The Effect of Cell Compression and Cathode Pressure on Hydrogen Crossover in PEM Water Electrolysis

verfasst von

Agate Martin, Patrick Trinke, Markus St hler, Andrea St hler, Fabian Scheepers, Boris Bensmann, Marcelo Carmo, Werner Lehnert, Richard Hanke-Rauschenbach

Abstract

Hydrogen crossover poses a crucial issue for polymer electrolyte membrane (PEM) water electrolysers in terms of safe operation and efficiency losses, especially at increased hydrogen pressures. Besides the impact of external operating conditions, the structural properties of the materials also influence the mass transport within the cell. In this study, we provide an analysis of the effect of elevated cathode pressures (up to 15 bar) in addition to increased compression of the membrane electrode assembly on hydrogen crossover and the cell performance, using thin Nafion 212 membranes and current densities up to 3.6 A cm-2. It is shown that a higher compression leads to increased mass transport overpotentials, although the overall cell performance is improved due to the decreased ohmic losses. The mass transport limitations also become visible in enhanced anodic hydrogen contents with increasing compression at high current densities. Moreover, increases in cathode pressure are amplifying the compression effect on hydrogen crossover and mass transport losses. The results indicate that the cell voltage should not be the only criterion for optimizing the system design, but that the material design has to be considered for the reduction of hydrogen crossover in PEM water electrolysis.

Organisationseinheit(en)

Fachgebiet Elektrische Energiespeichersysteme

Externe Organisation(en)

Forschungszentrum Jülich
Queen's University Kingston
Rheinisch-Westfälische Technische Hochschule Aachen (RWTH)

Typ

Artikel

Journal

Journal of the Electrochemical Society

Band

169

ISSN

0013-4651

Publikationsdatum

05.01.2022

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Elektronische, optische und magnetische Materialien, Erneuerbare Energien, Nachhaltigkeit und Umwelt, Oberflächen, Beschichtungen und Folien, Elektrochemie, Werkstoffchemie

Ziele für nachhaltige Entwicklung

SDG 7 – Erschwingliche und saubere Energie

Elektronische Version(en)

https://doi.org/10.1149/1945-7111/ac4459 (Zugang: Offen)