Solid oxide fuel cell numerical study: modified MOLB-type and simple planar geometries with internal reforming

Influence of Interface Morphology on the Thermal Stress Distribution of SOFC under Inhomogeneous Temperature Field

“…It has been found that the temperature gradient in the tubular SOFC is larger than 30 • C/cm when the tube diameter is 1.8 mm [35], while the temperature gradient is smaller than 5 • C/cm when the tube diameter is larger than 15 mm [36,37]. In recent years, compared with traditional planar SOFC, the corrugated SOFC has received a lot of attention because it has higher fuel utilization, lower temperature differences and higher current density [38][39][40][41][42][43] by enlarging the triple phase boundary length of the cell [44,45]. Similar to typical planar SOFC, the anode-supported corrugated SOFC consists of three components, i.e., anode, cathode and electrolyte, and is a dense film of only a few tens of microns thick or even thinner, but the interfaces between electrodes and the electrolyte are corrugated rather than flat [15,46].…”

Detailed comparison of the performance between a simple and a modified mono-block-layer-built type solid oxide fuel cell

“…The results showed that the biogas from local sludge had the lower temperature gradient and more homogeneous current density distributions along the fuel cell, on the other hand, with the new configuration proposed for the MOLB-type geometry the temperature distribution inside of the fuel cell had lower temperature gradients. Ramírez et al [24] compared a modified MOLB-type SOFC with a porous embedding pipe in the air side of the geometry and a simple planar geometry feeding by biogas from local sludge considering internal reforming of methane in the anode side. They found higher H 2 concentration and lower average temperature value from the MOLB-type with embedding porous pipe geometry, which help to handle higher current densities, to reduce thermal stress and to increase the performance of the fuel cell.…”

“…They found higher H 2 concentration and lower average temperature value from the MOLB-type with embedding porous pipe geometry, which help to handle higher current densities, to reduce thermal stress and to increase the performance of the fuel cell. It is necessary to highlight that in the previous investigation [23] and [24] the authors only considered an average current density of 2,000 A/m 2 for the different cases and they used mainly biogas to feed the SOFC. And, as it is well known, the higher temperature gradients inside the SOFCs are reached when the hydrogen is used as a fuel [20,22]; in consequence, the thermal stresses are an important issues in the materials of the SOFC.…”

“…And, as it is well known, the higher temperature gradients inside the SOFCs are reached when the hydrogen is used as a fuel [20,22]; in consequence, the thermal stresses are an important issues in the materials of the SOFC. Therefore, the objective of this study is to complement the analysis made in Ramirez et al [23,24], in a detail way, it means, obtaining the performance of a simple MOLB-type geometry and comparing it with a cell that has a porous pipe embedded in the air channel with constant and variable porosity along the porous pipe in the geometry, using hydrogen as fuel and considering different current densities. To achieve this objective, four cases are analyzed: a) without the porous pipe, b) with a pipe of constant porosity, c) with two different porosities and d) with four variable porosities.…”

Crack propagation of planar and corrugated solid oxide fuel cells during cooling process

“…[1][2][3][4] The main types of SOFCs are planar and tubular, of which planar type is more common. With the deeper investigation on structural optimization of SOFC, corrugated SOFC has attracted much attention because of its higher fuel utilization and power density, [5][6][7][8][9][10] and it processes these advantages by increasing triple-phase boundary (TPB) length compared with that of conventional planar SOFC. 11,12 However, at present, all types of SOFC are faced with the challenges of stability and durability except for electrochemical performance prior to commercialization, especially the failure of electrolyte and interfacial delamination between electrodes and electrolyte caused by thermal stress during thermal cycle.…”