Title: Theoretical Analysis of Critical Conditions for Crack Formation and Propagation, and Optimal Operation of SOECs

Abstract

A theoretical analysis on crack formation and propagation was performed based on the coupling between the electrochemical process, classical elasticity, and fracture mechanics. The chemical potential of oxygen, thus oxygen partial pressure, at the oxygen electrode-electrolyte interface ( ${\mu }_{O_2}^{\mathit{OE\mid El}}$ ) was investigated as a function of transport properties, electrolyte thickness and operating conditions (e.g., steam concentration, constant current, and constant voltage). Our analysis shows that: a lower ionic area specific resistance (ASR), $r_i^{OE},$ and a higher electronic ASR ( $r_e^{OE}$ ) of the oxygen electrode/electrolyte interface are in favor of suppressing crack formation. The ${\mu }_{O_2}^{OE\mid El},$ thus local pO ₂ , are sensitive towards the operating parameters under galvanostatic or potentiostatic electrolysis. Constant current density electrolysis provides better robustness, especially at a high current density with a high steam content. While constant voltage electrolysis leads to greater variations of ${\mu }_{O_2}^{OE\mid El}.$ Constant current electrolysis, however, is not suitable for an unstable oxygen electrode because ${\mu }_{O_2}^{OE\mid El}$ can reach a very high value with a gradually increased $r_i^{OE}.$ A crack may only occur under certain conditions when $p_{O_2}^{TPB}>p_{cr}.$

Authors:

Wang, Yudong ;

• Search DOE PAGES for author "Wang, Yudong"
• Search DOE PAGES for ORCID "0000-0002-3496-5076"

Virkar, Anil V.; Khonsari, M. M.; Zhou, Xiao-Dong

• Search DOE PAGES for author "Zhou, Xiao-Dong"
• Search DOE PAGES for ORCID "0000-0001-9934-9429"

Publication Date:

Thu Apr 28 00:00:00 EDT 2022

Research Org.:

University of Louisiana, Lafayette, LA (United States)

Sponsoring Org.:

USDOE Office of Fossil Energy (FE); National Science Foundation (NSF)

OSTI Identifier:

2325467

Alternate Identifier(s):

OSTI ID: 1856067; OSTI ID: 1980875

Grant/Contract Number:  

FE-0032110; FE0032110; NSF-1742696; NSF-1946231; NSF-2119688

Resource Type:

Published Article

Journal Name:

Journal of the Electrochemical Society

Additional Journal Information:

Journal Name: Journal of the Electrochemical Society Journal Volume: 169 Journal Issue: 4; Journal ID: ISSN 0013-4651

Publisher:

The Electrochemical Society

Country of Publication:

United States

Language:

English

Subject:

42 ENGINEERING