Polymer electrolyte fuel cell energy conversion

Energy Conversion in Polymer Electrolyte Fuel Cells...344... 

Numerous demonstrations in recent years have shown that the level of performance of present-day polymer electrolyte fuel cells can compete with current energy conversion technologies in power densities and energy efficiencies. However, for large-scale commercialization in automobile and portable applications, the merit function of fuel cell systems—namely, the ratio of power density to cost—must be improved by a factor of 10 or more. Clever engineering and empirical optimization of cells and stacks alone cannot achieve such ambitious performance and cost targets. 

Polymer electrolyte-based fuel cells are emerging as attractive energy conversion systems suitable for use in many industrial applications, starting from a few milliwatts for portables to several kilowatts for stationary and automotive applications. The ability of polymer electrolyte fuel cells to offer high chemical to electrical fuel efficiency and almost zero emissions in comparison to today s prevailing technology based on internal combustion engines (ICEs) makes them an indispensable option as environmental concerns rise [1-6]. 

McElroy, J.F., (General Electric Company), Status of Solid Polymer Electrolyte Fuel Cell Technology, G.E. Direct Energy Conversion Program, Rep. (undated). 

The most important features associated with fuel cell technologies are energy conversion efficiency, durability (or life time), and cost. These are common characteristic features among various fuel cells such as phosphoric acid fuel cells (PAFC), molten carbonate fuel cells (MCFC), polymer electrolyte fuel cells (PEFC), and solid oxide fuel cells (SOFC). For comparison among fuel cells, applications in... 

Wilson M, Derouin C, Valerio J, Gottesfeld S. Electrocatalysis issues in polymer electrolyte fuel cells. Proceedings of the Intersociety Energy Conversion Engineering Conference 1993 1 1203-8. 

Zawodzinski TA, Karuppaiah C, Uribe F, Gottesfeld S. Aspects of CO tolerance in polymer electrolyte fuel cells some experimental findings. In Electrode materials and processes for energy conversion and storage I. Srinivasan S, McBreen J, Khandkar AC, TUak VC, editors. Proceedings of the Electrochemical Society 1997 97(13) 139-146. 

Due to their excellent power density and good energy conversion efficiency, polymer electrolyte firel cells (PEFCs) are promising candidates for transportation, as well as portable and stationary power systems [63]. In recent years, extensive research has been done on the oxygen reduction reaction on platinum at solid polymer electrolyte interfaces [64, 65]. Nafion is often used as the electrolyte in low-temperature fuel cell systems, as it enables the porous catalyzed carbon to be integrated into the electrolyte by extending the three-dimensional reaction zone [66, 67]. 

The Polymer Electrolyte and Direct Methanol Fuel Cells Power Output and Energy-conversion Efficiency... 

---