Electro-thermal mapping of polymer electrolyte membrane fuel cells with a fractal flow-field
Electro-thermal mapping of polymer electrolyte membrane fuel cells with a fractal flow-field
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DOI：
10.1016/j.enconman.2021.114924
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发表时间：
2021-12
影响因子：
10.4
通讯作者：
V. S. Bethapudi;J. Hack;G. Hinds;P. Shearing;D. Brett;M. Coppens
中科院分区：
文献类型：
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作者：
V. S. Bethapudi;J. Hack;G. Hinds;P. Shearing;D. Brett;M. Coppens
聚合物电解质膜燃料电池（PEMFC）的电热图显示了电流密度和温度的空间分布，这是有用的，以评估其性能。在这里，电热映射进行了第一次对PEMFC与分形阴极流场，其设计模仿肺内的高效，可扩展的空气输送。这样的地图进行比较与传统的单蛇形流场PEMFC。通过分析不同反应物相对湿度（RH）和电池电压下电流密度和温度的表面分布来表征每个电池的性能。段电流密度和表面温度之间的关系，以及反应物的相对湿度和电池的工作条件。具有分形流场的电池提供更好的电化学性能，并表现出更均匀的电流分布相比，那些与单蛇形流场，其中的电流分布是不均匀的，由于电池淹没。分形流场的电池表面温度高于单蛇形流场的电池，这与所观察到的电池性能一致。此外，电化学阻抗谱表征表明单蛇形细胞中的洪水，但不是在分形细胞。
Electro-thermal maps of a polymer electrolyte membrane fuel cell (PEMFC) show the spatial distribution of current density and temperature, which is useful to evaluate their performance. Here, electro-thermal mapping is carried out for the first time on a PEMFC with a fractal cathode flow-field, the design of which emulates the efficient, scalable air transport inside the lungs. Such maps are compared with those of a conventional single-serpentine flow-field PEMFC. Each cell’s performance is characterised by analysing the surface distribution of current density and temperature at different reactant relative humidity (RH) and cell voltage. Relationships are shown between segment current densities and surface temperatures, and between reactant relative humidity and cell operating conditions. The cells with a fractal flow-field deliver better electrochemical performance and exhibit more homogeneous current distributions compared to those with a single-serpentine flow-field, in which the current distribution is non-uniform due to cell flooding. The surface temperatures are higher in cells with a fractal flow-field than in those with a single-serpentine flow-field, consistent with the observed cell performances. In addition, electrochemical impedance spectroscopy characterisation indicates flooding in the single-serpentine cells, but not in the fractal cells.