Molten carbonate fuel cells development

Molten Carbonate Fuel Cell developed by Baur (1921)... 

From the very outset of molten carbonate fuel cell development, research workers were attracted by the fact that not only hydrogen but also carbon monoxide could be used as a reactant fuel (reducing agent). Carbon monoxide (the so-called water gas, a mixture of CO and H2) is readily obtained by the steam gasification of coal ... 

Ghezell-Ayagh et al. (1999) Development of a stack simulatioin model for control study on direct reforming molten carbonate fuel cell power plant, IEEE Trans. Energy Conversion, Vol. 14, No. 4. 

In applications for static purpose, phosphoric add fuel cells have been constructed on a large scale for mainly test purposes. They have shown commerdal level performance and stability. More advanced types of fuel cells like molten carbonate fuel cells and solid oxide fuel cells are also under development for this purpose but are %t to reach that level. 

FCE s German partner, MTU Friedrichshafen, is operating a 250 kilowatt molten carbonate fuel cell system in Bielefeld, Germany. The power plant is located on the campus of the University of Bielefeld and provides electric power and byproduct heat. The fuel cells were manufactured by FCE. MTU developed a new power plant configuration for this unit termed a Hot Module that simplifies the balance of plant. The system began operation in November 1999 and logged over 4,200 hours by August, 2000. Electric efficiency is 45% (LHV). 

Development of Improved Molten Carbonate Fuel Cell Technology," Final Report prepared by United Technologies Corp. for the Electric Power Research Institute, Palo Alto, CA, under Contract RP 1085-4, July 1983. 

K. Hoshino, T. Kohno, Central Research Institute, Mitsubishi Material Co., "Development of Copper Base Anodes for Molten Carbonate Fuel Cells," in The International Fuel Cell Conference Proceedings, NEDO/MITI, Tokyo, Japan, Pgs. I69-I72, 1992. 

T. Tanaka, et al., "Development of Internal Reforming Molten Carbonate Fuel Cell Technology," in Proceedings of the 25th lECEC, American Institute of Chemical Engineers, New York, NY, August 1990. 

Molten carbonate fuel cells (MCFCs) are currently being developed for natural gas and coal-based power plants for electrical utility, industrial, and military applications. MCFCs are high-temperature fuel cells that use an electrolyte composed of a molten carbonate salt mixture suspended in a porous, chemically inert ceramic lithium aluminium oxide (LiAI02) matrix. Since they operate at extremely high temperatures of 650°C and above, non-precious metals can be used as catalysts at the anode and cathode, reducing costs. 

Selman J. R., Research, Development and Demonstration of Molten Carbonate Fuel Cell Systems in Fuel Cell Systems, Leo Blomen, M. N. Mugerwa, eds, Plenum Press, New York, 1993, p. 345. 

Other fuels were also tried in the early stages of fuel cell development. Coal, the major fuel at that time, was considered as a candidate. Attempts to replace hydrogen with coal resulted in the invention of alkaline fuel cells (AFCs) and molten carbonate fuel cells (MCFCs). Mond used reformate gas from coal, which contained abundant hydrogen, as the fuel, with the intention of scaling up Grove s fuel cell to produce electric power. However, impurities poisoned the catalyst and made Mond s design impractical. 

Molten carbonate fuel cell technology was developed based on the work of Bauers and Ehrenberg, Davy tan, and Broers and Ketelaar in the 1940s [8], The electrolyte is a molten salt such as sodium carbonate, borax, or cryolite. This type of fuel cell requires a high temperature to keep the electrolyte in a molten state. The following 30-40 years saw great successes, with the development of MCFCs and MCFC stacks that could be operated for over 5000 hours. 

Several types of fuel cells have been developed and are classified according to the electrolytes used alkaline fuel cells, molten carbonate fuel cells, phosphoric acid fuel cells (PAFCs), PEMFCs, and solid oxide fuel cells (SOFCs). As shown in Figure 1.3, the optimum operation temperatures of these fuel cells are different, and each type has different advantages and disadvantages. 

In recent decades, research has intensified to develop commercially viable fuel cells as a cleaner, more efficient source of energy, due to the global shortage of fossil fuels. The challenge is to achieve a cell lifetime suitable for transportation and stationary applications. Among the possible fuel cell types, it is generally believed that PEM fuel cells hold the most promise for these uses [10, 11], In order to improve fuel cell performance and lifetime, a suitable technique is needed to examine PEM fuel cell operation. EIS has also proven to be a powerful technique for studying the fundamental components and processes in fuel cells [12], and is now widely applied to the study of PEM fuel cells as well as direct methanol fuel cells (DMFCs), solid oxide fuel cell (SOFCs), and molten carbonate fuel cells (MCFCs). 

Batra, V., Maudgal, S., Bali, S., Tewari, P. (2002). Development of aplha lithium alu-minate matrix for molten carbonate fuel cell. /. Power Sources 112, 322-325. 

Lusardi, M., Bosio, B., Arato, E. (2004). An example of innovative application in fuel cell system development COj segregation using molten carbonate fuel cell. /. 

However, at the present fuel cells, for example PAFC (Phosforic acid fuel cell) or MCFC (Molten carbonate fuel cell), the residual fuel is finally burned by the already N2-diluted e2(hausted gas for the heat supply in order to convert the fuel to hydrogen and CO. On the other hand, SOFC (Solid oxide fuel cell) could more easily separate the CO2 recycling gas Much more research and development should be necessary for the recovery of CO2 in the fuel cell system. 

Similar efforts in solid-state electrochemistry for SOFC development focus on the exploration of new perovskites not only for the ORR but also for the anodic oxidation of hydrocarbons [182]. In this area, the discovery that Cu-based anodes present a viable alternative to the classical Ni-YSZ cermet anodes is particularly noteworthy [166, 183, 184], owing to the significant enhancement of performance by avoiding coke deposition. Similar important advances have occurred in the molten carbonate fuel cell (MCFC) area [9]. 

Molten Carbonate Fuel Cells (MCFCs) The development of molten carbonate fuel cells (MCFCs) started in 1951, when Boers and Ketlaar built a fuel cell with a mixture of sodium carbonate and tungsten oxide as electrolyte later they changed it to a mixture of lithium,... 

General Electric Company. Development of Molten Carbonate Fuel Cell Power Plant, Final Report for U.S. DOE/Contr. DE-A02 80ET/7019, 1985. 

Pigeaud, A. Maru, H.C. Paetsch, L. Doyon, J. Bernard, R. Recent developments in porous electrodes for molten carbonate fuel cells. Proceedings of the Symposium on Porous Electrodes Theory and Practices, Maru, H.C., Katan, T., Klein, M.G., Eds. The Electrochemical Society, Inc. Pennington, NJ, 1984 234-259. 

General Electric Co. Development of Molten Carbonate Fuel Cells for Power Generation, Report No. SRD 80-053 General Electric Co. Apr 1980. 

Pierce, R.D. Smith, J.L. Poeppel, R.B. A review of cathode development for molten carbonate fuel cells. In Molten Carbonate Fuel Cell Technology, Proceedings Electrochemical Society, 1984 Vol. 84-13, 147-174. 

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