Rinasa Agistya Anugrah, Yosef Budiman, Agus Widyianto, Fungky Dyan Pertiwi, Sanupal Muzamil
Proton exchange membrane fuel cells (PEMFCs) have attracted significant research interest. However, many numerical models employ generic membrane assumptions that do not accurately capture the behavior of high-temperature PEMFCs (HT-PEMFCs). This limitation can undermine the reliability of predicted electrical generation and thermal gradients, both of which are essential for performance optimization and stable operation. To address this gap, a material-consistent computational fluid dynamics (CFD) multiphysics model was developed for a single-channel polybenzimidazole (PBI)-based HT-PEMFC. The model systematically evaluated the coupled effects of hydrogen–oxygen stoichiometry and operating temperature on electro-thermal performance. Using the validated finest mesh, stoichiometry ratios (ξ = 1.2 – 1.73) were examined across low-operating temperature (323.15 K) and high-operating temperature (393.15 – 473.15 K) through polarization and power-density analyses. The results show that, at the low-temperature condition of 323.15 K, the optimum stoichiometric ratio was ξ = 1.46, which produced the highest power density and was supported by a stronger thermal response in the active region, indicating more effective energy conversion under limited thermal input. Meanwhile, the lean condition (ξ = 1.2) consistently yielded the most favorable voltage–current density trade-off and the highest power-density profile at ≥ 413.15 K. Internal parameter diagnostics supported these findings and identified dehydration-driven limitations at extremely high temperatures. Although operation at 473.15 K reduced the heat-loss percentage and increased electrical output, it also increased thermal intensity without a proportional improvement in performance, indicating diminishing returns. These results enhance understanding of the coupled effects of reactant stoichiometry and operating temperature on the electro-thermal behavior of HT-PEMFC systems. The recommended condition for practical high-temperature operation is ξ = 1.2 at 453.15 K, which achieves an optimal balance between electrical output, minimized heat loss, and improved thermal uniformity. © 2026 The Authors.
Department of Automotive Engineering Technology, Universitas Muhammadiyah Yogyakarta, Yogyakarta, 55183, Indonesia; Automotive Engineering and Manufacturing Research Group, Universitas Negeri Yogyakarta, Yogyakarta, 55651, Indonesia; PT Sahla Inovatif Teknik, Yogyakarta, 55581, Indonesia; Department of Mechanical and Automotive Engineering, Universitas Negeri Yogyakarta 55651, Indonesia; Department of Mechanical Engineering, Universitas Muhammadiyah Magelang, Magelang, 59214, Indonesia; Department of Electro-Medical Technology, Universitas Muhammadiyah Yogyakarta, Yogyakarta, 55183, Indonesia
