Anode-supported single cells

Figure 4. Current-voltage curves for 50 50 mm anode-supported single cells with a YSZ electrolyte applied by sol-gel technique and with an LSCF-type cathode as a function of the temperature (fuel gas H2 (3% H2O) = 1000 ml/min, oxidant air = 1000 ml/min).

Figure 9.16 Current density (700 mV) at 600, 650, and 700 °C of tested anode-supported single cells with an LSC cathode as function of sintering temperature.

In the following, a physicochemical ECM for anode-supported single cells (ASCs) with thin-film electrolyte, developed at Forschungszentrum Jiihch (FZJ), is presented. 

Figure 33.1 Photographs of anode-supported single cell and its microstructure.

Fig. 4 Electrochemical performance for an optimized anode-supported single cell measured at 600, 700, and 800 °C [31]...

Sprenkle et al. [73] Single anode-supported button cell 750... 

The suitability of lanthanum nickelate as an SOFC cathode has been examined by Virkar s group [138], They showed that LN performed poorly as a single-phase cathode in an anode-supported YSZ cell. However, with an SDC/LN composite interlayer the performance of the LN cathode increased substantially and the maximum power density of the cell with a YSZ thin electrolyte (-8 pm) was -2.2 Wear2 at 800°C, considerably higher than 0.3 to 0.4 Wcm-2 of similar cells with only LN or SDC interlayer. The results are significant as it shows that the composite MIEC cathodes perform much better than single-phase MIEC in the case of LN despite its mixed ionic and electronic conductivity. 

Suzuki, T., Jasinski, P., Petrovsky, V., Anderson, H., and Dogan, F. Anode Supported Single Chamber Solid Oxide Fuel Cell in CH4-air Mixture, Journal of the Electrochem. Soc., 151, A1473 (2004). 

Farhad and Hamdullahpur (2010) propose a novel portable fuel cell plant fueled by ammonia. In this plant a solid-oxide fuel cell (SOFC) stack consisting of anode-supported planar cells with an Ni-YSZ anode, YSZ electrolyte, and YSZ-LSM cathode is used to generate electric power. An ammonia cylinder with a capacity of 0.8 L is sufficient to sustain full-load operation of the portable system for 9 hours and 34 minutes. Computer simulation of this system predicts that for a 100-W portable device operating at a voltage of 25.6 V (a single-cell voltage of 0.73 V), an energy efficiency of 41.1% and a fuel utilization ratio of 80% are attainable. 

Planar SOFCs of various sizes have been fabricated and operated under various conditions. Single cells have been shown to have extraordinarily high areal power densities. For example, power densities of up to 1.8 W/cm at 800°C and 0.8 W/cm at 650°C have been obtained for anode-supported planar cells with hydrogen fuel and air oxidant (Figure 8.9) [20]. 

In the present work, we report results on the fabrication and performance of anode-supported, thin SDC el trolyte fuel cells operated in a single chamber configuration where methane and oxygen served as the gas mixture. 

PLD has also been utilized to produce bilayer electrolytes. In one study, aNiO-YSZ (anode support, tape cast)/NiO-SDC (AFL, screen-printed)/ScSZ-SDC (electrolyte bilayer, PLD)/SSC (cathode, screen-printed) cell showed excellent performance (0.5 and 0.9 W/cm2 at 550 and 600°C, respectively), with an OCV of 1.04 V at 600°C, indicating that the PLD technique was successful in depositing a sufficiently dense ScSZ electronic blocking layer to suppress electronic conduction normally observed across single-layer SDC electrolytes, and which typically result in lower OCV values (0.87 V, 600°C) [46, 127],... 

In this chapter, we reviewed the structure-controlled syntheses of CNFs in an attempt to offer better catalyst supports for fuel cell applications. Also, selected carbon nanofibers are used as supports for anode metal catalysts in DMFCs. The catalytic activity and the efficiency of transferring protons to ion-exchange membranes have been examined in half cells and single cells. The effects of the fiber diameter, graphene alignment and porosity on the activity of the CNF-supported catalysts have been examined in detail. 

In the present chapter, the mathematical model defined in Chapter 3 is applied for two particular geometries, namely an anode-supported disk-shaped single cell and an anode-supported micro-tubular single cell. 

The micro-tubular SOFCs considered are depicted in Figure 4.19. Specifically, Figure 4.19 shows the anode (supporting structure), the anode plus the electrolyte, and the final single cells. More details about the production process, the cell properties and characteristics can be found in [13-15],... 

Table 5.1 Physical dimensions of single fuel cell with anode supported electrolyte.

Shao, Z., Kwak, C., and Haile, S. M. Anode-Supported Thin-film Fuel Cells Operated in a Single Chamber Configuration, Solid State Ionics, 175, 39 (2004). 

Single-cell tests - anode-supported cells... 

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