Xu Linlin, Trogadas Panagiotis, Zhou Shangwei, Jiang Shuxian, Wu Yunsong, Rasha Lara, Kockelmann Winfried, Yang Jia Di, Neville Toby, Jervis Rhodri, Brett Dan J L, Coppens Marc-Olivier
Centre for Nature-Inspired Engineering, Department of Chemical Engineering, University College London, London, WC1E 7JE, UK.
Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki, 54124, Greece.
Adv Sci (Weinh). 2024 Sep;11(36):e2404350. doi: 10.1002/advs.202404350. Epub 2024 Jul 25.
Effective water management is crucial for the optimal operation of low-temperature polymer electrolyte membrane fuel cells (PEMFCs). Excessive liquid water production can cause flooding in the gas diffusion electrodes and flow channels, limiting mass transfer and reducing PEMFC performance. To tackle this issue, a nature-inspired chemical engineering (NICE) approach has been adopted that takes cues from the integument structure of desert-dwelling lizards for passive water transport. By incorporating engraved, capillary microchannels into conventional flow fields, PEMFC performance improves significantly, including a 15% increase in maximum power density for a 25 cm cell and 13% for a 100 cm cell. Electro-thermal maps of the lizard-inspired flow field demonstrate a more uniform spatial distribution of current density and temperature than the conventional design. Neutron radiography provides evidence that capillary microchannels in the lizard-inspired flow field facilitate the efficient transport and removal of generated liquid water, thereby preventing blockages in the reactant channels. These findings present a universally applicable and highly efficient water management strategy for PEMFCs, with the potential for widespread practical implementation for other electrochemical devices.
有效的水管理对于低温聚合物电解质膜燃料电池（PEMFC）的最佳运行至关重要。过多的液态水生成会导致气体扩散电极和流道发生水淹，限制传质并降低PEMFC性能。为解决这一问题，采用了一种受自然启发的化学工程（NICE）方法，该方法从生活在沙漠中的蜥蜴的外皮结构中获取线索以实现被动水传输。通过将刻有图案的毛细管微通道纳入传统流场，PEMFC性能显著提高，对于一个25厘米的电池，最大功率密度提高了15%，对于一个100厘米的电池，提高了13%。受蜥蜴启发的流场的电热图表明，与传统设计相比，电流密度和温度的空间分布更加均匀。中子射线照相术提供的证据表明，受蜥蜴启发的流场中的毛细管微通道有助于高效传输和去除生成的液态水，从而防止反应物通道堵塞。这些发现为PEMFC提出了一种普遍适用且高效的水管理策略，具有在其他电化学装置中广泛实际应用的潜力。
