High power density solid oxide fuel cell

Lu, Y., Schaefer, L. and Li, P. (2005) Numerical study of a flat tube high power density solid oxide fuel cell. Part I Heat/mass transfer and fluid flow, Journal of Power Sources 140, 331-339. 

Virkar A, Wilson L (2003) Low-temperature, anode-supported high power density solid oxide fuel cells with nanostructured electrodes. Technical report. Department of Energy, USA... 

Nehter, R, A high fuel utilizing Solid Oxide Fuel Cell with regard to the formation of nickel oxide and power density, Journal of Power Sources 164, 2007, 252-259. 

Shao, Z., Haile, S. M., Ahn, J., Ronney, P. D., Zhan, Z., and Barnett, S. A. A Thermally Self-Sustained Micro Solid-oxide Fuel-cell Stack with High Power Density, Nature, 435, 795 (2005). 

In many oxidation reactions, the conversion and selectivity from a fuel cell operation tend to compromise each other. At a high selectivity, the conversion is often low and vice versa. Another important issue related to solid oxide fuel cells is that heat from many exothermic partial oxidation reactions docs not provide sufficient energy to justify the process. The resultant power density is usually low. The above two issues can be... 

Z. Shao, S. M. Haile, J. Ahn, P. D. Ronney, Z. Zhan, and S. A. Barnett. A thermally self sustained micro solid oxide fuel cell stack with high power density. Nature 435,... 

Working temperature of solid oxide fuel cells (SOFC) varies in the range of 600-900 °C. A unique feature of these cells is their ability to utilize methane or other hydrocarbons as fuels. In combination with high power density (about 1 W cm ), this makes SOFCs a very attractive power source for residential applications. 

Sasaki H, Otoshi S, Suzuki M, Sogi T, Kajimura A, Sugiura N, Ippommatsu M (1994) Fabrication of high power density tabular type solid oxide fuel cells. Solid Stale Ionics 72 253-256... 

There are various types of fuel cells that are under development. The most noticeable ones are polymer electrolyte membrane (PEM) fuel cells, phosphoric acid fuel cells (PAFC), molten carbonate fuel cells (MCFC), and solid oxide fuel cells (SOFC). PEM fuel cells are mainly being targeted toward transportation needs due to their ability to provide high power densities at reasonable operating temperatures ( 100°C). PAFCs and MCFCs are being developed primarily for stationary applications since their power densities are lower than PEM. SOFCs are currently being developed for both stationary applications and transportation applications but high-temperature material development is needed before they become commercially viable. 

Solid oxide fuel cells offer the potential of high volumetric power density, cost-efficiency, and fuel flexibility, and significant progress has been made during the last 5 years in bringing SOFC technology closer to commercialization. 

In low temperature applications, platinum, which is the most active species of the noble metals, is used as a catalyst. In comparison, high temperature fuel cells such as, for example, the solid oxide fuel cell (SOFC) do not require noble-metal catalysts. The metal loadings usually depend on the kind of application the lowest ones are usually required for automotive applications. At present, total loadings of 0.6-0.8 mgpj/cm (both anodic and cathodic catalysts) are employed the resulting power density is in the range of 0.7 W/cm at a cell voltage of 0.7 V, which amounts to an efficiency of 58%. 

As constructive alternatives, SOFCs can be used as planar or tubular SOFCs, respectively. In the past period, the planar SOFCs become more attractive for the commercialization because of their high power density and low production costs [2]. The planar SOFCs may also be divided into (i) electrolyte-supported and (ii) anode-supported solid oxide fuel cells. Also, more and more attention was focused on solid oxide fuel cells operating at low and/or intermediate temperatures. The decrease of temperature demands an electrolyte with higher ionic conductivity than, for example, the conventional YSZ. 

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