Development of a one-dimensional dynamic model of proton exchange membrane electrolysis cell

Abstract

Proton exchange membrane water electrolysis is a key technology for hydrogen production, particularly when powered by renewable energy. To ensure operational stability under fluctuating power inputs, this study develops a one-dimensional dynamic model of a cell. Unlike previous models that primarily focus on steady-state behavior or empirical tuning, the proposed model integrates mass, momentum, and energy conservation equations across eight distinct control volumes―including the bipolar plate, porous transport layers (PTLs), micro porous layer (MPL), catalyst layers, and membrane―capturing the coupled effects of two-phase flow and transient thermal behavior in a physically rigorous manner. The model accurately predicts the dynamic voltage response, including overshoot and undershoot behaviors, during step and ramp current transients, with temperature identified as the dominant factor influencing voltage dynamics, while gas saturation and pressure have secondary effects. Validation against experimental data yielded a mean absolute voltage error of 5.3 mV at steady state and accurately predicted voltage overshoot and undershoot responses under dynamic loading conditions. This developed model is applicable for real-time digital twin applications or analyzing performance variations based on the internal physical structure of the cell.