PEMFC Seal Design and Optimization by Taking into Account of Gasket Shape Profile and Stack-Up Assembly Tolerance

Stable seals are essential for the safe operation of the PEMFC. However, manufacturing errors of PEMFC components and assembly errors during assembly process often result in great variability in PEMFC sealing performance. This study investigates the relationship between stack-up assembly tolerances and profile tolerances of sealing gasket surface on PEMFC leakage rates during assembly process. A tolerance analysis was first carried out to determine the relationship between stack-up assembly tolerances and section alignment errors, and the relationship between gasket surface profile tolerances and gasket section errors. Finite element and Roth models were then used to investigate the relationship between manufacturing errors and leakage rates. The results show that assembly errors have a significant effect on the leakage rate and there is a linear increasing relationship between height error and leakage rate; on the other hand, an increase in the width error leads to a linear decrease in the leakage rate. The method clearly shows the relationship between the manufacturing tolerances of seals and bipolar plates and the leakage rate of the PEMFC, providing an important theoretical basis for the design of tolerances of seals and bipolar plates.