Membrane assembly durability

Endoh, E. and S. Hommura. 2009. Improvement of membrane and membrane electrode assembly durability. In Polymer Electrolyte Fuel Cell Durability, eds. F.N. Buchi, M. Inaba, and T.J. Schmidt, New York, NY Springer, pp. 119-132. 

Improvement of Membrane and Membrane Electrode Assembly Durability... 

Xie J, Wood DL, More KL, Atanassov P, Borup RL. 2005a. Microstructural changes of membrane electrode assemblies during PEFC durability testing at high humidity conditions. J Electrochem Soc 152 A1011-A1020. 

Yi, J. et al.. Development of a low cost, durable membrane and membrane electrode assembly for fuel cell applications, in Extended Abstracts of 2006 Fuel Cell Seminar, Honolulu, HI, November 13-18, 2006, p. 261. 

The tube-and-shell, or tubular, membrane module is easily adapted for use with drawn tubular membranes as well as membranes that are made by depositing a thin permselective metal layer onto a porous tube support. There are three significant variants to this module design. One is based on the membrane tubes fixed to a header at each end of the membrane tube. The second is similar in that both ends of the membrane tubes are fixed to a header, but to the same header. In the second design, the membrane tubes are bent into a U shape, which can be easily done with small diameter metal tubes. The third is based on a single header, to which open sides of closed-one-ended membrane tubes are fixed. The closed-ends of the membrane tubes are suspended freely. This latter design is more common for commercial applications, due to free thermal expansion and greater membrane durability (see above discussion), whereas laboratory test-and-evaluation practices favor the first variant for its ease of assembly. If the membrane is a drawn, thin-walled tube, the membrane tube will usually be brazed to the header. This is more difficult if the membrane tubes are to be fixed at both ends to head-... 

J. Xie, D. L. Wood III, K. L. More, P. Atanassov, and R. L. Borup, Micro-structural Changes of Membrane Electrode Assemblies During PEFC Durability Testing at High Humidity Conditions, /. Electrochem. Soc., 12, AlOl 1 (2005). 

Mechanical integrity is one of the most important prerequisites for fuel cell membranes in terms of handhng and fabrication of membrane electrode assemblies, and to offer a durable material. Robust fuel cell membranes are required because of the presence of mechanical and swelling stresses in the application [172]. Moreover, membranes should possess some degree of elasticity or elongation to prevent crack formation. 

Alcohol crossover and cell resistance are the relevant properties determining the DAFC performance, which are closely related to the membrane used in the preparation of the membrane-electrode assembly (MEA). Mechanical properties, as well as the chemical and thermal stability, of the membrane could also be important when durability is considered. 

A membrane electrode assembly (MEA), where the fuel cell anode and cathode halfreactions occur, is the heart and the most delicate part of a fuel cell system. The performance, stability, and durability of a fuel cell largely depend on the quality of the MEAs. Therefore, MEA qualification should be critical in developing durable, high performanee fuel eell systems. 

PDMAEMA brushes were also prepared on the surface of the nanopores in freestanding silica colloidal membranes [61], which showed similar pH-responsive transport behavior [62]. The free-standing silica colloidal membranes were prepared from silica spheres that were calcinated for 4 h at 600 °C, and were then assembled into colloidal crystals by vertical deposition using 12 wt% colloidal solutions in ethanol. The colloidal films were sintered at 1050 °C for 12 h to produce durable free-standing membranes (Fig. 8.16), followed by rehydroxylation with tetrabutyl-ammonium hydroxide in water to restore the surface hydroxyl groups. 

The development of commercially viable proton exchange membrane (PEM) fuel cell systems powered by hydrogen or hydrogen-rich reformate faces a significant number of materials and MEA (membrane electrode assembly) design-related performance and durability challenges, which need to be addressed via ... 

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