Structural optimization of distribution zone for large-sized PEMFC with high power density

•The flow uniformity of large-sized PEMFC was improved with an optimized distribution zone.•Partially dotted matrix can achieve both improved uniformity and reduced manufacturing cost.•Positional and size effects of partially dotted matrix were clarified. Proton exchange membrane fuel cell (PEMFC) is an important device to convert clean-fuel hydrogen into electricity, which has the potential to reduce pollutant emission and our dependence on fossil fuels. Of the many development and manufacturing challenges that need to overcome before large-scale commercialization can be realized, one of the most pivotal ones is flow distribution uniformity. To this end, a distribution zone with partially dotted matrix was proposed, and showed much more effectiveness when compared with the un-optimized distribution zone with an empty chamber. The positional and size effect of the dotted matrix was investigated, and results showed that flow uniformity was maximized when the dotted matrix was placed near the gas inlet. Interestingly, less dotted matrix size could achieve better performance, indicating the potential of this approach to reduce manufacturing cost. The optimized system could achieve more uniform flow with standard deviation of 1.808 × 10-8, maldistribution factor of 3.967 × 10-3 and variable coefficient of 0.4143%, more superior to other similar models reported. Furthermore, a full cell-level simulation was also conducted, affirming the superiority of the proposed model with increased power densities and water distribution uniformities.