Polymeric membranes fuel cells

Apart of this traditional meaning, recently the term of membrane electrode (assembly) is used. It is defined as two electrodes (the anode and the cathode) with a very thin layer of catalyst, bonded to either side of an ion-exchange membrane. It is an element of polymeric membrane fuel cell. 

Dimethyl ether (DME) is a potential clean fuel and energy source of the next generation since it burns without producing NOx, smoke, or particulates. Steam reforming of DME may be another promising process as the hydrogen source for polymeric membrane fuel cells. 

Membrane-type fuel cells. The electrolyte is a polymeric ion-exchange membrane the working temperatures are 60 to 100°C. Such systems were first used in Gemini spaceships. These fuel cells subsequently saw a rather broad development and are known as (solid) polymer electrolyte or proton-exchange membrane fuel cells (PEMFCs). 

The lonomeric Membrane of the Polymeric Electrolyte Fuel Cell Summary. 270... 

In cases where high purity hydrogen is valued, dense metal membranes are an attractive option over polymeric membranes and porous membranes that exhibit much lower selectivities. Two examples where this is true are low-temperature fuel cells (e.g., proton exchange membrane fuel cells [PEMFCs] and alkaline fuel cells [AFCs]) and hydrogen-generating sites where the product hydrogen is to be compressed and stored for future use. 

In recent years the concept of a fuel cell propulsion system has gained in attention as a result of the need to reduce the fossil fuel consumption and greenhouse gas emissions. Since the fuel cells suitable for vehicle application (polymeric electrolyte membrane fuel cells) are fuelled by hydrogen, and deliver power as long as fuel and air are supplied, they potentially can provide the range capabilities of an internal combustion engine when used in a power system, but with clean and quiet operation. Therefore, the fundamental benefit of this type of propulsion consists in the possibility to adopt pollution-free electric drive-trains, without the drive range limitations typical of traditional electric vehicles. 

Mecham, J.B. (2001) Direct polymerization of snlfonated poly (arylene ether) random copolymers and poly(imide) sulfonated poly(arylene ether) segmented copolymers new candidates for proton exchange membrane fuel cell material systems. Ph.D. Thesis, Virginia Polytechnic Institute and State University. 

The temperature of operation of polymer electrolyte membrane fuel cells tends to get higher, because certain advantages are faced, such as improved tolerance of carbon monoxide, the improved ease of water and heat management, and increased energy efficiency. However, several commonly used polymeric membranes cannot withstand the high temperatures. Therefore, there is a need to look for alternative materials. 

Polymeric functional materials are of central importance for the polymer electrolyte membrane fuel cell (PEMFC) and DMFC technologies in particular. In addition to the expected cost reduction due to low-cost mass productimi, for example of polymeric bipolar plates (see Sect. 2.1), the polymeric membranes are irreplaceable in the PFMFC and DMFC technologies. 

Proton exchange membrane fuel cell or Polymer eleetrolyte membrane fuel cell or Polymer electrolyte fuel eell or Polymeric fuel eell or Polymerie membrane fuel cell or Direct methanol fuel cell or DMFC... 

The membranes in polymeric proton-exchange membrane fuel cells (PEMFC) serve as a solid electrolyte. The membrane s conductivity comes about because in the presence of water it swells, a process leading to the dissociation of the acidic functional groups and formation of protons free to move about throughout the membrane. 

Proton-exchanging membrane fuel cells (PEMFC) are considered to be one of the most promising types of electrochemical device for power generation [1-10]. Low operation temperatures and the wide range of power make them attractive for portable, automotive, and stationary applications. However, advances made in these markets require further cost reduction and improved reliabiUty. These can be achieved through development and implementation of novel proton-exchange membranes with higher performance and lower cost as compared to the state of the art polymeric electrolytes. 

In the Proton-Exchange Membrane Fuel Cell (or Polymer-Electrolyte Membrane Fuel Cell) the electrolyte consists of an acidic polymeric membrane that conducts protons but repels electrons, which have to travel through the outer circuit providing the electric work. A common electrolyte material is Nafion from DuPont , which consists of a fluoro-carbon... 

Carbon nanotubes (CNTs) have been added to a polymeric matrix to improve their mechanical and other properties [69]. The use of CNTs in PEM must be carried out with caution because the well-known high electrical conductivity may cause short circuiting in proton exchange membrane fuel cells. The jt-n interaction between PBI and the side walls of CNT makes these two different materials compatible. Despite CNT-PBI composite membranes have shown enhancement in mechanical strength, the proton conductivity resulted in some cases compromised [70, 71]. Hence, different authors functionalized the CNTS in order to increase both the proton conductivity and the mechanical properties for hydrogen fed PBI-based HT-PEMFC [72, 73]. In this context,... 

Proton exchange membrane fuel cell (PEMFC), schematically shown in Figure 3.7, is using a polymeric proton exchange membrane (PEM) as an electrolyte at temperatures from ambient up to around 120°C. Nafion is used for PEM and Pt for electrodes. Both of these materials are very expensive. The durability of the PEMFC is still under studies for a wide implementation. This fuel cell is considered a first candidate for automotive applications. 

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