. The Black Forest company has a correspondingly strong network: Schmalz has been working with car manufacturers for decades and is involved in national research projects. The aim is the economical series production of fuel cells. "Automation is crucial here, and that's where we come in," adds Müller.

With its comprehensive gripper portfolio, Schmalz is well positioned for this role. And yet there is still a lot to do in the development department in Glatten. "The dynamic nature of the industry is reflected in the demands placed on our designers and developers: they have to constantly adapt the gripper systems to changing production steps, workpieces and materials as well as new surface structures."

Reaching into the heart of the fuel cell

To understand what Matthias Müller means, it helps to look inside a fuel cell, the structure of which is basically similar to a battery: an electrolyte layer separates the anode and cathode and ensures the transport of ions. This membrane electrode assembly (MEA) is the heart of every fuel cell. A gas diffusion layer follows on the outside, to which bipolar plates are attached.

The systems used in the production of the MEAs must be particularly gentle on the sensitive surfaces and ideally handle all components. Schmalz therefore combines several vacuum circuits and gripping technologies to pick up the catalyst-coated membrane, gas diffusion layer and sealing frame sequentially. A high volume flow and the wear- and energy-efficient, pneumatic vacuum generation by the SCPM compact ejectors prevent particle residues on the workpieces. "This means that our system can also be used in clean rooms," says Müller. The full-surface gripping principle of the surface gripper, which combines large-surface contact with a low vacuum level and a high volume flow, protects the thin films from deformation. As in battery production, the vacuum expert must permanently ensure safe electrostatic discharge - with the help of ESD-compliant contact surfaces.

From the BPP to the stack

Bipolar plates (BPP) made of metal or graphite materials frame the MEAs. Their task is to conduct the hydrogen to the anode and the oxygen to the cathode as well as to remove the reaction water and release the thermal and electrical energy. The design of their surfaces influences the efficiency of the subsequent fuel cell. Research and development are correspondingly dynamic. "Our development has to keep up with this pace and adapt our grippers to the changing formats and structures," explains Müller.

In principle, Schmalz uses surface grippers for the safe handling of structured flow fields. Additional integrated suction pads increase the permissible lateral force - so the BPP remains in place despite high acceleration. The plastic of the suction plates and the HT1 material of the suction pads protect the coated surfaces from damage and chemical residues. The SBS floating suction pad reliably sucks in convex or concave BPP halves and pulls them flat with its high holding forces. Integrated sensors also clearly identify the components. These are also important in stack production, i.e. the joining of MEAs, gas diffusion layers and bipolar plates.

Depending on the various components, the entire range of special grippers from Schmalz can be found in this production step: FLGR surface grippers, SCG flow grippers, SBS suction pads and conventional vacuum suction pads. Their different technologies - full-surface or low-contact gripping - keep the surface pressure low and the surfaces free from contamination. At the same time, they keep pace with the dynamics of the production process.

"The requirements for fuel cell production are similar to battery production - we are handling comparable materials here. They are thin, coated and therefore extremely sensitive. And we keep pace with the pace of development - both in research projects and in series production," summarizes Müller.