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DOE OSTI · 3014972

Mitigating Electrochemical Impedance Spectroscopy Artifacts in PEMWE Reference Electrode Measurements

Buehre, Lena V. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:000000028555703X)·Hansen, Kentaro U. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000175191655)·Henckel, Danielle [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000326407127)·Le, Giang [Electric Hydrogen, Devens, MA (United States)] (ORCID:0000000162504472)·Padgett, Elliot [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000190342335)·Bender, Guido [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000337774707)
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Abstract

This study investigates strategies to improve the quality of electrochemical impedance spectroscopy (EIS) measurements using reference electrodes (RE) in proton exchange membrane water electrolyzers (PEMWE). We demonstrate that adding a low impedance wire in parallel to the RE significantly enhances signal accuracy, especially at high frequencies. Additionally, we identify electrical pad heaters as a source of measurement noise. EIS measurements fulfilling Kramers–Kronig validity criteria were only achieved in their absence. These insights advance the diagnostic capabilities of REs in water electrolyzers and support more reliable, spatially resolved analysis of electrochemical losses within the cell.

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08 HYDROGEN37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYelectrochemistryelectrolysishydrogenimpedance spectroscopyreference electrode

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Buehre, Lena V. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:000000028555703X), Hansen, Kentaro U. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000175191655), Henckel, Danielle [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000326407127), Le, Giang [Electric Hydrogen, Devens, MA (United States)] (ORCID:0000000162504472), Padgett, Elliot [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000190342335), Bender, Guido [National Renewable Energy Laboratory (NREL), Golden, CO (United States)] (ORCID:0000000337774707). 2025-11-25. Mitigating Electrochemical Impedance Spectroscopy Artifacts in PEMWE Reference Electrode Measurements. https://doi.org/10.1149/2754-2734%2Fae1f29

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