Local current density and electrochemical impedance measurements within 50 cm single-channel PEM electrolysis cell

authored by

Christoph Immerz, Boris Bensmann, Patrick Trinke, Michel Suermann, Richard Hanke-Rauschenbach

Abstract

The present analysis shows the local distribution of current density and EIS measurements along a 50 cm single-channel proton exchange membrane water electrolysis (PEMWE) cell. Measurements for operating modes with one sufficiently high and one insufficiently low stoichiometric water ratio (λ) were carried out to observe effects on the current density distribution. Furthermore, global and local EIS measurements were performed to distinguish between the cell voltage loss differences in the two cases. The mass transport losses η _mtx and the Ohmic voltage losses η show a strong increase, when the stoichiometric water ratio falls below a level of λ ≈ 5. The reduction of the inlet water flux of the anode reduces both the proton conductivity of the ionomer within the catalyst layer and the membrane, increasing transport and Ohmic resistances, respectively. The local analysis has shown that the level of membrane and catalyst hydration under low stoichiometric conditions can be distributed highly non-homogeneous in along-the-channel direction, with the most pronounced dehydration toward the end of the channel.

Organisation(s)

Institute of Electric Power Systems
Section Electrical Energy Storage Systems

Type

Article

Journal

Journal of the Electrochemical Society

Volume

165

Pages

F1292-F1299

ISSN

0013-4651

Publication date

12.12.2018

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Electronic, Optical and Magnetic Materials, Renewable Energy, Sustainability and the Environment, Surfaces, Coatings and Films, Electrochemistry, Materials Chemistry

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy

Electronic version(s)

https://doi.org/10.1149/2.0411816jes (Access: Closed)
https://doi.org/10.15488/4911 (Access: Open)