Water cluster characteristics of fuel cell gas diffusion layers with artificial microporous layer crack dilation
Water cluster characteristics of fuel cell gas diffusion layers with artificial microporous layer crack dilation
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DOI：
10.1016/j.jpowsour.2022.232383
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发表时间：
2023-01
影响因子：
9.2
通讯作者：
D. Niblett;Vahid J. Niasar;S. Holmes;A. Mularczyk;J. Eller;R. Prosser;M. Mamlouk
中科院分区：
文献类型：
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作者：
D. Niblett;Vahid J. Niasar;S. Holmes;A. Mularczyk;J. Eller;R. Prosser;M. Mamlouk
聚合物电解质燃料电池气体扩散层（GDL）中离散水簇的形成可导致催化剂层中氧气传输的阻力增加。本研究探讨MPL裂纹扩展的影响，在X射线计算机断层扫描（CT）的微结构，使用的体积的流体方法（VoF）的水簇的发展。通过体素匹配将VoF计算与手术CT数据进行比较，获得最高88%的准确度。采用三维接触角提取技术，研究了GDL中局部尺度的非均匀润湿性。在模拟研究中，MPL裂纹被创建为水的边界源，并且研究了增加由裂纹覆盖的面积分数对GDL中的水分布的影响。由于面内聚结，增加的开裂在GDL中产生了具有更大连通性的更大离散水簇。面内运动导致团簇合并，在稍后接近突破通道时形成更少、更大的团簇。这一现象表现为水团簇密度（n mm-2）从10降低到5。该不流动的水影响催化剂层处的氧分布（10%局部差异），并因此影响电流密度分布。
The formation of discrete water clusters in polymer electrolyte fuel cell gas diffusion layers (GDL) can lead to increased resistance for oxygen transport in the catalyst layer. This study investigates the effect of MPL crack propagation on the water cluster development in a X-ray computed tomography (CT) microstructure using the volume-of-fluid method (VoF). The VoF calculation was compared to operando CT data by voxel matching, obtaining a maximum 88 % accuracy. Using 3D contact angle extraction, the local scale heterogeneous wettability in the GDL was investigated. In a simulation study, MPL cracks were created as the boundary sources for water and the effect of increasing the area fraction covered by cracks on the water distribution in the GDL was investigated. The increased cracking, created larger discrete water clusters in the GDL with greater connectivity, due to in-plane coalescence. The in-plane movement leads to coalescence of clusters, forming fewer, larger clusters at later times close to breakthrough to the channel. This phenomena is shown by the decrease in water cluster density (n mm−2) from 10 to 5. This immobile water impacts the distribution of oxygen at the catalyst layer (10 % local difference) and therefore the current density distribution.