Internal combustion engines PEMFC

Proton exchange membrane fuel cells (PEMFC) are believed to be the best type of fuel cell as the vehicular power source to eventually replace the gasoline and diesel internal combustion engines. PEMFCs are currently being developed and demonstrated for systems ranging from 1W to 2 kW. 

The efficiency of PEMFCs ranges from about 40 to 50%, and operating temperature is about 255 K. The PEMFCs and direct methanol fuel cells (DMFCs) are considered to be promising power sources, especially for transportation applications. The PEMFCs with potentially much higher efficiencies and almost zero emissions offer an attractive alternative to the internal combustion engines for automotive applications. This fuel cell has many important attributes such as high efficiency, clean, quiet, low-temperature operation, capable of quick start-up, no liquid electrolyte and simple cell design (Hu et al., 2004). 

Hydrogen in the gaseous state has long been investigated as a clean energy source for internal combustion engines and PEMFC. [Note PEMFC is sometimes simply called Polymer Electrolyte Fuel Cell (PEFC)]. 

The fuel cell (EC) presents a clean power source alternative to current internal combustion engines. Among the many types of PCs characterized by their electrolytes, the polymer electrolyte membrane fuel cell (PEMFC) is lightweight and small, has a reasonably facile membrane fabrication, and shows great promise. However, one key weak point that continues to draw attention is the slow dynamic limitation demonstrated by PEMFCs during experimental use and the negative consequences that can result. 

The PEMFC has been under development for the last two decades primarily as a potential replacement for internal combustion engines in electric passenger vehicles with power needs of 50-100 kW. However, PEMFCs have also been considered for larger vehicles of few hundred kilowatts for buses and trucks, as auxiliary power units, for small-scale stationary power generations of few kilowatts for combined heat and power of residential buildings, and even in smaller units of few watts for portable power electronics applications (Li, 2008 O Hayre et al, 2006). 

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