The fuel cell is a serious solution for zero-emission mobility. While it had long disappeared from the scene, it is now establishing itself as a viable option for zero-emission strategies. The development of hardware and automated production is correspondingly dynamic. This is where Schmalz steps in and adapts its handling systems to the constantly changing requirements – new process steps, surfaces and materials.
From 2001 onward, things got restless among the combustion engines. At the IAAs at the beginning of the 21st century, more and more automakers drew attention to their «blue» vision of the mobility of the future: vehicles powered by fuel cells. German automakers also sent test fleets onto the roads – quiet, clean and, subject to a few safety measures, just as easy to operate as gasoline or diesel engines. Then the fuel cell withdrew from public attention. After years of promoting electromobility with batteries as energy storage, hydrogen users are now once again stepping into the spotlight. In a study published in April 2021, the VDE defines the «drive portfolio of the future» as a demand-oriented mix: battery for passenger cars, battery or fuel cell for trucks and e-fuels for existing vehicles, motor sports and classic cars. For this purpose, the German Association for Electrical, Electronic & Information Technologies (VDEI) surveyed politicians and business leaders. The fact is: The fuel cell is establishing itself and is an opportunity for emission-free driving and the economy in Germany. 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. Especially in Germany and Europe, as well as in individual countries in Asia, subsidy 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 GmbH. The challenge for him and his team is to be on top of all projects and to be able to serve the high level of innovation. «We manage this without any problems – thanks to our industry management. That’s our linchpin, uncovering relevant contacts and providing customers with professional support. Behind the success is the very close cooperation with our sales organizations. With highly innovative solutions and strong development departments, we can keep up with the dynamics in the market,» explains Müller. The Black Forest company has a correspondingly strong network: Schmalz has been working with automotive manufacturers for decades and is involved in national research projects. The goal: the economical series production of fuel cells. «Automation is crucial here, and that’s where we come in,» adds Müller. Schmalz is well positioned for this role with its comprehensive gripper portfolio. And yet, there is still work to be done in the development department in Glatten. «The dynamics of the industry are reflected in the demands placed on our designers and developers: They have to permanently adapt the gripping systems to changing production steps, workpieces and materials, and 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, whose structure is basically reminiscent of a battery: an electrolyte layer separates the anode and cathode and ensures ion transport. This membrane electrode assembly (MEA) is the heart of every fuel cell. On the outside, there is a gas diffusion layer, to which bipolar plates are attached.
The systems that access the MEAs during production must be particularly gentle on the sensitive surfaces and ideally handle all components. Therefore, Schmalz combines several vacuum circuits and gripping technologies to sequentially pick up the catalyst-coated membrane, gas diffusion layer as well as sealing frame. 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 our system can also be used in clean rooms,» explains Müller. The full-area gripping principle of the large-area gripper, which combines large-area contact with a low vacuum level and a high volume flow, protects against deformation of the thin films. 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: to conduct the hydrogen to the anode and the oxygen to the cathode, as well as to remove the reaction water and deliver 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 must keep up with this pace and adapt our grippers to the changing formats and structures,» Müller clarifies.
In principle, Schmalz uses area grippers for safe handling of the structured flow fields. Additionally 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 as well as chemical residues. The SBS floating suction pad reliably sucks convex or concave BPP halves and pulls them level with its high holding forces. Integrated sensors also clearly identify the components. These are also important in stack production, i.e. the merging of MEAs, gas diffusion layers and bipolar plates.
According to the different components, the entire range of special grippers from Schmalz can be found in this production step: FLGR area grippers, SCG flow grippers, SBS floating suction pads and conventional vacuum suction pads. Their different technologies – whether full-surface or low-contact gripping – keep surface pressure low and surfaces free of contamination. At the same time, they keep pace with the dynamics in the production process.
«The demands in fuel cell production are similar to battery production – after all, we handle comparable materials here. They are thin, coated and therefore extremely sensitive. And we keep pace with the development dynamics – both in research projects and in series production,» Matthias Müller sums up. After talking to the head of international industry management, one thing is clear: Whether it’s the carmakers’ «blue» vision or the politicians’ «green» plan – the lard blue will always shine through in the automated production of fuel cells.