The current limitations of small production volumes and high prices pose significant obstacles to the widespread deployment of fuel cells, demanding the development of new manufacturing technologies to promote and solidify their market adoption. The polymer electrolyte membrane fuel cell (PEMFC) is particularly interesting for transport and mobile applications, where hundreds of single cells are combined into a stack providing the required power levels. In such a system, hundreds of sealings play a crucial role to guarantee reproducible assembly conditions and ensure media tightness for a safe operation.



The present work explores the application of stencil printing as a novel technique for producing fuel cell sealings. The primary objective is to achieve process conditions to reliably print sealings and structures with a layer thickness of at least 500~µm while minimizing the process cycle time to as close as 3 seconds. Prominent print defects emerging during the squeegee and separation process of stencil printing are identified and their corresponding formation mechanisms thoroughly assessed. Here, a key focus lies on understanding how the rheological properties of the print material impact the quality of the print results using quantifiable criteria. Thus, numerous rheological tests using standard laboratory equipment were carried out to characterise the flow and deformation behaviour of print materials. Decisive influencing parameters and relationships were integrated into different indicators and models, enhancing the transferability of the obtained findings to more general stencil printing applications and to the field of applied rheology.