Numerical study of gas crossover effect on hydrogen-oxygen proton exchange membrane fuel cell

• Published in: International journal of heat and mass transfer 2024-12, Vol.234, p.126060, Article 126060
• Main Authors: Tao, Hengyang, Yang, Kai, Wang, Bowen, Hou, Ben, Wu, Kangcheng, Qin, Zhikun, Luo, Bangyao, Kang, Jiawei, Du, Qing, Jiao, Kui
• Format: Article
• Language: English
• Subjects: Gas crossover; Hydrogen-oxygen PEMFC; Numerical analysis; Open-circuit voltage
• ISSN: 0017-9310
• DOI: 10.1016/j.ijheatmasstransfer.2024.126060

•A quasi-two-dimensional model of H2/O2 PEMFC considering gas crossover is developed.•Gas crossover effect is obvious in the low current density region.•Increasing temperature and relative humidity will decrease OCV.•Increasing inlet pressure only slightly increases OCV considering gas crossover.•OCV increases slightly when the membrane thickness is greater than 75 μm. Hydrogen-oxygen proton exchange membrane fuel cell (H2/O2 PEMFC) is a typical fuel cell for the applications of air-free environments, such as aerospace and underwater. Gas crossover has an adverse effect on the cell performance especially on open-circuit voltage (OCV), and this phenomenon would be severe for H2/O2 PEMFC. In this study, we develop a H2/O2 PEMFC model considering hydrogen and oxygen crossover, and investigate the gas crossover effect on H2/O2 PEMFC, and effects of temperature, relative humidity, inlet pressure and membrane thickness. The numerical results show that the gas crossover effect on the cell performance is obvious in the low current density region, and this effect becomes weak with current density. Although the crossover flux rate of hydrogen is generally greater than that of oxygen, the crossover current density of oxygen could be greater than that of hydrogen. Increasing temperature and relative humidity will decrease the OCV, and increase hydrogen and oxygen crossover current density. The temperature effect on OCV is more obvious at high relative humidity conditions. Increasing inlet pressure only slightly increases the OCV with considering the gas crossover effect. The OCV increases with increasing membrane thickness, and this positive effect becomes weak when the membrane thickness is greater than 75 μm in the investigated range. The work illustrates the basic influence rules and some quantified results of the critical parameters on the gas crossover effect and OCV of H2/O2 PEMFC.