The proton exchange membrane fuel cell (PEM-FC) makes it possible to provide electrical energy for a wide range of applications without polluting emissions as a by-product. However, various challenges need to be overcome before widespread use of this technology is possible. In addition to optimizing its performance and lifetime, a key challenge is to reduce production costs. Production processes significantly affect these three objectives. Tighter manufacturing tolerances on the main components, membrane exchange assembly and bipolar plate, for example, can improve the functions above. However, manufacturing to tighter tolerances usually leads to higher production costs. To resolve the contradiction between 'tight tolerances' and 'low costs', the principle of dynamic tolerancing was developed. So far, this principle has only been implemented for a shaft-hub connection. The approach presented here applies the principle to the assembly process of a stack for a PEM-FC and shows how the channel offset within a stack can be reduced without increasing the requirements for individual part tolerances.
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