Reversible Degradation Phenomenon in PEMWE Cells

An Experimental and Modeling Study

authored by: Tobias Krenz, Alexander Rex, Lennard Helmers, Patrick Trinke, Boris Bensmann, Richard Hanke-Rauschenbach
Abstract: In proton exchange membrane water electrolysis (PEMWE) systems, voltage cycles dropping below a threshold are associated with reversible performance improvements, which remain poorly understood despite being documented in literature. The distinction between reversible and irreversible performance changes is crucial for accurate degradation assessments. One approach in literature to explain this behavior is the oxidation and reduction of iridium. Iridium-based electrocatalyst activity and stability in PEMWE hinge on their oxidation state, influenced by the applied voltage. Yet, full-cell PEMWE dynamic performance remains underexplored, with a focus typically on stability rather than activity. This study systematically investigates reversible performance behavior in PEMWE cells using Ir-black as an anodic catalyst. Results reveal a recovery effect when the low voltage level drops below 1.5 V, with further enhancements observed as the voltage decreases, even with a short holding time of 0.1 s. This reversible recovery is primarily driven by improved anode reaction kinetics, likely due to changing iridium oxidation states, and is supported by alignment between the experimental data and a dynamic model that links iridium oxidation/reduction processes to performance metrics. This model allows distinguishing between reversible and irreversible effects and enables the derivation of optimized operation schemes utilizing the recovery effect.
Organisation(s): Section Electrical Energy Storage Systems
External Organisation(s): Siemens AG
Type: Article
Journal: Journal of the Electrochemical Society
Volume: 171
ISSN: 0013-4651
Publication date: 09.12.2024
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Electronic, Optical and Magnetic Materials, Renewable Energy, Sustainability and the Environment, Condensed Matter Physics, Surfaces, Coatings and Films, Electrochemistry, Materials Chemistry
Sustainable Development Goals: SDG 7 - Affordable and Clean Energy
Electronic version(s): https://doi.org/10.1149/1945-7111/ad96e4 (Access: Open)

BibTeX

@article{a4984175b6bc4e0db72c3ded40b04d01,
title = "Reversible Degradation Phenomenon in PEMWE Cells: An Experimental and Modeling Study",
abstract = "In proton exchange membrane water electrolysis (PEMWE) systems, voltage cycles dropping below a threshold are associated with reversible performance improvements, which remain poorly understood despite being documented in literature. The distinction between reversible and irreversible performance changes is crucial for accurate degradation assessments. One approach in literature to explain this behavior is the oxidation and reduction of iridium. Iridium-based electrocatalyst activity and stability in PEMWE hinge on their oxidation state, influenced by the applied voltage. Yet, full-cell PEMWE dynamic performance remains underexplored, with a focus typically on stability rather than activity. This study systematically investigates reversible performance behavior in PEMWE cells using Ir-black as an anodic catalyst. Results reveal a recovery effect when the low voltage level drops below 1.5 V, with further enhancements observed as the voltage decreases, even with a short holding time of 0.1 s. This reversible recovery is primarily driven by improved anode reaction kinetics, likely due to changing iridium oxidation states, and is supported by alignment between the experimental data and a dynamic model that links iridium oxidation/reduction processes to performance metrics. This model allows distinguishing between reversible and irreversible effects and enables the derivation of optimized operation schemes utilizing the recovery effect.",
keywords = "Electrode Kinetics, PEM Water Electrolysis, Reversible Degradation",
author = "Tobias Krenz and Alexander Rex and Lennard Helmers and Patrick Trinke and Boris Bensmann and Richard Hanke-Rauschenbach",
note = "Publisher Copyright: {\textcopyright} 2024 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited.",
year = "2024",
month = dec,
day = "9",
doi = "10.1149/1945-7111/ad96e4",
language = "English",
volume = "171",
journal = "Journal of the Electrochemical Society",
issn = "0013-4651",
publisher = "Electrochemical Society, Inc.",
number = "12",
}