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Direct utilization and internal reforming of gaseous fuels is investigated on symmetric-architecture metal supported solid oxide fuel cells (MS-SOFCs) with thin ceramic electrolyte and scaffold backbone layers, and low cost ferritic stainless steel supports on both sides. Infiltrated Pr-oxide and Ni/samarium-doped ceria catalysts are added to the cathode and anode electrodes, respectively. Initial performance and durability is evaluated for MS-SOFCs operating with natural gas, propane, ammonia, and dimethyl ether at 700 °C. Cells for natural gas and propane utilize a novel high entropy alloy (HEA) catalyst for internal reforming with performance and degradation rates similar to H2 (0.5 W cm−2 and ∼12%/100 h). Initial testing with sulfur shows reversible degradation for levels found in natural gas and irreversible degradation for higher levels found in commercial propane. Overall, MS-SOFCs show successful fuel flexibility.

A solid oxide fuel cell is a high-efficiency power device in hydrogen energy utilization. The durability and dynamic performance of metal-supported solid oxide fuel cells (MS-SOFCs) are superior to those of electrolyte- or electrode-supported cells, with many potential applications. Gadolinium-doped cerium (GDC) has a high oxygen ionic conductivity, making it suitable to act as the electrolyte in MS-SOFCs operating at 500–650 °C. However, the low-temperature sintering of GDC is difficult for MS-SOFCs. In this study, the factors affecting the low-temperature densification of GDC are analyzed based on an orthogonal experimental method. The shrinking rates of 16 experiments are determined. The effects of the particle diameter, pressure of the uniaxial press machine, sintering temperature, and fractions of aid and binder are estimated. The results of a range analysis indicate that the content of sintering aid has the greatest impact on the low-temperature densification of GDC, followed by the powder diameter and the uniaxial pressure. A maximum shrinking rate of 46.99% is achieved with a temperature of 1050 °C. [ABSTRACT FROM AUTHOR]

Metal-supported SOFC consists of metallic and ceramic multilayers. Since the cell has to be flat, interaction between the layers that results in a flat sintered layer needs to be studied. The method used here was changing the starting materials through several experiments. Here, we highlight the effects of pore former in metal slurry on the sintered half-cell multilayer of a 430L metallic support, an NiO-8YSZ anode, and an 8YSZ electrolyte. The results show that by changing the amount of pore former in the 430L metal slurry changed the sinterability of the metal layer. This change of the sinterability of the metal support affected the final warpage state of the cell. This study aid in explaining the sintering phenomena between layers of metal-supported SOFCs. [ABSTRACT FROM AUTHOR]

A solid oxide fuel cell is a high-efficiency power device in hydrogen energy utilization. The durability and dynamic performance of metal-supported solid oxide fuel cells (MS-SOFCs) are superior to those of electrolyte- or electrode-supported cells, with many potential applications. Gadolinium-doped cerium (GDC) has a high oxygen ionic conductivity, making it suitable to act as the electrolyte in MS-SOFCs operating at 500–650 °C. However, the low-temperature sintering of GDC is difficult for MS-SOFCs. In this study, the factors affecting the low-temperature densification of GDC are analyzed based on an orthogonal experimental method. The shrinking rates of 16 experiments are determined. The effects of the particle diameter, pressure of the uniaxial press machine, sintering temperature, and fractions of aid and binder are estimated. The results of a range analysis indicate that the content of sintering aid has the greatest impact on the low-temperature densification of GDC, followed by the powder diameter and the uniaxial pressure. A maximum shrinking rate of 46.99% is achieved with a temperature of 1050 °C.

Combustion synthesis (CS) in thermal explosion mode under conditions of controlled heat loss is used for synthesis of thin Ni-Al porous plates. In the present work, compacted Ni-Al elemental powder mixtures placed between heat-removing clamp plates are heated in a furnace at 25 K/min up to 1000 K under the uniaxial load up to 1.2 MPa with further heat treatment at the temperature of 1100 K. The effects of the Ni/Al mass ratio, reagent powders size, porosity and thickness of the reacting samples as well as conditions of heat-exchange during the CS on the reaction parameters have been studied. Based on the thermocouple measurements, the temperature and timing characteristics of the CS process have been calculated. The phase composition evolution during the process has been analyzed using X-ray diffraction and energy-dispersive X-ray spectroscopy. Special attention has been paid to the study of the following characteristics of synthesized materials: porosity parameters, gas permeability and mechanical properties. Due to the high strength of synthesized materials and formation of relatively homogenous structure with proper pores size and gas permeability, the synthesized porous Ni-Al plates can be considered as good supporting substrate for application in metal-supported solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

Metal supported Solid Oxide Fuel Cells (MS-SOFCs) have attracted considerable interest for their increased robustness and tolerance to redox and thermal cycling and their cheaper production costs. One of the main issue for the development of the MS-SOFC is the integration of the metallic-ceramic electrode onto a metal substrate using cheaper and easily scalable manufacturing techniques. In this study, the integration of a Ni-GDC anode layer on NiCrAl metal support with a porosity higher than 80 vol.% by conventional technique was successfully addressed. A defect free electrode of 5 × 5 cm 2 of dimensions with smoothed surface (necessary for the electrolyte deposition) was obtained through a careful design of the thickness and the composition of the Ni-GDC layers and using (first time for this application) the stencil printing approach. The roughness of the final electrodic layer was comparable to the ones reported for layer deposited on flat/less porous ceramic substrates. [ABSTRACT FROM AUTHOR]

• Anode functional layers for MS-SOC were fabricated by aerosol deposition method. • Optimal anode functional layer composition for fabrication by AD was determined. • Well-bonded nanostructured anode and gas-tight electrolyte were obtained at 1100 °C. • ASR of the half-cell was 0.23 Ohm·cm2 at 577 °C. In order to increase efficiency of metal-supported solid oxide fuel cells (SOFCs) and electrolysis cells (SOECs) and to lower their fabrication and operation temperatures, development of novel methods for the functional layers deposition is of primary importance. In this work, the composite anodes of metal-supported solid oxide cells (MS-SOCs), made of Ni and 10 mol.% scandia and 1 mol.% yttria co-stabilized zirconia (10Sc1YSZ), were deposited by the aerosol deposition (AD) onto high relief porous metal substrates. This step was followed by magnetron sputtering (MSP) of thin 8 mol.% yttria-stabilized zirconia (8YSZ) solid electrolyte. Vacuum co-sintering of the half-cells at 1100 °C resulted in the formation of well-bonded nanostructured anodes and gas-tight electrolyte membranes. The area-specific ohmic resistance of the half-cell in dry hydrogen was 0.23 Ohm·cm2 at 577 °C. [ABSTRACT FROM AUTHOR]