Seeberger Dominik, Hauenstein Pascal, Hartert Adrian, Thiele Simon
Forschungszentrum Jülich GmbH, Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy (IEK-11) Egerlandstr. 3 91058 Erlangen Germany
Department of Chemical and Biological Engineering, Friedrich-Alexander University Erlangen-Nürnberg Egerlandstr. 3 91058 Erlangen Germany.
RSC Adv. 2021 Sep 23;11(50):31477-31486. doi: 10.1039/d1ra05010a. eCollection 2021 Sep 21.
Water management is a very important issue in low temperature fuel cells such as proton exchange membrane fuel cells (PEMFCs) or anion exchange membrane fuel cells. Within bipolar interface fuel cells, water management inhibits an even more critical role. The earlier work on bipolar interface fuel cells (BPIFCs), employing Fe-N/C on the cathode side for the oxygen reduction reaction (ORR) in an alkaline environment, demonstrated increased stability of the catalyst compared to the acidic environment of the conventional PEMFCs. However, for the BPIFCs, severe mass transport limitations (MTL) dramatically reduced the power output of the cell within a few hours. In the present work water transport processes are identified as the source of the observed MTL, after evaluating the performance data of BPIFCs, where the amount of directly deposited anion exchange membrane (AEM) material was varied. It can be seen that the BPIFCs with lower AEM content show an earlier onset of MTL than the cells prepared with higher AEM content. It is shown that the AEM can be used as a tool to regulate the influx rate of product water from the bipolar interface into the CCL and that flooding of the porous layers is identified as the main source of the observed MTL. This work paves the way for further development of BPIFCs using Fe-N/C at the cathode electrode, as novel cell design strategies can now focus exclusively on avoiding flooding phenomena.
水管理在低温燃料电池中是一个非常重要的问题，例如质子交换膜燃料电池（PEMFC）或阴离子交换膜燃料电池。在双极界面燃料电池中，水管理起着更为关键的作用。早期关于双极界面燃料电池（BPIFC）的研究，在阴极侧采用Fe-N/C在碱性环境中进行氧还原反应（ORR），结果表明与传统PEMFC的酸性环境相比，催化剂的稳定性有所提高。然而，对于BPIFC，严重的传质限制（MTL）在几小时内显著降低了电池的功率输出。在本工作中，在评估了直接沉积的阴离子交换膜（AEM）材料量不同的BPIFC的性能数据后，确定水传输过程是观察到的MTL的来源。可以看出，AEM含量较低的BPIFC比AEM含量较高的电池更早出现MTL。结果表明，AEM可作为一种工具来调节产物水从双极界面流入催化层的速率，并且多孔层的水淹被确定为观察到的MTL的主要来源。这项工作为进一步开发在阴极电极使用Fe-N/C的BPIFC铺平了道路，因为新的电池设计策略现在可以专门专注于避免水淹现象。
