Analysis of global influencing factors of proton exchange membrane electrolysis cell performance degradation based on digital twin model

Proton exchange membrane water electrolysis is considered one of the most promising technologies for green hydrogen production. However, its performance degradation during long-term operation, which directly affects the economy, durability, and stability of the entire system, has become a critical barrier to its widespread commercial adoption. Therefore, a deep understanding and quantification of the contributions from various influencing factors are essential. In this study, a performance degradation model was established by analyzing the different degradation mechanisms of the components during long-term operation. The global influencing factors affecting the performance degradation of electrolytic cells were summarized, including current density, temperature and cycle load. The digital twin model framework of proton exchange membrane electrolysis cells was proposed, and the multi-physics field coupling effect of the proton exchange membrane electrolysis cells twins was analyzed. After running for 1008 h, the global influencing factors are ranked from high to low in terms of their impact on performance, namely, the number of start-stop times, cycle load (0↔2 A/cm 2 ), high temperature (100℃), high current density (1–2 A/cm 2 ), and low current density (0.1–0.5 A/cm 2 ). Results reveal a significant synergistic effect between global factors. The combined case of high temperature (100°C) and cycle load (0↔2 A/cm 2 , 1-hour interval) induced the most severe performance loss, exhibiting a voltage degradation rate of 320 µV/h after 1008 h. This highlights the critical importance of considering factor interactions in durability assessments. • Digital twin model of proton exchange membrane electrolysis cell constructed and validated. • Cyclic load causes the largest voltage degradation rate among the global influencing factors. • Proton exchange membrane electrolysis cell performance degradation caused by cyclic loading has a higher activation loss ratio. • Proton exchange membrane electrolysis cell performance degradation caused by high temperature has a higher ohmic loss ratio. • Proton exchange membrane electrolysis cell performance degrades as current density increases.