| Summary: | 碩士 === 國立臺灣大學 === 機械工程學研究所 === 98 === This thesis proposes a systematic method to evaluate the performance of a metallic bipolar plate fuel cell with different parameters. Firstly, a finite element analysis (FEA) is used to obtain the structural responses of the fuel cell stack, such as the contact pressure between gas diffusion layers (GDL) and metallic bipolar plates, and also the strain distribution of the GDL. A parametric model with given design parameters is developed for this analysis. Secondly, the performance of the fuel cell is evaluated from the results of the FEA through a series of derivations. The relationship between the contact pressure and contact resistance is used to calculate the whole electric resistance of the fuel cell. The relationship between the GDL strain and effective diffusion coefficient is studied to evaluate the limiting current density of the fuel cell. Then, the formulations for the polarization and power curves are derived with the calculated electric resistance and the computed limiting current density. Finally, the relationship between the fuel cell performance and the structural design parameters are discussed by the formulations of the polarization and power curves. The optimum design procedure is executed to improve the performance of fuel cell with the appropriate rib shape and clamping pressure. In conclusion, this thesis studies the relationships that can transfer the FEA results to the fuel cell performance and the optimization of the fuel cell performance by modifying the design parameters of the fuel cell structure. The systematic method of the performance evaluation gives a satisfactory result in the structural design.
|
|---|
