Modelling for Resilient HT-PEM Fuel Cells

High-temperature proton exchange membrane fuel cells (HT-PEMFCs) are a promising hydrogen technology. Their operation at 160–180 °C enables simple heat management and improved tolerance to fuel impurities.

In HT-PEMFCs, the polymer-bound phosphoric acid electrolyte (PA) enables proton conduction. During cell operation, PA is gradually lost or redistributed, resulting in decreased conductivity, reduced catalyst utilisation, and long-term performance decline. To improve HT-PEMFC performance, the MEAsureD project aims to develop novel ion-pair polymers with increased PA retention capacity.

Understanding Phosphoric Acid Leaching

Currently, no established model links the interaction between membrane polymer and phosphoric acid with water-transport-induced acid leaching. PA degradation models developed by UL aim to improve understanding of acid loss and how it can be mitigated through improved material selection, operating conditions, and cell design.

Interpreting FC State of Health

Physics-based FC operation modelling connects easily measurable data, such as polarisation curves or electrochemical impedance spectra, with hidden FC internal states. During the MEAsureD project, UL developed a novel HT-specific fuel cell operation model that combines these two data sets in order to better estimate physical model parameters associated with the rate and efficiency of reactions, as well as transport mechanisms. This opens new perspectives for more accurate fuel cell monitoring and diagnostics.

Furthermore, the newly developed parameter sensitivity analysis shows which physical parameters have the strongest influence on cell operation and how confidently they can be identified from available measurements. This is essential for reliable FC state-of-health assessment.

From Local States to Full-Cell Behaviour

In fuel cells, temperature, humidity, current density, and gas concentrations can vary significantly across the active area, creating local regions where degradation may accelerate.

AVL’s newly developed 3D-resolved HT-PEMFC operation model, which is part of the AVL FIRE™ M suite, captures these spatial variations and, by interfacing with UL’s HT-PEM degradation modelling framework, provides insight into how cell design, flow-field configuration, and operating strategy influence performance and durability.

Towards Durable Hydrogen Technology

During the MEAsureD project, these modelling activities support better diagnostics, improved design, and more reliable lifetime prediction, embedding HT-PEM fuel cells into Europe’s hydrogen economy.