A finite element modeling of PEMFC stack assembly under a novel hydraulic clamping mechanism

Abstract

The clamping force is critical in proton exchange membrane fuel cell (PEMFC) stacking and has crucial effects on PEMFC performance. Clamping mechanisms have a vital impact on the overall performance and uniformity of the equivalent stress distributions. To improve the fuel cell's performance, reduce the risk of gas leakage, and significantly reduce production and operating costs, the assembly process of the PEMFC stack must be numerically simulated beforehand. A three-dimensional finite element model with an active area of 100 cm² was developed with single-cell to multiple cells under conventional and novel hydraulic clamping mechanisms. The mechanical behavior of the PEMFC was numerically investigated. ANSYS mechanical finite element (FE) software was used to observe the stresses and deformations in the PEMFC components during the assembly process. This study numerically analyzed the influences of various compression forces on stress and deformation distributions generated in PEMFC stack components. The FE simulation results show better uniform distributions of equivalent stresses on the membrane for the novel clamping mechanism than the conventional one, and the maximum value of the equivalent stress is 12.914% less than the traditional mechanism. In addition, the maximum equivalent stress values in the membrane of the PEMFC, assembled with the novel clamping mechanism, were calculated as 19.631 MPa for the one-cell configuration, 18.542 MPa for the three-cell configuration, and 18.375 MPa for the five-cell configuration.