Degradation of polymer electrolyte membrane fuel cells repetitively exposed to reverse current condition under different temperature

• Published in: Journal of power sources 2011-12, Vol.196 (23), p.9906-9915
• Main Authors: Jo, Yoo Yeon, Cho, EunAe, Kim, Jung Hyeun, Lim, Tae-Hoon, Oh, In-Hwan, Kim, Soo-Kil, Kim, Hyung-Juhn, Jang, Jong Hyun
• Format: Article
• Language: English
• Subjects: Applied sciences; Carbon corrosion; Cycles; Degradation; Direct energy conversion and energy accumulation; Durability; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Electrochemical impedance spectroscopy; Energy; Energy. Thermal use of fuels; Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc; Exact sciences and technology; Fuel cells; Operating temperature; Polymer electrolyte membrane fuel cells; Scanning electron microscopy; Shutdowns; Startup/shutdown cycle; Voltammetry
• ISSN: 0378-7753; 1873-2755
• DOI: 10.1016/j.jpowsour.2011.08.035

► Performance decay and degradation rate was systematically studied at operating temperatures of 40, 65 and 80 °C. ► Carbon corrosion was investigated under the ‘reverse current condition’ in a single cell at operating temperatures of 40, 65 and 80 °C. ► With increasing the operating temperature from 40 to 65 and 80 °C, corrosion of the carbon support and dissolution/migration/agglomeration of Pt catalyst were accelerated resulting in decay in cell performance as well as increases in ohmic and charge transfer resistance and loss of EAS. Effects of operating temperature on performance degradation of polymer electrolyte membrane fuel cells (PEMFCs) were investigated under the repetitive startup/shutdown cycling operation that induced the so-called ‘reverse current condition’. With repeating the startup/shutdown cycle, polarization curves, electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), linear sweep voltammetry (LSV) were measured to examine in situ electrochemical degradation of the MEAs. To investigate physicochemical degradation of the MEAs, scanning electron microscopy (SEM), electron probe micro analysis (EPMA), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR) were employed before and after the startup/shutdown cycling operation. With increasing operating temperature from 40 to 65 and 80 °C under the repetitive reverse-current condition, the cell performance decayed faster since corrosion of the carbon support and dissolution/migration/agglomeration of Pt catalyst were accelerated resulting in increases in ohmic and charge transfer resistance and loss of EAS.