In Honor of Nobel Laureate Prof. M Stanley Whittingham
| OPTIMIZING PERFORMANCE AND LIFESPAN OF HIGH-TEMPERATURE PEM FUEL CELLS WITH PBI TECHNOLOGY Kobra Azizi1; Nedjeljko Seselj2; Eftychia Bompolaki3; Silvia M.alfaro4; Lars N. Cleemann3; 1BLUE WORLD TECHNOLOGIES, 3490 Kvistgård, Denmark; 2BLUE WORLD TECHNOLOGIES 3490 KVISTGåRD - DENMARK, Kvistgård, Denmark; 3BLUE WORLD TECHNOLOGIES, Kvistgaard, Denmark; 4BLUE WORLD TECHNOLOGIES, Kvistgård, Denmark; PAPER: 55/Nanomaterials/Regular (Oral) OS SCHEDULED: 16:20/Tue. 28 Nov. 2023/Dreams 3 ABSTRACT: Proton Electrolyte Membrane Fuel Cells (PEMFCs) hold great potential as energy conversion solutions for stationary and transportation purposes. However, in order to compete with internal combustion engines, it is crucial to enhance their durability (1). This study delves into the advancements in membrane electrode assemblies (MEAs) for High-Temperature Polymer Electrolyte Membrane Fuel Cells (HT-PEMFCs). The HT-PEMFCs under investigation were operated within the temperature range of 160-170 °C, utilizing either pure humidified hydrogen or humidified reformate with varying compositions (2). The elevated operating temperature of high-temperature PEM fuel cells (HT-PEMFCs) opens up new horizons, enabling the utilization of methanol or methanol-water mixtures as viable fuels for commercial fuel cell systems. Remarkably, HT-PEM cells exhibit outstanding tolerance to CO impurities, surpassing 3 vol-% without experiencing substantial performance degradation. Additionally, their heightened resistance to H2S and SO2 poisoning significantly bolsters their operational efficiency, paving the way for improved energy conversion. Our research has unveiled the remarkable durability of HT-PEMFCs incorporating a thermally cross-linked m-PBI membrane. Over an extended period of 9,200 hours, these cells exhibited an impressively low decay rate of only 0.5 μV/h at 0.2 A/cm². The single cell performance has shown an exceptional stability over a span of 10,000 hours, with 9.3 μV/h degradation rate at a current density of 0.4 A/cm². These findings signify a significant stride towards attaining long-lasting and reliable HT-PEMFC systems. Additionally, we have demonstrated that increasing the pressure of the incoming gases to 1.5 bar (abs) - as anticipated - leads to performance improvements. Preliminary results have showcased a power density of 0.5 W/cm² at 0.8 A/cm², highlighting the promising potential of this technology. Our study involved rigorous continuous operation and over 1400 start-stop cycles to comprehensively analyze the degradation effects in HT-PEMFCs. The start-stop cycles revealed a degradation rate of 60 µV per cycle, as observed during current density cycling ranging from 0 to 400 mA/cm². These findings shed light on the impact of repeated start-stop events on the performance and longevity of HT-PEMFCs, providing valuable insights for further optimization and durability enhancement. We continue improving our products (HT-PEMFCs), looking for innovative solutions to current limitations on HT-PEMFC durability. References: 1) J. O. Jensen, D. Aili, H. A. Hjuler, Q. Li, High Temperature Polymer Electrolyte Membrane Fuel Cells - Approaches, Status and Perspective, ISBN 978-3-319-17081-7; DOI 10.1007/978-3-319-17082-4, Springer International Publishing, New York, 2015. 2) M. Tonny, D. Jakobsen, L. N. Cleemann, H. Becker, D. Aili, T. Steenberg, H. A. Hjuler, L. Seerup, Q. Li, J.O. Jensen, J. Power Sources, 342 (2017) 570-578. |
