Wang Hao, Yang Xiaoxing, Yang Guogang, Zhang Guoling, Li Zheng, Li Lingquan, Huang Naibao
Marine Engineering College, Dalian Maritime University, Dalian 116026, China.
School of Marine Engineering, Guangzhou Maritime University, Guangzhou 510725, China.
Nanomaterials (Basel). 2024 Dec 14;14(24):2012. doi: 10.3390/nano14242012.
Proton exchange membrane fuel cells (PEMFCs) are being pursued for applications in the maritime industry to meet stringent ship emissions regulations. Further basic research is needed to improve the performance of PEMFCs in marine environments. Assembly stress compresses the gas diffusion layer (GDL) beneath the ribs, significantly altering its pore structure and internal transport properties. Accurate evaluation of the PEMFC cathode's electrochemical performance at the pore scale is critical. This study employs a three-dimensional multicomponent gas transport and electrochemical reaction lattice Boltzmann model to explore the complex interplay between GDL compression and factors such as overpotential, pressure differential, porosity, and porosity gradient on PEMFC performance. The findings indicate that compression accentuates the reduction in oxygen concentration along the flow path and diminishes the minimum current density. Furthermore, compression exacerbates the reduction in current density under varying pressure conditions. Increased local porosity near the catalyst layer (CL) enhances oxygen accessibility and water vapor exclusion, thereby elevating the mean current density. Sensitivity analysis reveals a hierarchy of impact on mean current density, ranked from most to least significant: overpotential, porosity, compression, porosity gradient, and pressure difference. These insights into the multicomponent gas transfer dynamics within compressed GDLs inform strategic structural design enhancements for optimized performance.
质子交换膜燃料电池（PEMFCs）正被用于海事行业的应用中，以满足严格的船舶排放法规。需要进一步开展基础研究，以提高PEMFCs在海洋环境中的性能。组装应力会压缩肋条下方的气体扩散层（GDL），显著改变其孔隙结构和内部传输特性。在孔隙尺度上准确评估PEMFC阴极的电化学性能至关重要。本研究采用三维多组分气体传输和电化学反应格子玻尔兹曼模型，探讨GDL压缩与过电位、压差、孔隙率和孔隙率梯度等因素对PEMFC性能的复杂相互作用。研究结果表明，压缩会加剧沿流动路径的氧气浓度降低，并降低最小电流密度。此外，在不同压力条件下，压缩会加剧电流密度的降低。催化剂层（CL）附近局部孔隙率的增加提高了氧气可及性和水蒸气排除能力，从而提高了平均电流密度。敏感性分析揭示了对平均电流密度影响的层次结构，从最显著到最不显著依次为：过电位、孔隙率、压缩、孔隙率梯度和压差。这些关于压缩GDL内多组分气体传输动力学的见解为优化性能的战略结构设计改进提供了依据。
