Polymer electrolyte fuel cell operation

As can be seen from Eigure 11b, the output voltage of a fuel cell decreases as the electrical load is increased. The theoretical polarization voltage of 1.23 V/cell (at no load) is not actually realized owing to various losses. Typically, soHd polymer electrolyte fuel cells operate at 0.75 V/cell under peak load conditions or at about a 60% efficiency. The efficiency of a fuel cell is a function of such variables as catalyst material, operating temperature, reactant pressure, and current density. At low current densities efficiencies as high as 75% are achievable. 

L. R. Jordan, A. K. Shukla, T. Behrsing, et al. Effects of diffusion-layer morphology on the performance of polymer electrolyte fuel cells operating at atmospheric pressure. Journal of Applied Electrochemistry 30 (2000) 641-646. 

Springer, T.E. et al.. Model for polymer electrolyte fuel cell operation on reformate feed effects of CO, H2 dilution, and high fuel utilization, J. Electrochem. Soc., 148, All, 2001. 

The main problem in elevated-temperature-polymer electrolyte fuel cell operation is degradation of the membrane at the higher temperature. Marked water loss raises the ohmic resistance of the membrane, causes brittleness, and may give rise to crack formation. For this reason, most polymer electrolyte fuel cells research at present addresses the question of how to maintain the membrane in good working condition in an elevated-temperature-polymer electrolyte fuel cell. 

Kim HJ, Krishnan NN, Lee SY, Hwang SY, Kim D, Jeong KJ, et al. Sulfonated poly(ether sulfone) for universal polymer electrolyte fuel cell operations. J Power Source 2006 160(l) 353-8. 

The aforementioned polymeric electrolytes have been effectively used in polymer electrolyte fuel cells operating up to In order to study the single cell performance and apart from the high ionic conductivity of the membrane, several parameters residing the MEA constmction must be taken into account in order to have optimum performance of the cell. Some of these parameters are the amount of the catalyst the ionomer-binder used at the electrodes and its percentage, electrode surface and the preparation method, pressure and the temperature of the MEA assembling and design and constmction parameters of the cell. ... 

Du, B., Pollard, R., Elter, J.F., and Ramani, M. (2009) Performance and durability of a polymer electrolyte fuel cell operating with reformate ... 

Li Q, He R, Gao J-A, Jensen JO, Bjerrum NJ (2003) The CO poisoning effect in polymer electrolyte fuel cells operational at temperatures up to 200°C. J Electrochem Soc 150 A1599-A1605... 

Kabasawa A, Saito J, Yano H, Miyatake K, Uchida H et al. (2009) Durability of a novel sulfonated polyimide membrane in polymer electrolyte fuel cell operation . Electrvchimica Acta 54 1086. 

Bhatia, K. K. and Wang, C.-Y. 2004. Transient carbon monoxide poisoning of a polymer electrolyte fuel cell operating on diluted hydrogen feed. Electrochimica Acta 49 2333-2341. 

Performance and Durability of a Polymer Electrolyte Fuel Cell Operating with Reformate Effects of CO, CO2, and Other Trace Impurities... 

Bhatia, K. K. and Wang, C.-Y. (2004). Transient carbon monoxide poisoning of a polymer electrolyte fuel cell operating on diluted hydrogen feed. Electrochim. Acta 49(14) 2333-2341 Bird, R. B., Stewart, W. E., and Lightfoot, E. N. (1960). Transport Phenomena. New York, Wiley... 

Aoki, M., Asano, N., Miyatake, K., Uchida, H., Watanabe, M. (2006) DurabiUty of sulfonated polyimide membrane evaluated by long-term polymer electrolyte fuel cell operation. Journal of the Electrochemical Society, 153, A1154—A1158. 

T. E. Springer, T. Rockward, T.A. Zawodzinski, and S. Gottesfeld, Model for Polymer Electrolyte Fuel Cell Operation on Reformate Feed—Effects of CO, H2 Dilution, and High Fuel Utilization, ... 

HBP-SA, HBP-SA-Ac, HBP-PA and HBP-PA-Ac polymers, interpenetrated electrolyte membrane HBP-SA-co-HBP-Ac, and the crosslmked membranes CL-HBP-SA and CL-HBP-PA showed the VTF-type temperature dependence. These polymers and membranes are thermally stable up to 260 °C, and they had suitable thermal stability as an electrolyte in the polymer electrolyte fuel cell operating under non-humidified conditions. Fuel cell measurement using a single membrane electrode assembly cell with crosslinked membranes CL-HBP-SA and CL-HBP-PA was successfully performed under non-humidified conditions, and polarization curves were observed. The concept of the proton conduction coupled with the polymer chain motion was proposed as one possible approach toward high temperature fuel cells. 

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