Performance investigation on the new bionic leaf vein flow field for a proton exchange membrane fuel cell

The configuration of the bipolar plate significantly affects gas distribution and water management within a proton exchange membrane fuel cell (PEMFC), thereby playing a crucial role in its performance. This study designs a series of improved new bionic leaf vein flow fields and examines the performance of PEMFC through numerical simulation and experimental research using a conventional parallel flow field (CPFF) and five new bionic leaf vein flow fields (NBFF-case1 similar to 5). The results indicate that NBFF demonstrates a greater peak power density in comparison to CPFF. Specifically, when T-cell = 353 K, lambda(a) = 1.8 and lambda(c) = 2.0, NBFF-case5 achieves a peak power density that is 31 % higher than CPFF. Moreover, NBFF generally exhibits reduced oxygen transport resistance compared to CPFF, leading to enhanced gas diffusion uniformity and improved gas concentration distribution. Among the NBFF cases with guide vanes (NBFF-case3 similar to 5), NBFF-case5 outperforms NBFF-case3 by 7.2 % in terms of peak power density, emphasizing the importance of guide vane placement for enhancing PEMFC performance. The integration of simulation and experimental data reveals that, compared with CPFF, the NBFF structure shows better current density distribution and liquid water management, which significantly enhances the output power of PEMFCs. Among them, the PEMFC with the NBFF-case5 structure has the highest output performance.