117:
176:(SOFC). PEMFCs operate at a lower temperature, are lighter and more compact, which makes them ideal for applications such as cars. However, some disadvantages are: the ~80 °C operating temperature is too low for cogeneration like in SOFCs, and that the electrolyte for PEMFCs must be water-saturated. However, some fuel-cell cars, including the
446:
195:
The fuel for the PEMFC is hydrogen, and the charge carrier is the hydrogen ion (proton). At the anode, the hydrogen molecule is split into hydrogen ions (protons) and electrons. The hydrogen ions permeate across the electrolyte to the cathode, while the electrons flow through an external circuit and
132:
spaceflight program. A number of technical problems led NASA to forego the use of proton-exchange membrane fuel cells in favor of batteries as a lower capacity but more reliable alternative for Gemini missions 1–4. An improved generation of
General Electric's PEM fuel cell was used in all subsequent
187:
in reformate. These improvements potentially could lead to higher overall system efficiencies. However, these gains have yet to be realized, as the gold-standard perfluorinated sulfonic acid (PFSA) membranes lose function rapidly at 100 °C and above if hydration drops below ~100%, and begin to
265:
As of 2008, the automotive industry as well as personal and public power generation are the largest markets for proton-exchange membrane fuel cells. PEM fuel cells are popular in automotive applications due to their relatively low operating temperature and their ability to start up quickly even in
284:
is a technique by which proton-exchange membranes are used to decompose water into hydrogen and oxygen gas. The proton-exchange membrane allows for the separation of produced hydrogen from oxygen, allowing either product to be exploited as needed. This process has been used variously to generate
832:
Jiangshui Luo; Annemette H. Jensen; Neil R. Brooks; Jeroen
Sniekers; Martin Knipper; David Aili; Qingfeng Li; Bram Vanroy; Michael Wübbenhorst; Feng Yan; Luc Van Meervelt; Zhigang Shao; Jianhua Fang; Zheng-Hong Luo; Dirk E. De Vos; Koen Binnemans; Jan Fransaer (2015).
261:
Early PEM fuel cell applications were focused within the aerospace industry. The then-higher capacity of fuel cells compared to batteries made them ideal as NASA's
Project Gemini began to target longer duration space missions than had previously been attempted.
834:
1205:
257:
The primary application of proton-exchange membranes is in PEM fuel cells. These fuel cells have a wide variety of commercial and military applications including in the aerospace, automotive, and energy industries.
180:, operate without humidifiers, relying on rapid water generation and the high rate of back-diffusion through thin membranes to maintain the hydration of the membrane, as well as the ionomer in the catalyst layers.
196:
produce electric power. Oxygen, usually in the form of air, is supplied to the cathode and combines with the electrons and the hydrogen ions to produce water. The reactions at the electrodes are as follows:
188:
creep in this temperature range, resulting in localized thinning and overall lower system lifetimes. As a result, new anhydrous proton conductors, such as protic organic ionic plastic crystals (POIPCs) and
1175:
903:
183:
High-temperature PEMFCs operate between 100 °C and 200 °C, potentially offering benefits in electrode kinetics and heat management, and better tolerance to fuel impurities, particularly
592:"Barton C. Hacker and James M. Grimwood. On the Shoulders of Titans: A History of Project Gemini. Washington, D. C.: National Aeronautics and Space Administration. 1977. Pp. xx, 625. $ 19.00"
867:
90:, there are many other structural motifs used to make ionomers for proton-exchange membranes. Many use polyaromatic polymers, while others use partially fluorinated polymers.
491:
1227:
278:
based on the technology. The primary challenge facing automotive PEM technology is the safe and efficient storage of hydrogen, currently an area of high research activity.
108:
PEM fuel cells use a solid polymer membrane (a thin plastic film) which is permeable to protons when it is saturated with water, but it does not conduct electrons.
281:
60:
835:"1,2,4-Triazolium perfluorobutanesulfonate as an archetypal pure protic organic ionic plastic crystal electrolyte for all-solid-state fuel cells"
441:, Townsend, Carl W. & Naselow, Arthur B., "Enhanced membrane-electrode interface", issued 2008-11-30, assigned to
1079:
669:
575:
352:
1257:
124:
Early proton-exchange membrane technology was developed in the early 1960s by
Leonard Niedrach and Thomas Grubb, chemists working for the
74:
membranes, where other materials are embedded in a polymer matrix. One of the most common and commercially available PEM materials is the
164:
which allowed only protons to pass through the material, making them a potential replacement for fluorinated ionomers as a PEM material.
1295:
56:
904:"Protic ionic liquid and ionic melts prepared from methanesulfonic acid and 1H-1,2,4-triazole as high temperature PEMFC electrolytes"
902:
Jiangshui Luo; Jin Hu; Wolfgang Saak; Rüdiger
Beckhaus; Gunther Wittstock; Ivo F. J. Vankelecom; Carsten Agert; Olaf Conrad (2011).
839:
875:
270:
being the most popular model. PEM fuel cells have seen successful implementation in other forms of heavy machinery as well, with
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378:
1522:
1393:
911:
307:
1222:
712:
Hu, S.; Lozado-Hidalgo, M.; Wang, F.C.; et al. (26 November 2014). "Proton transport through one atom thick crystals".
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266:
below-freezing conditions. As of March 2019 there were 6,558 fuel cell vehicles on the road in the United States, with the
1433:
1024:
Li, Mengxiao; Bai, Yunfeng; Zhang, Caizhi; Song, Yuxi; Jiang, Shangfeng; Grouset, Didier; Zhang, Mingjun (23 April 2019).
487:
1527:
1316:
1176:"Air Liquide invests in the world's largest membrane-based electrolyzer to develop its carbon-free hydrogen production"
1486:
1403:
1346:
347:
322:
94:
52:
461:
63:: separation of reactants and transport of protons while blocking a direct electronic pathway through the membrane.
1423:
1285:
297:
PEM electrolyzer plant in Québec. Similar PEM-based devices are available for the industrial production of ozone.
128:. Significant government resources were devoted to the study and development of these membranes for use in NASA's
1512:
1413:
1331:
1290:
1326:
1250:
342:
153:
145:
plastics chemist
Walther Grot. Grot also demonstrated its usefulness as an electrochemical separator membrane.
1203:, "PEM (proton exchange membrane) low-voltage electrolysis ozone generating device", issued 2011-05-16
659:
1408:
1341:
1321:
337:
142:
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519:"Batteries with Solid Ion-Exchange Membrane Electrolytes: II . Low-Temperature Hydrogen-Oxygen Fuel Cells"
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32:
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1080:"Fact of the Month March 2019: There Are More Than 6,500 Fuel Cell Vehicles On the Road in the U.S."
1507:
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332:
312:
189:
120:
Leonard
Niedrach (left) and Thomas Grubb (right), inventors of proton-exchange membrane technology.
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71:
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141:, which is today the most widely utilized proton-exchange membrane material, was developed by
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1026:"Review on the research of hydrogen storage system fast refueling in fuel cell vehicle"
134:
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562:. Advances in Chemistry. Vol. 47. WASHINGTON, D.C.: AMERICAN CHEMICAL SOCIETY.
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818:
761:
357:
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1128:
Carmo, Marcelo; Fritz, David L.; Mergel, Jürgen; Stolten, Detlef (22 April 2013).
462:"New Proton Exchange Membrane Developed – Nafion promises inexpensive fuel-cells"
294:
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290:
149:
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999:
611:
542:
488:"Research Topics for Materials and Processes for PEM Fuel Cells REU for 2008"
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product. While Nafion is an ionomer with a perfluorinated backbone like
924:
888:
852:
67:
36:
534:
43:
while acting as an electronic insulator and reactant barrier, e.g. to
868:"Imidazolium methanesulfonate as a high temperature proton conductor"
285:
hydrogen fuel and oxygen for life-support systems in vessels such as
138:
87:
83:
79:
44:
990:
965:
172:
PEMFCs have some advantages over other types of fuel cells such as
1228:
EC-supported STREP program on high pressure PEM water electrolysis
728:
390:
93:
Proton-exchange membranes are primarily characterized by proton
1239:
633:"Collecting the History of Proton Exchange Membrane Fuel Cells"
51:
gas. This is their essential function when incorporated into a
1235:
192:, are actively studied for the development of suitable PEMs.
293:
submarines. A recent example is the construction of a 20 MW
556:
Young, George J.; Linden, Henry R., eds. (1 January 1969).
380:
Alternative electrochemical systems for ozonation of water
1104:"Material Handling – Fuel Cell Solutions | Ballard Power"
866:
Jiangshui Luo, Olaf Conrad; Ivo F. J. Vankelecom (2013).
249:
The theoretical exothermic potential is +1.23 V overall.
414:"Novel inorganic/organic hybrid electrolyte membranes"
156:
published initial results on atom thick monolayers of
133:
Gemini missions, but was abandoned for the subsequent
966:"Status and development of PEM fuel cell technology"
1449:
1381:
1360:
1309:
1273:
1130:"A comprehensive review on PEM water electrolysis"
517:Grubb, W. T.; Niedrach, L. W. (1 February 1960).
1251:
8:
1258:
1244:
1236:
421:Prepr. Pap.-Am. Chem. Soc., Div. Fuel Chem
16:Ion-exchange membrane specific for protons
989:
939:"Could This Hydrogen-Powered Drone Work?"
800:
727:
282:Polymer electrolyte membrane electrolysis
1134:International Journal of Hydrogen Energy
1030:International Journal of Hydrogen Energy
970:International Journal of Energy Research
115:
370:
694:
684:
523:Journal of the Electrochemical Society
1223:Dry solid polymer electrolyte battery
1019:
1017:
775:Karnik, Rohit N. (26 November 2014).
627:
625:
623:
621:
353:Proton exchange membrane electrolysis
61:proton-exchange membrane electrolyser
7:
1296:Proton-exchange membrane fuel cell
840:Energy & Environmental Science
661:Fluorinated Ionomers – 2nd Edition
460:Gabriel Gache (17 December 2007).
137:missions. The fluorinated ionomer
66:PEMs can be made from either pure
57:proton-exchange membrane fuel cell
14:
412:Zhiwei Yang; et al. (2004).
876:Journal of Materials Chemistry A
1439:Unitized regenerative fuel cell
1182:. Air Liquide. 25 February 2019
964:Barbir, F.; Yazici, S. (2008).
1154:10.1016/j.ijhydene.2013.01.151
1050:10.1016/j.ijhydene.2019.02.208
912:Journal of Materials Chemistry
658:Grot, Walther (15 July 2011).
596:The American Historical Review
308:Alkali anion exchange membrane
1:
1434:Solid oxide electrolyzer cell
1317:Direct borohydride fuel cell
243:O + heat + electrical energy
25:polymer-electrolyte membrane
1404:Membrane electrode assembly
1347:Reformed methanol fuel cell
348:Membrane electrode assembly
323:Dynamic mechanical analysis
53:membrane electrode assembly
1549:
1424:Protonic ceramic fuel cell
1394:Electro-galvanic fuel cell
1286:Molten carbonate fuel cell
777:"Breakthrough for protons"
393:. 20 March 2007. MSC-23045
105:), and thermal stability.
1482:
1414:Photoelectrochemical cell
1332:Direct methanol fuel cell
1291:Phosphoric acid fuel cell
639:. Smithsonian Institution
1419:Proton-exchange membrane
1327:Direct-ethanol fuel cell
343:Isotope electrochemistry
154:University of Manchester
126:General Electric Company
21:proton-exchange membrane
1409:Membraneless Fuel Cells
1342:Metal hydride fuel cell
1322:Direct carbon fuel cell
338:Gas diffusion electrode
228:Overall cell reaction:
1429:Regenerative fuel cell
1368:Enzymatic biofuel cell
637:americanhistory.si.edu
174:solid oxide fuel cells
121:
33:semipermeable membrane
1523:Hydrogen technologies
1337:Formic acid fuel cell
1301:Solid oxide fuel cell
439:US patent 5266421
328:Electrolysis of water
272:Ballard Power Systems
119:
604:10.1086/ahr/84.2.593
568:10.1021/ba-1965-0047
486:Nakhiah Goulbourne.
389:(Technical report).
190:protic ionic liquids
35:generally made from
1528:Membrane technology
1373:Microbial fuel cell
1146:2013IJHE...38.4901C
1042:2019IJHE...4410677L
1036:(21): 10677–10693.
982:2008IJER...32..369B
919:(28): 10426–10436.
802:10.1038/nature14074
793:2014Natur.516..173K
746:10.1038/nature14015
738:2014Natur.516..227H
498:on 27 February 2009
333:Electroosmotic pump
313:Artificial membrane
1281:Alkaline fuel cell
925:10.1039/C0JM04306K
889:10.1039/C2TA00713D
853:10.1039/C4EE02280G
664:. William Andrew.
212:Cathode reaction:
122:
70:membranes or from
1495:
1494:
1140:(12): 4901–4934.
787:(7530): 173–174.
671:978-1-4377-4457-6
577:978-0-8412-0048-7
559:Fuel Cell Systems
535:10.1149/1.2427622
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1513:Electrochemistry
1352:Zinc–air battery
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494:. Archived from
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200:Anode reaction:
39:and designed to
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976:(5): 369–378.
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598:. April 1979.
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