Microstructure-Based Modeling of Inner Oxygen Pressure in Solid Oxide Electrolysis Cells

Conference · Tue Oct 08 04:00:00 EDT 2024

DOI:https://doi.org/10.2172/2468782· OSTI ID:2468782

Xue, Fei ^[1]; Lei, Yinkai ^[1]; Cheng, Tianle ^[1]; Yang, Tao ^[1]; Epting, William ^[2]; Abernathy, Harry ^[2]; Wen, Youhai ^[2]

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1. NETL Site Support Contractor, National Energy Technology Laboratory
2. NETL

One major degradation mechanism during long-term operation of solid oxide electrolysis cells (SOECs) is delamination of oxygen electrodes (OEs). The driving force for the electrode delamination could be the generated high inner oxygen pressure near the electrode-electrolyte interface during operation. However, the effects of transport properties and electrode thickness on the inner oxygen partial pressure are not well understood. Here, a microstructure-based electrochemical model which includes the conduction of electrons and oxygen ions coupled with Butler-Volmer-type chemical reactions at triple-phase-boundaries (TPBs), is employed to investigate the oxygen pressure in lanthanum strontium manganate (LSM)-based SOECs. The model is applied to both two-dimensional (2D) prototype microstructures and three-dimensional (3D) realistic microstructures, and the oxygen pressure is analyzed as a function of transport properties and electrode thickness under both potentiostatic and galvanostatic operations. The simulation results suggest strategies to suppress electrode delamination. The simulation results are compared to an analytical solution, and the discrepancies are attributed to the Butler-Volmer-type kinetics included in the microstructure-based model.

• Research Organization: National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV, and Albany, OR (United States)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• OSTI ID: 2468782
• Country of Publication: United States
• Language: English