Residual stress analysis of a micro-tubular solid oxide fuel cell

Abstract

Available online xxxKeywords: Micro-tubular solid oxide fuel cell (MT-SOFC) Residual stress Electrode thickness Failure probability a b s t r a c t A two-dimensional axisymmetric micro-tubular solid oxide fuel cell (MT-SOFC) model is developed to study the influence of component (anode, cathode or electrolyte) thickness onresidual stress at the room temperature. The results show that the anode is mainly subjected to tension stress while electrolyte and cathode are mostly exposed to compressive stress. However, the stress in a component can be reduced by increasing its thickness with other components unchanged. Then the Weibull analysis method is adopted to calculate the failure probability of the anode, it is found that the anode is prone to failure with a thinner anode or thicker cathode and electrolyte; the electrolyte thickness has a more significant effect on the anode failure probability than the cathode; and the component thickness must be coordinated in order to maximize the mechanical performance. The formula of the minimum anode thickness under the failure probability criterion 1E-6 is given, which brings considerable convenience to the design of MT-SOFC.

Influence of Anode Functional Layers on Electrochemical Performance and Mechanical Strength in Microtubular Solid Oxide Fuel Cells Fabricated by Gel-Casting

“…From the cathode effect point of view, MOR for the cell-1 is very close to that reported for an half-cell with identical electrolyte and support, and an AFL of slightly smaller thickness (36). Taking into account this comparative, the cathode influence on the flexural strength of cell is quite limited, which is in concordance with the results of other works (77,78,79). In conclusion, the mechanical strength for the studied cells with AFLs may be suitable for their implementation in robust stacks (6,37,38).…”

“…It may be attributed to the thermomechanical stress generated between the electrolyte layer and support, during the cosintering, NiO reduction, and in operation. As concluded in previous works, (77,78,79) the support composition has a significant influence on its thermo-mechanical…”

A computational fluid dynamics and finite element analysis design of a microtubular solid oxide fuel cell stack for fixed wing mini unmanned aerial vehicles

“…The counter flow configuration yielded 8.23 % higher current density, but the co-flow configuration shown 22.58 % higher efficiency. Kong et al [50] developed a two-dimensional axisymmetric microtubular SOFC model to study the influence of electrode thickness on residual stresses inside the fuel cell at room temperature. The results predicted that the anode was exposed to tension stress whereas the electrolyte and the cathode were exposed to compressive stress.…”

Numerical study of detecting crack initiation in a planar solid oxide fuel cell

“…[4][5][6][7][8][9][10] Unfortunately, the high-temperature operation of SOFCs has several drawbacks such as limited material selection, accelerated morphological and chemical degradation, and enhanced diffusion of components and impurities between adjacent layers and on the surface. Most researchers nowadays focus on the thermal stress inside the SOFC, [11][12][13][14] They studied the delamination and degradation of SOFCs electrode/electrolyte estimated by calculating the stresses generated within the different layers of the cell. 11 Luo et al studied the effects of anode porosity on thermal stress and failure probability of planar SOFC with bonded compliant seal by finite element method (FEM) and showed discontinuous stresses along the plate thickness which was due to the mismatching of material properties.…”