Advanced

Effect of the electrochemical active site on thermal stress in solid oxide fuel cells

Zeng, Shumao; Yu, Guangsen; Parbey, Joseph; Song, Di; Li, Tingshuai and Andersson, Martin LU (2018) In Journal of the Electrochemical Society 165(2). p.105-113
Abstract

A 3D model is developed by coupling the equations for momentum, gas-phase species, heat, electron and ion transport to analyze cell polarization, current density and temperature in solid oxide fuel cells (SOFCs). The increase of active sites is beneficial to improve efficiency of electrochemical reactions, but it can be also detrimental to SOFCs’ stability as it will induce changes in strength and distribution of the thermal stresses. The variation of thermal stresses is systematically studied by grading the active site along the main flow direction. The results indicate that the first principle stress increases with the active site at the interface of electrolyte and electrode, but the shear stress mainly appears in the vicinity of gas... (More)

A 3D model is developed by coupling the equations for momentum, gas-phase species, heat, electron and ion transport to analyze cell polarization, current density and temperature in solid oxide fuel cells (SOFCs). The increase of active sites is beneficial to improve efficiency of electrochemical reactions, but it can be also detrimental to SOFCs’ stability as it will induce changes in strength and distribution of the thermal stresses. The variation of thermal stresses is systematically studied by grading the active site along the main flow direction. The results indicate that the first principle stress increases with the active site at the interface of electrolyte and electrode, but the shear stress mainly appears in the vicinity of gas inlets, which both suffer from a dramatic change when the active site is enhanced from the initial state to 1.5 times. Moreover, the electrolyte is subjected to large contrary tensile stresses, and the first principle stress is responsible for crack possibly occurring to the electrolyte. We also confirm that the sharp fluctuation of stress caused by the active sites can be relieved through adjusting thickness of the anode active layer.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of the Electrochemical Society
volume
165
issue
2
pages
105 - 113
publisher
The Electrochemical Society
external identifiers
  • scopus:85048569311
ISSN
0013-4651
DOI
10.1149/2.1341802jes
language
English
LU publication?
yes
id
46b79145-5dc3-4270-93cb-3b7046ce620c
date added to LUP
2018-07-03 10:30:21
date last changed
2019-01-06 13:59:00
@article{46b79145-5dc3-4270-93cb-3b7046ce620c,
  abstract     = {<p>A 3D model is developed by coupling the equations for momentum, gas-phase species, heat, electron and ion transport to analyze cell polarization, current density and temperature in solid oxide fuel cells (SOFCs). The increase of active sites is beneficial to improve efficiency of electrochemical reactions, but it can be also detrimental to SOFCs’ stability as it will induce changes in strength and distribution of the thermal stresses. The variation of thermal stresses is systematically studied by grading the active site along the main flow direction. The results indicate that the first principle stress increases with the active site at the interface of electrolyte and electrode, but the shear stress mainly appears in the vicinity of gas inlets, which both suffer from a dramatic change when the active site is enhanced from the initial state to 1.5 times. Moreover, the electrolyte is subjected to large contrary tensile stresses, and the first principle stress is responsible for crack possibly occurring to the electrolyte. We also confirm that the sharp fluctuation of stress caused by the active sites can be relieved through adjusting thickness of the anode active layer.</p>},
  author       = {Zeng, Shumao and Yu, Guangsen and Parbey, Joseph and Song, Di and Li, Tingshuai and Andersson, Martin},
  issn         = {0013-4651},
  language     = {eng},
  month        = {01},
  number       = {2},
  pages        = {105--113},
  publisher    = {The Electrochemical Society},
  series       = {Journal of the Electrochemical Society},
  title        = {Effect of the electrochemical active site on thermal stress in solid oxide fuel cells},
  url          = {http://dx.doi.org/10.1149/2.1341802jes},
  volume       = {165},
  year         = {2018},
}