Alkaline membrane fuel cell

Solid alkaline membrane fuel cells (SAMECs) can be a good alternative to PEMFCs. The activation of the oxidation of alcohols and reduction of oxygen occurring in fuel cells is easier in alkaline media than in acid media [Wang et al., 2003 Yang, 2004]. Therefore, less Pt or even non-noble metals can be used owing to the improved electrode kinetics. Eor example, Ag/C catalytic powder can be used as an efficient cathode material [Demarconnay et al., 2004 Lamy et al., 2006]. It has also... 

Lamy C, Demarconnay L, Coutanceau C, Leger JM. 2006. Development of electrocatalysts for the solid alkaline membrane fuel cell (SAMEC). ECS Trans 3(1) 1351-1360. 

DMFCs and direct ethanol fuel cells (DEFCs) are based on the proton exchange membrane fuel cell (PEM FC), where hydrogen is replaced by the alcohol, so that both the principles of the PEMFC and the direct alcohol fuel cell (DAFC), in which the alcohol reacts directly at the fuel cell anode without any reforming process, will be discussed in this chapter. Then, because of the low operating temperatures of these fuel cells working in an acidic environment (due to the protonic membrane), the activation of the alcohol oxidation by convenient catalysts (usually containing platinum) is still a severe problem, which will be discussed in the context of electrocatalysis. One way to overcome this problem is to use an alkaline membrane (conducting, e.g., by the hydroxyl anion, OH ), in which medium the kinetics of the electrochemical reactions involved are faster than in an acidic medium, and then to develop the solid alkaline membrane fuel cell (SAMFC). 

After rehearsing the working principles and presenting the different kinds of fuel cells, the proton exchange membrane fuel cell (PEMFC), which can operate from ambient temperature to 70-80 °C, and the direct ethanol fuel cell (DEFC), which has to work at higher temperatures (up to 120-150 °C) to improve its electric performance, will be particularly discussed. Finally, the solid alkaline membrane fuel cell (SAMFC) will be presented in more detail, including the electrochemical reactions involved. 

SOFC = solid oxide fuel cell MCFC = molten carbonate fuel cell PAFC = phosphoric acid fuel cell AFC = alkaline fuel cell PEMFC = proton exchange membrane fuel cell DMFC = direct methanol fuel cell SAMFC = Solid alkaline membrane fuel cell. 

Solid alkaline membrane fuel cell (SAMFC) working at moderate temperatures (20-80 °C) for which an anion-exchange membrane (AEM) is the electrolyte, electrically conducting by, for example, hydroxyl ions (OH ). 

Solid Alkaline Membrane Fuel Cell (SAMFQ 29... 

A second class of fuel cells employs hydroxide-conducting (alkaline) electrolytes, again either in form of a solid membrane (alkaline membrane fuel cells) or a liquid electrolyte (alkaline fuel cells). While the modem era of fuel cells began with the latter type, the former type is under intense research today because a stable, highly conducting alkaline membrane with good C02 tolerance has remained elusive to date. 

Alkaline membrane fuel cell Solid polymer OH" 50°C-100°C Pure H2, liquid small organics (limited C02 tolerance) <35% Portable, under research... 

Hie A, Simoes M, Baranton S, Coutanceau C, Martemianov S (2011) Influence of operational parameters and of catalytic materials on electrical performance of direct glycerol solid alkaline membrane fuel cells. J Power Sources 196 4965-4971... 

Simoes M (2011) Development of multimetallic nanostructured electrocatalysts for an application in a solid alkaline membrane fuel cell (SAMFC). Thesis, Universite de Poitiers, Poitiers... 

Zhou J, Unlii M, Anestis-Richard I, Kohl PA (2010) Crosslinked, epoxy-based anion conductive membranes for alkaline membrane fuel cells. J Membr Sci 350 286-292... 

Scott K, Yu EH, Vlachogiannopoulos G, Shivare M, Duteanu N (2008) Performance of a direct methanol alkaline membrane fuel cell. J Power Source 175 452-457... 

Tamain C, Poynton SD, Slade RCT, Carroll B, Varcoe JR (2007) Development of cathode architectures customized for H2/O2 metal-cation-free alkaline membrane fuel cells. J Phys ChemC 111(49) 18423-18430... 

Piana M, Boccia M, Filpi A, Flammia E, Miller HA, Orsini M, Salusti F, Santiccioli S, Ciardelli F, Pucci A (2010) H2/air alkaline membrane fuel cell performance and durability, using novel ionomer and non-platinum group metal cathode catalyst. J Power Sources 195(18) 5875-5881... 

Varcoe JR, Slade RCT, Wright GL, Chen Y (2006) Steady-state dc and impedance investigations of H2/O2 alkaline membrane fuel cells with commercial Pt/C, Ag/C, and Au/C cathodes. J Phys Chem B 110(42) 21041-21049... 

Qiao J, et al. (2013) Carbon-supported co-pyridine as non-platinum cathode catalyst for alkaline membrane fuel cells. Electrochim Acta 96 298-305. doi 10.1016/j. electacta.2013.02.030... 

This chapter reviews a new type of solid electrolyte low-temperature fuel cell, the alkaline membrane fuel cell. The principles and main components of this fuel cell technology are described, with a major focus on the electrocatalysts for both electrodes. Finally, the latest published results on operation of the first developed alkaline membrane fuel cells are reviewed. 

Alkaline Membrane Fuel Cells, Fig. 1 Schematic diagrams of a proton exchange membrane fuel cell, PEMFC left), and an alkaline membrane fuel cell, AMFC (right)... 

In the following sections, a general review of the state of the art in alkaline membrane fuel cell technology is presented, and anion exchange membranes and electrocatalysts for this new technology are described. In addition, a short review of today s alkaline membrane fuel cell performance is also presented. 

Due to the ample potential of fuel cell commercialization using non-platinum alkaline membrane fuel cells, studies on anion exchange membranes for this technology are now an emerging field both in terms of research and development. 

As it has been pointed out in past years [1], the most critical concerns of the alkaline membrane fuel cell technology were the low conductivity and the poor stability of the early anion exchange membranes. In past years, significant advances were achieved [3, 4], promoting the development of the alkaline membrane fuel cell technology. 

Electrocatalysts for Hydrogen-Air Alkaline Membrane Fuel Cells... 

The oxygen reduction reaction overpotential loss in alkaline membrane fuel cells is very similar to that in proton exchange membrane fuel cells, i.e., the cathode overpotential loss remains an important factor limiting the efficiency and performance of alkaline membrane fuel cells [6, 7]. However, switching to an alkaline medium as in alkaline membrane fuel cells allows for the use of... 

Many publications can be found in the literature on the preparation and testing of non-Pt and non-PGM catalysts [8-10] however, most of the research has been focused on acidic medium for proton exchange membrane fuel cells. There are limited data on catalyst evaluation in alkaline medium [11-14] and even less on catalyst evaluation in real alkaline membrane fuel cells. 

In summary, little work has been done in past years to better understand electrocatalysts in alkaline medium and to develop new effective catalysts for this new and promising alkaline membrane fuel cell technology. Moreover, almost no work has been done in real alkaline membrane fuel cells with catalysts other than platinum. The development of non-Pt and non-Pt group metal (non-PGM) catalysts toward oxygen reduction reaction for alkaline membrane fuel cells now requires further research in order to make this a real affordable technology. 

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