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This study adopts a novel structure design of large-area planar metal-supported solid oxide fuel cell (MS-SOFC), which exhibits the characteristics of self-sealing and high thermal cycling resistance. The self-sealing structure of MS-SOFCs is achieved by brazing technology. Plasma spraying is performed to prepare all functional layers of cells. The size of cells is 10 × 10 cm2. The coefficients of thermal expansion of relevant parts (i.e., porous metal support, interconnector and compound structure of both) and the electrical conductivity of brazing solder were measured. The microstructure of brazing area was observed in situ at 800 °C for 500 h, and the distribution of fuel gas in the interconnector was simulated. The performance of cells was characterized and found that the maximum power density can reach up to 716 mW cm−2 at 700 °C. Moreover, the long-term stability of the cell was investigated for about 500 h with 6 times of thermal cycling implemented during this period. The open circuit voltage and the maximum power density of the cell showed a good stability. [ABSTRACT FROM AUTHOR]

A novel self-sealing structure for metal-supported solid oxide fuel cells (MS-SOFCs) is designed by applying brazing technology between the metal support and interconnector to solve the sealing problem on the anode side of planar SOFCs. A high-reliability self-sealing effect is thus realized at the anode side of the MS-SOFC. Plasma spraying technology is used to prepare cell functional layers including the anode, cathode, and electrolyte. A single cell is assembled with a 50–60-μm plasma-sprayed Sc2O3-stabilized ZrO2 (ScSZ) electrolyte layer. The gas permeability of the self-sealed MS-SOFC without a cathode layer is 0.42 × 10−17 m2. The open-circuit voltage of the cell is ~ 1.1 V in the operating temperature range from 550 to 750 °C. The power density of the cell reaches 1109 mW cm−2 at 750 °C under standard atmosphere. In addition, the use of a fuel gas pressure that is 20 kPa higher than the cathodic gas pressure results in a significant increase in the power density to 1782 mW cm−2 at 750 °C. The novel cell structure and gas tightness of the ScSZ electrolyte prepared by plasma spraying indicates that it can meet the requirements of SOFC applications. [ABSTRACT FROM AUTHOR]

A well-connected and high-porosity current collector layer fabricated at a low temperature of 550 °C is designed for metal-supported solid oxide fuel cells (SOFCs). Reduced Mn 1.5 Co 1.5 O 4 (MCO) powders are used as the binder through the reforming of MCO in the air atmosphere. A high conductivity phase La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3 (LSCF) is added to keep the porous frame microstructure and decease the ohmic polarization of the current collector layer. Three current collector layers are prepared: MCO, MCO/LSCF, and LSCF. The working state of each current collector layer in planar SOFC stack is reproduced by special experimental design; the performance is tested in the range of 550–750 °C. The results show that the current collector layer for SOFC is achieved at low temperatures using the reduction-oxidation properties of MCO, and the performance is improved by adding high conductivity phase LSCF. The gas distribution at the cathode side is also simulated for designing a high performance SOFC. • A high-porosity current collector layer is fabricated at 550°C. • The real working state of the current collector layer is reproduced. • The gas distribution is simulated for designing a current collector layer. [ABSTRACT FROM AUTHOR]

While porous metal-supported solid fuel oxide cells (PMS-SOFCs) have the potential to decrease the cost and increase the start-up speed of power units, the available fabrication processes remain too cumbersome for industrial production. In this study, we prepared bulk-like strontium and magnesium-doped lanthanum gallate (LSGM) coatings using atmospheric plasma spraying (APS) at an increased particle temperature. The large equiaxed grains inside the coatings indicated the epitaxial growth of the splat interfaces and improvement in the coating quality. With increased particle temperature, the conductivity of dense LSGM coatings directly deposited by APS was comparable to that of the bulk material, and cell performance was also significantly enhanced. The maximum power density of the PMS-SOFC at 700 °C was 831 mW cm−2 and 596 mW cm−2 when high and low particle temperatures were used, respectively. These results indicated that the quality of the coating was improved by increasing the in-flight particle temperature. [Display omitted] • LSGM coatings become very dense benefited from the increased particle temperature. • The densification mechanism is from the epitaxial growth of the interfaces. • The conductivity of the LSGM coating is comparable to the bulk from sintering. • The MPD reaches 831 mW cm−2 at 700 °C based on the increased particle temperature. [ABSTRACT FROM AUTHOR]