An alkaline direct ethanol fuel cell with a cation exchange membrane liang an and t. Jan 01, 2008 ive seen a lot of fuel cells that run on methanol, but the igen data sheet pdf was the first time ive seen a company make specific promises about both power output and fuel consumption. Ethanol as fuel for fuel cells comparison methanol and ethanol methanol ethanol physical properties energy density mjkg 19,7 30,0 boiling point c 64,7 78,0 vapour pressure at 20c mbar 129 58 other properties permitted form of distribution packaged only bulk availability special supply chain super market. The major benefit to this type of fuel cell is that an ethanol supply chain is already available and there are a number of sources from which ethanol can be generated. In this paper, its aimed to pre sent a 2d analytical model for direct ethanol fuel cell defc performance. A dualcell passive direct ethanol fuel cell defc stack with single ethanol tank was designed and tested to obtain the voltage requirement of electronics and to reduce weight and volume for.
Direct ethanol fuel cells have attracted much attention recently. Origin of low co2 selectivity on platinum in the direct. This paper assesses the beha viour of a direct methanol fuel cell fed with aqueous methanol, aqueous ethanol and aqueous methanolethanol blends in a long term. Environmental 46 2003 273285 pt based anode catalysts for direct ethanol fuel cells weijiang zhoua, zhenhua zhoua, shuqin songa, wenzhen lia, gongquan suna, panagiotis tsiakarasb, qin xina,c. By comparison, ethanol is more environmentally friendly and can be easily produced in large quantities from agricultural products or biomass. Catalysts for alcoholfuelled direct oxidation fuel cells. This paper assesses the beha viour of a direct methanol fuel cell fed with aqueous methanol, aqueous ethanol and aqueous methanol ethanol blends in a long term. The most attractive direct ethanol fuel cell defc technology for vehicle applications is based on alkaline, aaem, enabling the usage ofmembranes ptfree catalysts. Electrochemical characterization of lowtemperature direct. Direct ethanol pemfuel cells performance on binary catalysts direct ethanol fuel cell operation over different bimetallic anode catalysts at 90 c.
Jun 14, 2016 the greater range comes from the more efficient process of reforming ethanol into hydrogen and using that in a fuel cell to produce electricity, which generates more energy to turn the wheels than. The use of alcohol blends in direct alcohol fuel cells may be a more environmentally friendly and less toxic alternative to the use of methanol alone in direct methanol fuel cells. Defc uses ethanol in the fuel cell instead of the more toxic methanol. Protonexchangemembranebased direct ethanol fuel cell single cell tests with online ms analytics of the anolyte for single cells with a ptsnc anode with 3. Direct methanol fuel cells dmfcs, however, are powered by pure methanol, which is usually mixed with water and fed directly to the fuel cell anode. Direct ethanol fuel cells with superior ethanoltolerant. The performance of three alkaline direct ethanol fuel cells adefcs is investigated. Hards johnson matthey technology centre the direct methanol fuel cell dmfc has been considered as the ideal fuel cell system since it produces electric power by the direct conversion of the methanol fuel at the fuel cell anode. Zhao received 4th january 2011, accepted 30th march 2011 doi.
Oct 12, 2006 a direct ethanol fuel cell offers an attractive, fairly high density, energy source, if an electrochemical system can be developed that efficiently carries out the 12electron oxidation of ethanol to carbon dioxide and water. Principles of direct methanol fuel cells for portable and. Direct ethanol fuel cells defcs, which use ethanol as a fuel, have attracted considerable attention due to their relatively high energy density, the nontoxicity of ethanol, and the abundance of ethanol sources. To evaluate the effect of the membrane thickness on the that permeates from the anode. First, it has a lower density than any other fuel compare liquid hydrogens 70. This has lead to a considerable interest in developing fuel cell systems operating directly on bioethanol. Direct methanol fuel cells technological advances and further requirements by m. Directmethanol fuel cell their main advantage is the ease of transport of methanol, an energydense yet reasonably stable liquid at all environmental conditions. Direct ethanol fuel cell acetaldehyde acetic acid ptsno 2c electrocatalysts abstract ptsno 2c with pt. Acetaldehyde, acetic acid and mixtures of them with ethanol were also tested as. The direct ethanol fuel cell that we proposed herein uses natural clay as the electrolyte. Characterization and analysis of new catalysts for a.
However, since the crossover of ethanol as a fuel in defcs can deteriorate the cell performance due to the oxidation of ethanol etoh at the cathode during oxygen reduction reaction. The greater range comes from the more efficient process of reforming ethanol into hydrogen and using that in a fuel cell to produce electricity, which generates more energy to turn the wheels than. Direct alcohol fuel cells for portable applications. Ethanol is the most used bio fuel worldwide with an existing supply chain and infrastructure in many parts around the world. A selective electrocatalystbased direct methanol fuel cell operated at high concentrations. Pdf performance of a passive direct ethanol fuel cell. Pdf direct ethanol fuel cells defcs are a promising carbonneutral and sustainable power source for portable, mobile, and stationary applications find. Direct ethanol fuel cell using hydrotalcite clay as a. The results showed that fuel cells have a high performance at. The sufficient feeding of aqueous ethanol solution into direct ethanol fuel cell stack exhibited very high voltage and high current level of 1. What are the advantages of direct methanol fuel cells. Experimental investigation of a passive direct ethanol fuel cell defc is presented in this work.
An aqueous methanol solution of low molarity acts as the reducing agent that traverses the anode flow field. Direct ethanol fuel cells for transport and stationary applications a. Oliveira et al performance evaluation of a platinumfree microscale alkaline direct ethanol fuel cell operating for long periods hamish a. Direct ethanol fuel cells defcs, which use ethanol as a fuel, have. However, conventional defcs that use acid protonexchange membranes typically nafion type and platinumbased catalysts exhibit low performance i. Ethanol is the most used biofuel worldwide with an existing supply chain and infrastructure in many parts around the world. An alkaline direct ethanol fuel cell with a cation. Pt based anode catalysts for direct ethanol fuel cells. A direct methanol fuel cell dmfc is an electrochemical cell that generates electricity based on the oxidation of methanol and reduction of oxygen. Special attentions are given to direct ethanol fuel cells defcs and direct methanol fuel cells dmfcs. A direct ethanol fuel cell offers an attractive, fairly high density, energy source, if an electrochemical system can be developed that efficiently carries out the 12electron oxidation of ethanol to carbon dioxide and water. Analytical models provide useful information for researchers to study fuel cell function. Introduction direct ethanol fuel cell is an electrochemical device which converts the energy through chemical reactions. The model included equations inside diffu sion layer, catalyst layer, and ethanol crossover through membrane, which all have been solved.
Direct methanol fuel cell their main advantage is the ease of transport of methanol, an energydense yet reasonably stable liquid at all environmental conditions. However, the presence of a large amount of water on the effect of the ethanol feed concentration on fuel cell perfor the cathode due to the oxygen reduction reaction along with water mance. An alkaline direct ethanol fuel cell with a cation exchange. In alkaline fuel cells of this type, the metal cations react with dissolved co 2 in alcohol fuels producing metal carbonate precipitates that decrease the fuel cell performance. This is more attractive than the conventional hydro gen fuelled cells. Miller et althis content was downloaded from ip address 207.
Also the high efficiency makes defc attractive, but the absence of cells and prototypes tested and evaluated in terms of vehicle demands makes the technology more challenging. The energy produced from a direct ethanol fuel cell defc is theoretically higher than the pioneer direct methanol fuel cell dmfc. Long term performance study of a direct methanol fuel cell. To that end, new catalyst systems must be developed along with fuel cell operating conditions that encourage the complete oxidation of ethanol, as opposed to the. Energy conversion using pdbased catalysts in direct ethanol. Study on the performance of the micro direct ethanol fuel cell. They have been used as a model to investigate a range of fuel cell concepts including the use of pem. Feb, 2012 the direct ethanol fuel cell defc represents one of the most exciting future clean energy solutions in modern research, because ethanol can be sustainably produced from biomass, is relatively nontoxic and, most importantly, has a high energy density. The practical efficiencies of fuel cells with ethanol as the anode fuel are still low in comparison with other investigated fuels, such as hydrogen. Fundamentals, engineering and advances presents the fundamental concepts, technological advances and challenges in developing, modeling and deploying fuel cells and fuel cell systems for portable devices, including micro and mini fuel cells. Pdf an alkaline direct ethanol fuel cell with a cation. Comparison of alkaline direct ethanol fuel cells with and without.
Dec 20, 2017 hydrogen is very difficult to deal with. Two important features can be obtained with the use of this membrane. In direct alcohol fuel cells dafcs, alcohol is directly oxidised at the anode in an acidic. All three use identical anode and cathode electrodes, but one uses an. Pdf anionexchange membrane direct ethanol fuel cells. Pdf a micro alkaline direct ethanol fuel cell with. Fuel cells are divided into two types of alcohol fuel cell that are direct methanol fuel cell dmfc and ethanol fuel cell defc. Efficiency is quite low for these cells, reaching around 10% 1, so they are targeted especially to portable applications, where energy and power density are more important than. This is an important subject and the authors general description can easily be followed by students in chemistry or related subjects. However, since the crossover of ethanol as a fuel in defcs can deteriorate the cell performance due to the oxidation of ethanol etoh at the cathode during oxygen reduction. At 75 c, the single ethanol fuel cell with pt3sn2c as anode catalyst showed a comparable performance to that with pt2sn1c, but at higher temperature of 90 c, the latter presented much better performance.
Ive seen a lot of fuel cells that run on methanol, but the igen data sheet pdf was the first time ive seen a company make specific promises about. Direct ethanol fuel cells defcs are attractive as a power source options because ethanol is a nontoxic, leading to ease of handling and a high energy density fuel, leading to high system energy density. Chapter 6 deals with the description of different membranes used in direct alcohol fuel. In the anode side a mixture of ethanol and naoh aqueous solution is inserted as fuel, in the cathode, the inlet of humidified oxygen closes the system. Portable fuel cells powered directly by ethanol could soon be practical, thanks to a new catalyst that breaks a strong bond at the heart of ethanol molecules, freeing electrons and generating. In direct alcohol fuel cells dafcs, alcohol is directly oxidised at. The effect of acetaldehyde and acetic acid on the direct.
Experimental investigation of a passive direct ethanol fuel cell. Performance of alkaline electrolytemembranebased direct. Direct ethanol fuel cells or defcs are a category of fuel cell in which ethanol is fed directly into the cell. Box 110, dalian 116023, pr china b department of mechanical. The direct ethanol fuel cell performance scientific.
Additional electrochemical data, tem images, and xps spectra pdf. Direct methanol fuel cell dmfc performanceworcester polytechnic institute. Direct ethanol fuel cells are able to burn ethanol without first reforming it to hydrogen. A micro alkaline direct ethanol fuel cell with platinumfree catalysts. Pdf direct ethanol fuel cells defcs are attractive as a power source options because ethanol is a nontoxic, leading to ease of handling and. A micro alkaline direct ethanol fuel cell with platinum. Also, the oxygen reduction reaction orr is considered in both of them. Hence, direct ethanol fuel cells defcs have recently received. This fuel cell does not use any auxiliary devices such as pumps, gas compressors, and gas blowers.
The direct ethanol fuel cell defc represents one of the most exciting future clean energy solutions in modern research, because ethanol can be sustainably produced from biomass, is relatively nontoxic and, most importantly, has a high energy density. However, to provide practical defcs power source there are several issues that still must be addressed. The direct methanol fuel cell dmfc enables the direct conversion of the chemical energy stored in liquid methanol fuel to electrical energy, with water and carbon dioxide as byproducts. This power density is about four times higher than any other sofc. Characterization and analysis of new catalysts for a direct. The voltage drop of the direct ethanol fuel cell was observed with increasing current in fig 5. Direct ethanol fuel cells defcs are a promising carbonneutral and sustainable power source for portable, mobile, and stationary applications.
Pdf a micro alkaline direct ethanol fuel cell with platinum. The demand for energy, coupled with concerns about. Ethanol electrooxidation, pd catalyst, alkaline media 1. A dual cell passive direct ethanol fuel cell defc stack with single ethanol tank was designed and tested to obtain the voltage requirement of electronics and to reduce weight and volume for. To that end, new catalyst systems must be developed along with fuel cell operating conditions that encourage the complete oxidation of ethanol, as. The recent developments of platinum and nonplatinumbased catalysts as methanol and ethanol tolerant oxygen reduction catalysts for direct alcohol fuel cells are described in chap. Direct alcohol fuel cells dafcs have attracted enormous attention as powerful sources for portable electronic devices and transportation due to the much higher energy density than gaseous fuels such as hydrogen and natural gas. Electrooxidation of ethanol on pt in the absence of water. Direct alcohol fuel cells for portable applications 1st edition. Ethanol 27, 2propanol 8,9, ethylene glycol 10 and glycerol 14 have all been considered for fuel cell applications. Energy conversion using pdbased catalysts in direct. Direct alcohol fuel cells for portable applications 1st. Direct methanol fuel cells do not have many of the fuel storage problems typical of some fuel cell systems because methanol has a higher energy density than hydrogenthough less than gasoline or. Fuel cells are of tremendous interest, from both energy and environmental considerations.
The direct methanol fuel cell dmfc has been considered as the ideal fuel cell system since it produces electric power by the direct conversion of the methanol fuel at the fuel cell anode. The operation principle of an anion exchange membrane direct ethanol fuel cell aemdefc is illustrated in figure 15. The authors highlight that the theoretical effi ciencies for methanolair and ethanolair fuel cells are actually higher than. Direct ethanol proton exchange membranes fuel cells depemfc. A passive direct formate fuel cell using ambient air is designed, fabricated, and tested. Pdf experimental investigation of a passive direct.
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