Experimental Testing of PEM Electrolyzer Degradation
Author
Bermudez Blanco, Javier
Term
3. term
Education
Publication year
2025
Submitted on
2025-12-16
Pages
57
Abstract
Green hydrogen is a key option for storing renewable energy. Proton exchange membrane (PEM) electrolyzers, which split water into hydrogen and oxygen, are among the most promising devices, but their performance declines over time. This project examined how PEM electrolyzers degrade under controlled laboratory conditions. Manually assembled test cells were operated for extended periods on a Greenlight Innovation test station. An internal electrical short circuit was present throughout the experiments, which compromised the measurements; it was identified and corrected only at the end. The study distinguished reversible from irreversible degradation. The electrolyzer reached peak performance after 264 hours of operation, followed by a decline due to degradation. Irreversible losses were linked to chemical degradation of the ionomer (the ion‑conducting binder), passivation of the porous transport layers (PTLs that move water and gases), catalyst dissolution, and carbon corrosion. Higher temperatures improved performance, whereas changes in water flow rate and pressure had little effect. Reversible losses, mainly from gas bubble accumulation, were consistently observed and could be recovered by shutting the system down. A stress test confirmed that carbon‑based PTLs are incompatible with the oxygen evolution reaction (OER) at the anode.
Grøn brint er en vigtig mulighed for at lagre vedvarende energi. PEM‑elektrolysatorer (protonudvekslingsmembran), som spalter vand til brint og ilt, er blandt de mest lovende teknologier, men deres ydelse falder over tid. Dette projekt undersøgte, hvordan PEM‑elektrolysatorer nedbrydes under kontrollerede laboratorieforhold. Manuelt samlede testceller blev kørt i lange perioder på en Greenlight Innovation teststation. En intern elektrisk kortslutning var til stede under hele forsøgsforløbet, hvilket forringede målingerne; den blev først identificeret og udbedret ved afslutningen. Studiet skelnede mellem reversible og irreversible nedbrydningsprocesser. Elektrolysatoren nåede en ydelsestop efter 264 timers drift, hvorefter effektiviteten faldt på grund af nedbrydning. Irreversible tab blev knyttet til kemisk nedbrydning af ionomeren (den ionledende binder), passivering af de porøse transportlag (PTL, der leder vand og gasser), katalysatoropløsning og korrosion af kulstof. Højere temperaturer forbedrede ydelsen, mens ændringer i vandgennemstrømning og tryk havde ringe betydning. Reversible tab, primært forårsaget af ophobning af gasbobler, dukkede gentagne gange op og kunne genvindes ved at slukke systemet. En stresstest viste, at kulstofbaserede PTL er uforenelige med oxygenudviklingsreaktionen (OER) på anodesiden.
[This apstract has been rewritten with the help of AI based on the project's original abstract]
Keywords