INT2 - AddFlow

How can the design of fuel cells be optimized using additive manufacturing? For the efficient operation of fuel cells, the supply of the reactant gases and the discharge of the reaction product water are of particular importance. In the interdisciplinary approach pursued here, the possibilities of additive-subtractive manufacturing are combined with surface functionalization to create hydrophilic or hydrophobic surfaces. In this way, the challenges of optimal gas distribution and the production of flow-adapted, very flat, thin components are to be overcome.

Aim, approach and benefit

The aim of the project is to increase the efficiency of polymer electrolyte membrane (PEM) fuel cells by selectively creating transport structures in the gas diffusion layer (GDL) as well as the bipolar plate (BPP).

A combined additive and subtractive laser process is to be used to generate flow-optimized channel structures that ensure homogeneous incident flow to the PEM. At the same time, the component surface is to be structured with the laser to specifically create water-repellent and water-conducting areas. This will be used to specifically influence the supply of the reactants (hydrogen and oxygen) and the discharge of the reaction product (water).

A particular challenge is posed by the ratio of component thickness to surface area in combination with the processes used. Process strategies have to be developed to minimize the distortion of the component. At the same time, however, the component should have highly filigree channels with a structured surface.

The design, fabrication and testing of the structures is carried out across universities by a combination of simulation and experimental investigation.

Schematic representation of the flow structure with discharge channels for gases (gray arrows) and for water (blue).