Molten carbonate electrolyte membrane

Composite solid oxide/molten carbonate electrolyte membrane... 

Electrolyte Potassium hydroxide Polymer membrane Immobilized liquid molten carbonate Immobilized hquid phosphoric acid Ion exchange membrane Ceramic... 

Electrolyte Ion Exchange Membranes Mobilized or Immobilized Potassium Hydroxide Immobilized Liquid Phosphoric Acid Immobilized Liquid Molten Carbonate Ceramic Ceramic... 

Various types of fuel cells have been developed to generate power according to the applications and load requirements (Chaurasia, 2000). There are several types of electrolyte, which plays a key role in the different types of fuel cells. It must permit only the appropriate ions to pass between the anode and cathode. The main electrolyte types are alkali, molten carbonate, phosphoric acid, proton exchange membrane (PEM), and solid oxide. The first three are liquid electrolytes, the last two are solids. 

Several types of fuel cell are currently under development, using different electrolyte systems phosphoric acid (PAFC), alkaline, molten carbonate (MCFC), regenerative, zinc-air, protonic ceramic, (PCFC), proton exchange membrane (PEM), direct methanol (DMFC), and solid oxide (SOFC). The last four contain solid electrolytes. 

According to the electrolyte and working temperature, one distinguishes the low-temperature fuel cell technologies (i) alkaline fuel cell, AFC (70 to 80°C), (ii) proton exchange membrane fuel cell, PEMFC (70 to 80°C), (iii) phosphoric acid cell, PAFC (200°C) from the high-temperature technologies, (iv) molten carbonate fuel cell, MCFC (650 to 700°C), and (v) solid oxide fuel cell, SOFC (1000°C). 

Note PAFC phosphoric acid fuel cell PEMFC proton exchange membrane fuel cell/polymer electrolyte membrane fuel cell MBFC microbiological fuel cell DMFC direct methanol conversion fuel cell AFC alkaline fuel cell MCFC molten carbonate fuel cell SOFC solid oxide fuel cell ZAFC zinc air fuel cell. 

The most important fuel cells that are in use nowadays are the polymer electrolyte membrane fuel ceU (PEMFC), the molten carbonate fuel cell (MCFC), and the solid oxide fuel cell (SOFC). In a PEMFC, the electrolyte is a polymer membrane that conducts protons, in an MCFC the electrolyte is a carbonate melt in which oxygen is conducted in the form of carbonate ions, CO , and in an SOFC the electrolyte is a solid oxide that conducts oxygen ions, While a PEMFC can be operated at low temperatures of about 80 °C, an MCFC works at intermediate temperatures of about 650 °C, and an SOFC needs relatively high temperatures of 800-1000 °C (see next sections). 

Li, N. Yi, B. Kong, L. Zhang, E. Ling, H. Qu, T. Cheng, Y. Cold-roll-milled electrolyte membrane for molten carbonate fuel cells. Mo Kexue Yu Jishu 1997, 17 (2), 24-29. 

Each of these fuel cells are named or defined by the electrolyte used in them, that is alkaline, phosphoric acid, molten carbonate, solid oxide, proton exchange membrane, etc. 

Fig. 1 Operation principle of the various types of fuel cells PEMFC polymer electrolyte membrane fuel cell, AFC alkatine fuel cell, PAFC phosphoric add fuel cell, MCFC molten carbonate fuel cell, SOFC sohd oxide fuel cell...

Current research is centred on making compact cells of high efficiency. They are described in terms of the electrolyte that is used. The principle types are alkali fuel cells, described above, with aqueous KOH as electrolyte, MCFCs (molten carbonate fuel cells), with a molten alkali metal or alkaline earth carbonate electrolyte, PAFCs (phosphoric acid fuel cells), PEMs (proton exchange membranes), using a solid polymer electrolyte that conducts ions, and SOFCs, (solid oxide fuel cells), with solid electrolytes that allow oxide ion, 0 , transport The... 

The main difference between the two types is in the electrolyte. The MCFC uses a molten carbonate immobilized in a porous LiA102 matrix. The SOFC uses a ceramic membrane of cubic stabilized zirconia. An illustration of the operation of a SOFC is shown in Figure 30.22. 

There exist a variety of fuel cells. For practical reasons, fuel cells are classified by the type of electrolyte employed. The following names and abbreviations are frequently used in publications alkaline fuel cells (AFC), molten carbonate fuel cells (MCFC), phosphoric acid fuel cells (PAFC), solid oxide fuel cells (SOFC), and proton exchange membrane fuel cells (PEMFC). Among different types of fuel cells under development today, the PEMFC, also called polymer electrolyte membrane fuel cells (PEFC), is considered as a potential future power source due to its unique characteristics [1-3]. The PEMFC consists of an anode where hydrogen oxidation takes place, a cathode where oxygen reduction occurs, and an electrolyte membrane that permits the transfer of protons from anode to cathode. PEMFC operates at low temperature that allows rapid start-up. Furthermore, with the absence of corrosive cell constituents, the use of the exotic materials required in other fuel cell types is not required [4]. 

Alkaline FC Polymer Electrolyt Membrane FC Phosphoric Acid FC Molten Carbonate FC Solid Oxide FC ... 

Electrolyte ion exchange membrane potassium hidroxyde phosphoric acid liquid molten carbonate ceramic... 

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