Effects of Relative Humidification on Durability of Membrane Electrode Assembly of Proton Exchange Membrane Fuel Cells. Issue 6 (14th June 2021)

• Record Type: Journal Article
• Authors: Hong, Kang; Li, Shang; Zhu, Kai; Pang, Jin; Liu, Shengchu; Wang, Ruyi; Pan, Mu
• Is Part Of: Journal of the Electrochemical Society. Volume 168:Issue 6(2021)
• Publication Date: 2021-06-14
• Subjects: Electrochemistry -- Periodicals; 541.3705
• DOI: 10.1149/1945-7111/ac0760
• Languages: English
• ISSNs: 0013-4651

Abstract

Abstract : Membrane electrode assembly (MEA) is a core component of fuel cells, and its durability constitutes the bottleneck of fuel cells commercialization. In this paper, the effects of relative humidification (RH) on durability of membrane electrode assembly (MEA) are studied by the limiting current method. In-situ durability tests are carried out for 2040 h under constant current density of 800 mA cm −2 and relative humidification (RH) of 70%. The results are then compared to those of our previously published 1465h-MEA obtained for 1465 h under 100% humidification. The degradation in the voltage during the process is analyzed, and degradation mechanisms are investigated by electrochemical impedance spectroscopy and limiting current methods to analyze the change in oxygen transport resistance of the gas diffusion layer. The data suggest that the decline in the humidification can greatly improve the durability of MEAs, especially from 0 to 1000 h. The voltage decay rate of 2040h-MEA is half that of 1465h-MEA. The main degradation occurs in the substrate layer after durability tests for 2040 h under 70%RH. By comparison, 1465h-MEA operating at 100% RH shows a serious decay not only in the substrate layer but also in the MPL, as confirmed by the changes in contact angles.