1756:
the cathode, oxygen can be catalytically reacted with hydrogen on the platinum surface of the cathodic catalyst. At the anode, hydrogen and oxygen do not react at the iridium oxide catalyst. Thus, safety hazards due to explosive anodic mixtures hydrogen in oxygen can result. The supplied energy for the hydrogen production is lost, when hydrogen is lost due to the reaction with oxygen at the cathode and permeation from the cathode across the membrane to the anode corresponds. Hence, the ratio of the amount of lost and produced hydrogen determines the faradaic losses. At pressurized operation of the electrolyzer, the crossover and the correlated faradaic efficiency losses increase.
1607:
1313:. The calculation of cell voltage assuming no irreversibilities exist and all of the thermal energy is utilized by the reaction is referred to as the lower heating value (LHV). The alternative formulation, using the higher heating value (HHV) is calculated assuming that all of the energy to drive the electrolysis reaction is supplied by the electrical component of the required energy which results in a higher reversible cell voltage. When using the HHV the voltage calculation is referred to as the
1821:
1807:
603:
29:
1791:
higher overall electrical efficiency. The LHV must be used for alkaline electrolysers as the process within these electrolysers requires water in liquid form and uses alkalinity to facilitate the breaking of the bond holding the hydrogen and oxygen atoms together. The lower heat value must also be used for fuel cells, as steam is the output rather than input.
1774:
1782:
coupling these to energy sources such as wind and solar, the demand of the grid rarely matches the generation of renewable energy. This means energy produced from renewable sources such as wind and solar benefit by having a buffer, or a means of storing off-peak energy. As of 2021, the largest PEM electrolyzer is 20 MW.
1682:. Much of this heat energy is carried away with the reactant water supply and lost to the environment, however a small portion of this energy is then recaptured as heat energy in the electrolysis process. The amount of heat energy that can be recaptured is dependent on many aspects of system operation and cell design.
300:
An electrolyzer is an electrochemical device to convert electricity and water into hydrogen and oxygen, these gases can then be used as a means to store energy for later use. This use can range from electrical grid stabilization from dynamic electrical sources such as wind turbines and solar cells to
1764:
Hydrogen evolution due to pressurized electrolysis is comparable to an isothermal compression process, which is in terms of efficiency preferable compared to mechanical isotropic compression. However, the contributions of the aforementioned faradaic losses increase with operating pressures. Thus, in
1755:
Faradaic losses describe the efficiency losses that are correlated to the current, that is supplied without leading to hydrogen at the cathodic gas outlet. The produced hydrogen and oxygen can permeate across the membrane, referred to as crossover. Mixtures of both gases at the electrodes result. At
1449:
1794:
PEM electrolysis has an electrical efficiency of about 80% in working application, in terms of hydrogen produced per unit of electricity used to drive the reaction. The efficiency of PEM electrolysis is expected to reach 82-86% before 2030, while also maintaining durability as progress in this area
1262:
1790:
When determining the electrical efficiency of PEM electrolysis, the HHV can be used. This is because the catalyst layer interacts with water as steam. As the process operates at 80 °C for PEM electrolysers the waste heat can be redirected through the system to create the steam, resulting in a
263:
One of the largest advantages to PEM electrolysis is its ability to operate at high current densities. This can result in reduced operational costs, especially for systems coupled with very dynamic energy sources such as wind and solar, where sudden spikes in energy input would otherwise result in
330:
The actual value for open circuit voltage of an operating electrolyzer will lie between the 1.23 V and 1.48 V depending on how the cell/stack design utilizes the thermal energy inputs. This is however quite difficult to determine or measure because an operating electrolyzer also experiences other
1781:
The ability of the PEM electrolyzer to operate, not only under highly dynamic conditions but also in part-load and overload conditions is one of the reasons for the recently renewed interest in this technology. The demands of an electrical grid are relatively stable and predictable, however when
222:
in a cell equipped with a solid polymer electrolyte (SPE) that is responsible for the conduction of protons, separation of product gases, and electrical insulation of the electrodes. The PEM electrolyzer was introduced to overcome the issues of partial load, low current density, and low pressure
251:
technology of that time, very efficient. In the late 1970s the alkaline electrolyzers were reporting performances around 0.215 A/cm at 2.06 V, thus prompting a sudden interest in the late 1970s and early 1980s in polymer electrolytes for water electrolysis. PEM water electrolysis technology is
237:
to be used as an energy carrier. With fast dynamic response times, large operational ranges, and high efficiencies, water electrolysis is a promising technology for energy storage coupled with renewable energy sources. In terms of sustainability and environmental impact, PEM electrolysis is
1090:
The thermal and electrical inputs shown above represent the minimum amount of energy that can be supplied by electricity in order to obtain an electrolysis reaction. Assuming that the maximum amount of heat energy (48.6 kJ/mol) is supplied to the reaction, the reversible cell voltage
264:
uncaptured energy. The polymer electrolyte allows the PEM electrolyzer to operate with a very thin membrane (~100-200 μm) while still allowing high pressures, resulting in low ohmic losses, primarily caused by the conduction of protons across the membrane (0.1 S/cm) and a
487:
The half reaction taking place on the cathode side of a PEM electrolyzer is commonly referred to as the
Hydrogen Evolution Reaction (HER). Here the supplied electrons and the protons that have conducted through the membrane are combined to create gaseous hydrogen.
271:
The polymer electrolyte membrane, due to its solid structure, exhibits a low gas crossover rate resulting in very high product gas purity. Maintaining a high gas purity is important for storage safety and for the direct usage in a fuel cell. The safety limits for
343:
The half reaction taking place on the anode side of a PEM electrolyzer is commonly referred to as the Oxygen
Evolution Reaction (OER). Here the liquid water reactant is supplied to catalyst where the supplied water is oxidized to oxygen, protons and electrons.
708:
594:
The illustration below depicts a simplification of how PEM electrolysis works, showing the individual half-reactions together along with the complete reaction of a PEM electrolyzer. In this case the electrolyzer is coupled with a solar panel for the
246:
The use of a PEM for electrolysis was first introduced in the 1960s by
General Electric, developed to overcome the drawbacks to the alkaline electrolysis technology. The initial performances yielded 1.0 A/cm at 1.88 V which was, compared to the
1562:
1325:
1138:
1465:, is typically compared through polarization curves, which are obtained by plotting cell voltages against current densities. The primary sources of increased voltage in a PEM electrolyzer (the same also applies for
321:
required for the decomposition of water is 285.9 kJ/mol. A portion of the required energy for a sustained electrolysis reaction is supplied by thermal energy and the remainder is supplied through electrical energy.
238:
considered as a promising technique for high purity and efficient hydrogen production since it emits only oxygen as a by-product without any carbon emissions. The IEA said in 2022 that more effort was needed.
472:
1677:
The energy loss due to the electrical resistance is not entirely lost. The voltage drop due to resistivity is associated with the conversion the electrical energy to heat energy through a process known as
893:
2387:
255:
A thorough review of the historical performance from the early research to that of today can be found in chronological order with many of the operating conditions in the 2013 review by Carmo et al.
1619:
Ohmic losses are an electrical overpotential introduced to the electrolysis process by the internal resistance of the cell components. This loss then requires an additional voltage to maintain the
585:
1477:
and mass transport losses. Due to the reversal of operation between a PEM fuel cell and a PEM electrolyzer, the degree of impact for these various losses is different between the two processes.
1081:
1726:
1123:
633:
1765:
order to produce compressed hydrogen, the in-situ compression during electrolysis and subsequent compression of the gas have to be pondered under efficiency considerations.
1668:
785:
738:
2492:
1487:
1599:
of a 25 cm single cell PEM electrolyzer under thermoneutral operation depicting the primary sources of voltage loss and their contributions for a range of
1307:
1287:
762:
2379:
1444:{\displaystyle V_{\textrm {th}}^{0}={\frac {\Delta H^{0}}{n\cdot F}}={\frac {285.9\ {\textrm {kJ/mol}}}{2\times 96,485\ {\textrm {C/mol}}}}=1.48{\textrm {V}}}
1257:{\displaystyle V_{\textrm {rev}}^{0}={\frac {\Delta G^{0}}{n\cdot F}}={\frac {237\ {\textrm {kJ/mol}}}{2\times 96,485\ {\textrm {C/mol}}}}=1.23{\textrm {V}}}
2025:
2432:
2013:
252:
similar to PEM fuel cell technology, where solid poly-sulfonated membranes, such as nafion, fumapem, were used as a electrolyte (proton conductor).
2467:
2284:
Schröder, V; Emonts B; Janßen H; Schulze HP (2004). "Explosion Limits of
Hydrogen/Oxygen Mixtures at Initial Pressures up to 200 bar".
355:
2351:
2349:
Schalenbach, M; Carmo M; Fritz DL; Mergel J; Stolten D (2013). "Pressurized PEM water electrolysis: Efficiency and gas crossover".
2311:
Mergel, J; Carmo M; Fritz, D (2013). "Status on
Technologies for Hydrogen Production by Water Electrolysis". In Stolten, D (ed.).
801:
2324:
2235:
498:
1575:. This essentially results in a curve that represents the power per square centimeter of cell area required to produce
1870:
2152:
LeRoy, RL; Janjua MB; Renaud R; Leuenberger U (1979). "Analysis of Time-Variation
Effects in Water Electrolyzers".
2137:
Russell, JH; Nuttall LJ; Ficket AP (1973). "Hydrogen generation by solid polymer electrolyte water electrolysis".
912:
2521:
2032:
2189:"An overview of polymer electrolyte membrane electrolyzer for hydrogen production: Modeling and mass transport"
1860:
318:
703:{\displaystyle \Delta H=\underbrace {\Delta G} _{\textrm {elec.}}+\underbrace {T\Delta S} _{\textrm {heat}}}
2565:
1692:
1094:
616:
1735:
The Ohmic losses due to the conduction of protons contribute to the loss of efficiency which also follows
2570:
2402:
1840:
2456:
1596:
1890:
2188:
2560:
313:
to conduct protons from the anode to the cathode while insulating the electrodes electrically. Under
1946:
Carmo, M; Fritz D; Mergel J; Stolten D (2013). "A comprehensive review on PEM water electrolysis".
1744:
310:
224:
1747:
is very dependent on the hydration, temperature, heat treatment, and ionic state of the membrane.
1826:
1641:
335:, proton conductivity, mass transport through the cell and catalyst utilization to name a few.
234:
1610:
Polarization curve depicting the various losses attributed to PEM electrolysis cell operation.
1571:
A PEM electrolysis system's performance can be compared by plotting overpotential versus cell
767:
720:
2555:
1875:
1314:
332:
248:
230:
219:
1557:{\displaystyle V_{\textrm {cell}}=E+V_{\textrm {act}}+V_{\textrm {trans}}+V_{\textrm {ohm}}}
2250:
2200:
2161:
2069:
8:
1850:
1588:
596:
314:
302:
265:
2254:
2204:
2187:
Abdol Rahim, A. H.; Tijani, Alhassan Salami; Kamarudin, S. K.; Hanapi, S. (2016-03-31).
2165:
2073:
2266:
2095:
1996:
1865:
1292:
1272:
747:
306:
2320:
2216:
2099:
2087:
2000:
1975:"An analysis of PEM water electrolysis cells operating at elevated current densities"
741:
2270:
2364:
2360:
2293:
2258:
2212:
2208:
2169:
2077:
1991:
1986:
1974:
1959:
1955:
1885:
1835:
1310:
1606:
1773:
1628:
1600:
1592:
1572:
2082:
2057:
2549:
2220:
2091:
1880:
1812:
1740:
1679:
1584:
1474:
1466:
281:
2113:
599:, however the solar panel could be replaced with any source of electricity.
2380:"World's largest green-hydrogen plant inaugurated in Canada by Air Liquide"
2297:
1845:
1620:
1855:
902:
The overall cell reaction with thermodynamic energy inputs then becomes:
2433:"RWE's former, current and possible future energy storage applications"
1470:
1462:
606:
Diagram of PEM electrolyzer cell and the basic principles of operation.
2262:
2236:"Ionic conductivity of an extruded Nafion 1100 EW series of membranes"
2173:
223:
operation currently plaguing the alkaline electrolyzer. It involves a
2316:
949:
1820:
989:
602:
2151:
1736:
1624:
1576:
620:
2348:
2283:
28:
1806:
1759:
788:
467:{\displaystyle {\ce {2 H2O (l) -> O2 (g) + 4H+ (aq) + 4 e^-}}}
2233:
2186:
2026:"2014 - Development of water electrolysis in the European Union"
1580:
2493:"Cost reduction and performance increase of PEM electrolysers"
2139:
American
Chemical Society Division of Fuel Chemistry Preprints
1945:
888:{\displaystyle {\ce {H2O (l) + \Delta H -> H2 + 1/2 O2}}}
2457:"ITM – Hydrogen Refuelling Infrastructure – February 2017"
2136:
2058:"Hydrogen production by PEM water electrolysis – A review"
1595:. The figure below is the result of a simulation from the
2439:
1069:
1042:
927:
881:
855:
816:
562:
404:
374:
1049:
861:
580:{\displaystyle {\ce {4H+ (aq) + 4 e^- -> 2H2 (g)}}}
2310:
1695:
1644:
1490:
1328:
1295:
1275:
1141:
1097:
915:
804:
770:
750:
723:
636:
501:
358:
2055:
1802:
2444:
Total
Efficiency: 70%, or 86% (usage of waste heat)
2344:
2342:
2340:
2338:
2336:
2234:Slade, S; Campbell SA; Ralph TR; Walsh FC (2002).
1720:
1662:
1556:
1443:
1301:
1281:
1256:
1117:
1075:
887:
779:
756:
732:
702:
579:
466:
2547:
2333:
1972:
1750:
1587:, the better the PEM electrolyzer the lower the
2522:"Report and Financial Statements 30 April 2016"
610:
2277:
1760:Hydrogen compression during water electrolysis
1623:reaction, the prediction of this loss follows
2056:Shiva Kumar, S.; Himabindu, V. (2019-12-01).
1941:
1939:
1937:
1935:
1933:
1931:
1929:
1927:
1128:
1076:{\displaystyle {\ce {H2O(l)->{H2}+1/2O2}}}
1925:
1923:
1921:
1919:
1917:
1915:
1913:
1911:
1909:
1907:
1469:) can be categorized into three main areas,
1461:The performance of electrolysis cells, like
233:of water is an important technology for the
2502:. Fuel Cells and Hydrogen Joint Undertaking
2304:
2227:
2014:2012 - PEM water electrolysis fundamentals
2081:
2062:Materials Science for Energy Technologies
1990:
1904:
551:
534:
506:
452:
424:
363:
2430:
2352:International Journal of Hydrogen Energy
1979:International Journal of Hydrogen Energy
1948:International Journal of Hydrogen Energy
1772:
1605:
601:
16:Technology for splitting water molecules
2384:Recharge | Latest renewable energy news
2377:
2371:
1743:effect. The proton conductivity of the
1627:and holds a linear relationship to the
764:is the temperature of the reaction and
2548:
2313:Transition to Renewable Energy Systems
2243:Journal of the Electrochemical Society
2154:Journal of the Electrochemical Society
33:Diagram of PEM electrolysis reactions.
2286:Chemical Engineering & Technology
1777:PEM high pressure electrolyzer system
1721:{\displaystyle Q\propto I^{2}\cdot R}
1118:{\displaystyle V_{\textrm {rev}}^{0}}
22:Proton exchange membrane electrolysis
2431:Bernholz, Jan (September 13, 2018).
2390:from the original on 25 March 2021.
1768:
482:
13:
2473:from the original on 17 April 2018
2378:Collins, Leigh (27 January 2021).
1352:
1165:
836:
771:
724:
680:
650:
637:
309:. The PEM electrolyzer utilizes a
280:are at standard conditions 4
163:Specific energy consumption system
14:
2582:
2400:
1871:Timeline of hydrogen technologies
1785:
1456:
338:
155:Specific energy consumption stack
102:State-of-the-art Operating Ranges
1819:
1805:
78:Catalyst material on the cathode
60:Bipolar/separator plate material
27:
2514:
2485:
2449:
2424:
2403:"Hydrogen Status og muligheter"
2394:
1631:of the operating electrolyzer.
1614:
1289:is the number of electrons and
311:solid polymer electrolyte (SPE)
179:System hydrogen production rate
2365:10.1016/j.ijhydene.2013.09.013
2213:10.1016/j.jpowsour.2016.01.012
2180:
2145:
2130:
2106:
2049:
2018:
2007:
1992:10.1016/j.ijhydene.2018.11.179
1973:Villagra, A; Millet P (2019).
1966:
1960:10.1016/j.ijhydene.2013.01.151
1861:Photocatalytic water splitting
940:
934:
842:
829:
823:
572:
566:
545:
524:
518:
442:
436:
414:
408:
391:
387:
381:
70:Catalyst material on the anode
1:
1897:
1751:Faradaic losses and crossover
331:voltage losses from internal
258:
617:second law of thermodynamics
611:Second law of thermodynamics
325:
7:
1841:Electrochemical engineering
1798:
195:Acceptable degradation rate
52:Style of membrane/diaphragm
10:
2587:
2114:"Electrolysers – Analysis"
2083:10.1016/j.mset.2019.03.002
1891:High-pressure electrolysis
1663:{\displaystyle V=I\cdot R}
1129:Open circuit voltage (OCV)
295:
241:
97:Carbon paper/carbon fleece
2520:
2455:
202:
194:
186:
178:
170:
162:
154:
146:
138:
130:
122:
114:
106:
101:
93:
85:
77:
69:
59:
51:
43:
38:
26:
21:
2491:
2193:Journal of Power Sources
1597:Forschungszentrum Jülich
780:{\displaystyle \Delta S}
733:{\displaystyle \Delta G}
225:proton-exchange membrane
213:Proton exchange membrane
65:platinum coated titanium
1827:Renewable energy portal
171:Cell voltage efficiency
2298:10.1002/ceat.200403174
1778:
1739:, however without the
1722:
1664:
1611:
1558:
1445:
1303:
1283:
1258:
1119:
1077:
1029:
889:
781:
758:
734:
704:
607:
597:production of hydrogen
581:
468:
333:electrical resistances
235:production of hydrogen
1876:Electrolysis of water
1795:continues at a pace.
1776:
1723:
1665:
1609:
1559:
1446:
1315:thermoneutral voltage
1304:
1284:
1259:
1120:
1078:
945:
890:
782:
759:
735:
705:
605:
582:
469:
249:alkaline electrolysis
220:electrolysis of water
63:Titanium or gold and
44:Type of Electrolysis:
1693:
1642:
1583:. Conversely to the
1488:
1326:
1293:
1273:
1139:
1095:
913:
802:
768:
748:
721:
634:
623:of the reaction is:
499:
356:
94:Cathode PTL material
2566:Hydrogen production
2359:(35): 14921–14933.
2255:2002JElS..149A1556S
2205:2016JPS...309...56A
2166:1979JElS..126.1674L
2074:2019MSET....2..442S
1851:Hydrogen production
1345:
1158:
1125:can be calculated.
1114:
1071:
1044:
1028:
988:
929:
883:
857:
818:
564:
406:
376:
315:standard conditions
303:hydrogen production
266:compressed hydrogen
2571:Electrolytic cells
1866:Water purification
1779:
1718:
1660:
1612:
1554:
1441:
1329:
1311:Faraday's constant
1299:
1279:
1254:
1142:
1115:
1098:
1073:
1059:
1058:
1032:
987:
980:
917:
885:
871:
870:
845:
806:
777:
754:
730:
700:
699:
690:
669:
660:
608:
577:
552:
464:
394:
364:
307:fuel cell vehicles
216:(PEM) electrolysis
86:Anode PTL material
2529:www.itm-power.com
2500:www.fch.europa.eu
2464:level-network.com
2326:978-3-527-33239-7
2263:10.1149/1.1517281
2174:10.1149/1.2128775
1985:(20): 9708–9717.
1954:(12): 4901–4934.
1731:
1730:
1673:
1672:
1601:current densities
1567:
1566:
1550:
1535:
1520:
1499:
1475:activation losses
1454:
1453:
1438:
1426:
1422:
1417:
1395:
1390:
1377:
1337:
1302:{\displaystyle F}
1282:{\displaystyle n}
1267:
1266:
1251:
1239:
1235:
1230:
1208:
1203:
1190:
1150:
1106:
1086:
1085:
1062:
1057:
1035:
1027:
1025:
1020:
1014:
1006:
1002:
985:
974:
966:
962:
955:
953:
939:
932:
920:
898:
897:
874:
869:
848:
841:
828:
821:
809:
787:is the change in
757:{\displaystyle T}
744:of the reaction,
742:Gibbs free energy
713:
712:
696:
675:
673:
666:
648:
646:
590:
589:
571:
555:
538:
523:
510:
478:
477:
456:
441:
428:
413:
397:
386:
379:
367:
210:
209:
39:Typical Materials
2578:
2561:Hydrogen economy
2540:
2539:
2537:
2535:
2526:
2518:
2512:
2511:
2509:
2507:
2497:
2489:
2483:
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2447:
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2437:
2428:
2422:
2421:
2419:
2417:
2412:. Bellona Norway
2407:
2401:Kruse, Bjørnar.
2398:
2392:
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2368:
2346:
2331:
2330:
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2301:
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2274:
2240:
2231:
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2224:
2184:
2178:
2177:
2149:
2143:
2142:
2134:
2128:
2127:
2125:
2124:
2110:
2104:
2103:
2085:
2053:
2047:
2046:
2044:
2043:
2037:
2031:. Archived from
2030:
2022:
2016:
2011:
2005:
2004:
1994:
1970:
1964:
1963:
1943:
1886:Hydrogen economy
1836:Electrochemistry
1829:
1824:
1823:
1815:
1810:
1809:
1769:System operation
1727:
1725:
1724:
1719:
1711:
1710:
1687:
1686:
1669:
1667:
1666:
1661:
1636:
1635:
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1300:
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1189:
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1177:
1176:
1163:
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1148:
1133:
1132:
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1121:
1116:
1113:
1108:
1107:
1104:
1082:
1080:
1079:
1074:
1072:
1070:
1067:
1060:
1050:
1045:
1043:
1040:
1033:
1030:
1026:
1023:
1021:
1016:
1015:
1012:
1011:
1004:
1000:
995:
993:
986:
983:
981:
976:
975:
972:
971:
964:
960:
943:
937:
930:
928:
925:
918:
907:
906:
894:
892:
891:
886:
884:
882:
879:
872:
862:
856:
853:
846:
839:
832:
826:
819:
817:
814:
807:
796:
795:
786:
784:
783:
778:
763:
761:
760:
755:
739:
737:
736:
731:
709:
707:
706:
701:
698:
697:
694:
691:
686:
668:
667:
664:
661:
656:
628:
627:
586:
584:
583:
578:
576:
575:
569:
563:
560:
553:
544:
543:
536:
527:
521:
516:
515:
508:
493:
492:
483:Cathode reaction
473:
471:
470:
465:
463:
462:
461:
454:
445:
439:
434:
433:
426:
417:
411:
405:
402:
395:
390:
384:
377:
375:
372:
365:
349:
348:
107:Cell temperature
47:PEM Electrolysis
31:
19:
18:
2586:
2585:
2581:
2580:
2579:
2577:
2576:
2575:
2546:
2545:
2544:
2543:
2533:
2531:
2524:
2519:
2515:
2505:
2503:
2495:
2490:
2486:
2476:
2474:
2470:
2459:
2454:
2450:
2435:
2429:
2425:
2415:
2413:
2405:
2399:
2395:
2376:
2372:
2347:
2334:
2327:
2309:
2305:
2282:
2278:
2238:
2232:
2228:
2185:
2181:
2150:
2146:
2135:
2131:
2122:
2120:
2112:
2111:
2107:
2054:
2050:
2041:
2039:
2035:
2028:
2024:
2023:
2019:
2012:
2008:
1971:
1967:
1944:
1905:
1900:
1895:
1825:
1818:
1811:
1804:
1801:
1788:
1771:
1762:
1753:
1706:
1702:
1694:
1691:
1690:
1643:
1640:
1639:
1629:current density
1617:
1593:current density
1573:current density
1547:
1546:
1542:
1532:
1531:
1527:
1517:
1516:
1512:
1496:
1495:
1491:
1489:
1486:
1485:
1459:
1435:
1434:
1419:
1418:
1399:
1392:
1391:
1384:
1382:
1366:
1359:
1355:
1351:
1349:
1340:
1334:
1333:
1327:
1324:
1323:
1294:
1291:
1290:
1274:
1271:
1270:
1248:
1247:
1232:
1231:
1212:
1205:
1204:
1197:
1195:
1179:
1172:
1168:
1164:
1162:
1153:
1147:
1146:
1140:
1137:
1136:
1131:
1109:
1103:
1102:
1096:
1093:
1092:
1068:
1063:
1041:
1036:
1031:
1022:
1007:
1003:
996:
994:
982:
967:
963:
956:
954:
944:
933:
926:
921:
916:
914:
911:
910:
880:
875:
854:
849:
822:
815:
810:
805:
803:
800:
799:
791:of the system.
769:
766:
765:
749:
746:
745:
722:
719:
718:
693:
692:
676:
674:
663:
662:
649:
647:
635:
632:
631:
613:
565:
561:
556:
539:
535:
517:
511:
507:
502:
500:
497:
496:
485:
457:
453:
435:
429:
425:
407:
403:
398:
380:
373:
368:
359:
357:
354:
353:
341:
328:
298:
291:
287:
279:
275:
261:
244:
203:System lifetime
147:Part-load range
123:Current density
64:
34:
17:
12:
11:
5:
2584:
2574:
2573:
2568:
2563:
2558:
2542:
2541:
2513:
2484:
2448:
2442:. p. 10.
2423:
2393:
2370:
2332:
2325:
2303:
2292:(8): 847–851.
2276:
2226:
2179:
2144:
2129:
2105:
2068:(3): 442–454.
2048:
2017:
2006:
1965:
1902:
1901:
1899:
1896:
1894:
1893:
1888:
1883:
1878:
1873:
1868:
1863:
1858:
1853:
1848:
1843:
1838:
1832:
1831:
1830:
1816:
1800:
1797:
1787:
1786:PEM efficiency
1784:
1770:
1767:
1761:
1758:
1752:
1749:
1733:
1732:
1729:
1728:
1717:
1714:
1709:
1705:
1701:
1698:
1675:
1674:
1671:
1670:
1659:
1656:
1653:
1650:
1647:
1616:
1613:
1569:
1568:
1565:
1564:
1545:
1541:
1530:
1526:
1515:
1511:
1508:
1505:
1494:
1467:PEM fuel cells
1458:
1457:Voltage losses
1455:
1452:
1451:
1433:
1430:
1414:
1411:
1408:
1405:
1402:
1387:
1381:
1375:
1372:
1369:
1362:
1358:
1354:
1348:
1343:
1332:
1298:
1278:
1265:
1264:
1246:
1243:
1227:
1224:
1221:
1218:
1215:
1200:
1194:
1188:
1185:
1182:
1175:
1171:
1167:
1161:
1156:
1145:
1130:
1127:
1112:
1101:
1088:
1087:
1084:
1083:
1066:
1056:
1053:
1048:
1039:
1019:
1010:
999:
992:
979:
970:
959:
952:
948:
942:
936:
924:
900:
899:
896:
895:
878:
868:
865:
860:
852:
844:
838:
835:
831:
825:
813:
776:
773:
753:
729:
726:
715:
714:
711:
710:
689:
685:
682:
679:
672:
659:
655:
652:
645:
642:
639:
612:
609:
592:
591:
588:
587:
574:
568:
559:
550:
547:
542:
533:
530:
526:
520:
514:
505:
484:
481:
480:
479:
476:
475:
460:
451:
448:
444:
438:
432:
423:
420:
416:
410:
401:
393:
389:
383:
371:
362:
340:
339:Anode reaction
337:
327:
324:
305:as a fuel for
297:
294:
289:
285:
277:
273:
260:
257:
243:
240:
208:
207:
204:
200:
199:
196:
192:
191:
188:
187:Lifetime stack
184:
183:
180:
176:
175:
172:
168:
167:
166:4.5-7.5 kWh/Nm
164:
160:
159:
158:4.2-5.6 kWh/Nm
156:
152:
151:
148:
144:
143:
140:
136:
135:
132:
128:
127:
124:
120:
119:
116:
115:Stack pressure
112:
111:
108:
104:
103:
99:
98:
95:
91:
90:
87:
83:
82:
79:
75:
74:
71:
67:
66:
61:
57:
56:
53:
49:
48:
45:
41:
40:
36:
35:
32:
24:
23:
15:
9:
6:
4:
3:
2:
2583:
2572:
2569:
2567:
2564:
2562:
2559:
2557:
2554:
2553:
2551:
2530:
2523:
2517:
2501:
2494:
2488:
2469:
2465:
2458:
2452:
2445:
2441:
2434:
2427:
2411:
2404:
2397:
2389:
2385:
2381:
2374:
2366:
2362:
2358:
2354:
2353:
2345:
2343:
2341:
2339:
2337:
2328:
2322:
2318:
2314:
2307:
2299:
2295:
2291:
2287:
2280:
2272:
2268:
2264:
2260:
2256:
2252:
2249:(12): A1556.
2248:
2244:
2237:
2230:
2222:
2218:
2214:
2210:
2206:
2202:
2198:
2194:
2190:
2183:
2175:
2171:
2167:
2163:
2159:
2155:
2148:
2140:
2133:
2119:
2115:
2109:
2101:
2097:
2093:
2089:
2084:
2079:
2075:
2071:
2067:
2063:
2059:
2052:
2038:on 2015-03-31
2034:
2027:
2021:
2015:
2010:
2002:
1998:
1993:
1988:
1984:
1980:
1976:
1969:
1961:
1957:
1953:
1949:
1942:
1940:
1938:
1936:
1934:
1932:
1930:
1928:
1926:
1924:
1922:
1920:
1918:
1916:
1914:
1912:
1910:
1908:
1903:
1892:
1889:
1887:
1884:
1882:
1881:PEM fuel cell
1879:
1877:
1874:
1872:
1869:
1867:
1864:
1862:
1859:
1857:
1854:
1852:
1849:
1847:
1844:
1842:
1839:
1837:
1834:
1833:
1828:
1822:
1817:
1814:
1813:Energy portal
1808:
1803:
1796:
1792:
1783:
1775:
1766:
1757:
1748:
1746:
1742:
1741:Joule heating
1738:
1715:
1712:
1707:
1703:
1699:
1696:
1689:
1688:
1685:
1684:
1683:
1681:
1680:Joule heating
1657:
1654:
1651:
1648:
1645:
1638:
1637:
1634:
1633:
1632:
1630:
1626:
1622:
1608:
1604:
1602:
1598:
1594:
1590:
1586:
1585:PEM fuel cell
1582:
1578:
1574:
1543:
1539:
1528:
1524:
1513:
1509:
1506:
1503:
1492:
1484:
1483:
1480:
1479:
1478:
1476:
1472:
1468:
1464:
1431:
1428:
1412:
1409:
1406:
1403:
1400:
1385:
1379:
1373:
1370:
1367:
1360:
1356:
1346:
1341:
1330:
1322:
1321:
1318:
1316:
1312:
1296:
1276:
1244:
1241:
1225:
1222:
1219:
1216:
1213:
1198:
1192:
1186:
1183:
1180:
1173:
1169:
1159:
1154:
1143:
1135:
1134:
1126:
1110:
1099:
1064:
1054:
1051:
1046:
1037:
1017:
1008:
997:
990:
977:
968:
957:
950:
946:
922:
909:
908:
905:
904:
903:
876:
866:
863:
858:
850:
833:
811:
798:
797:
794:
793:
792:
790:
774:
751:
743:
727:
687:
683:
677:
670:
657:
653:
643:
640:
630:
629:
626:
625:
624:
622:
618:
604:
600:
598:
557:
548:
540:
531:
528:
512:
503:
495:
494:
491:
490:
489:
474:
458:
449:
446:
430:
421:
418:
399:
369:
360:
351:
350:
347:
346:
345:
336:
334:
323:
320:
316:
312:
308:
304:
293:
283:
269:
267:
256:
253:
250:
239:
236:
232:
228:
226:
221:
217:
214:
205:
201:
197:
193:
189:
185:
181:
177:
173:
169:
165:
161:
157:
153:
149:
145:
141:
139:Power density
137:
133:
129:
126:0.6-10.0 A/cm
125:
121:
117:
113:
109:
105:
100:
96:
92:
88:
84:
80:
76:
72:
68:
62:
58:
55:Solid polymer
54:
50:
46:
42:
37:
30:
25:
20:
2556:Electrolysis
2532:. Retrieved
2528:
2516:
2504:. Retrieved
2499:
2487:
2475:. Retrieved
2463:
2451:
2443:
2426:
2414:. Retrieved
2410:bellona.org/
2409:
2396:
2383:
2373:
2356:
2350:
2315:. Weinheim:
2312:
2306:
2289:
2285:
2279:
2246:
2242:
2229:
2196:
2192:
2182:
2160:(10): 1674.
2157:
2153:
2147:
2138:
2132:
2121:. Retrieved
2117:
2108:
2065:
2061:
2051:
2040:. Retrieved
2033:the original
2020:
2009:
1982:
1978:
1968:
1951:
1947:
1846:Electrolysis
1793:
1789:
1780:
1763:
1754:
1734:
1676:
1621:electrolysis
1618:
1615:Ohmic losses
1589:cell voltage
1570:
1471:Ohmic losses
1460:
1268:
1089:
901:
716:
614:
593:
486:
352:
342:
329:
299:
270:
262:
254:
245:
231:Electrolysis
229:
215:
212:
211:
190:<20,000 h
131:Cell voltage
1856:Gas cracker
1591:at a given
1024:electricity
615:As per the
198:<14 μV/h
142:to 4.4 W/cm
134:1.75-2.20 V
2550:Categories
2123:2023-04-30
2042:2014-12-03
1898:References
1463:fuel cells
301:localized
259:Advantages
118:<30 bar
2317:Wiley-VCH
2221:0378-7753
2199:: 56–65.
2100:141506732
2092:2589-2991
2001:104308293
1737:Ohm's law
1713:⋅
1700:∝
1655:⋅
1625:Ohm's law
1404:×
1371:⋅
1353:Δ
1217:×
1184:⋅
1166:Δ
1018:⏞
978:⏟
843:⟶
837:Δ
772:Δ
725:Δ
688:⏟
681:Δ
658:⏟
651:Δ
638:Δ
546:⟶
541:−
459:−
392:⟶
326:Reactions
2534:17 April
2506:17 April
2477:17 April
2468:Archived
2416:22 April
2388:Archived
2271:14851298
1799:See also
1577:hydrogen
947:→
621:enthalpy
319:enthalpy
268:output.
89:Titanium
81:Platinum
2251:Bibcode
2201:Bibcode
2162:Bibcode
2070:Bibcode
789:entropy
740:is the
296:Science
242:History
218:is the
206:10-20 y
182:30 Nm/h
110:50-80°C
73:Iridium
2323:
2269:
2219:
2098:
2090:
1999:
1581:oxygen
1416:
1394:kJ/mol
1389:
1269:where
1229:
1207:kJ/mol
1202:
1001:
961:
717:Where
174:57-69%
2525:(PDF)
2496:(PDF)
2471:(PDF)
2460:(PDF)
2436:(PDF)
2406:(PDF)
2267:S2CID
2239:(PDF)
2096:S2CID
2036:(PDF)
2029:(PDF)
1997:S2CID
1534:trans
1421:C/mol
1386:285.9
1234:C/mol
998:237.2
665:elec.
282:mol-%
150:0-10%
2536:2018
2508:2018
2479:2018
2418:2018
2321:ISBN
2217:ISSN
2088:ISSN
1579:and
1498:cell
1432:1.48
1245:1.23
984:heat
958:48.6
695:heat
619:the
317:the
288:in O
276:in O
2440:RWE
2361:doi
2294:doi
2259:doi
2247:149
2209:doi
2197:309
2170:doi
2158:126
2118:IEA
2078:doi
1987:doi
1956:doi
1745:PEM
1549:ohm
1519:act
1413:485
1309:is
1226:485
1199:237
1149:rev
1105:rev
1013:mol
973:mol
227:.
2552::
2527:.
2498:.
2466:.
2462:.
2438:.
2408:.
2386:.
2382:.
2357:38
2355:.
2335:^
2319:.
2290:27
2288:.
2265:.
2257:.
2245:.
2241:.
2215:.
2207:.
2195:.
2191:.
2168:.
2156:.
2116:.
2094:.
2086:.
2076:.
2064:.
2060:.
1995:.
1983:44
1981:.
1977:.
1952:38
1950:.
1906:^
1603:.
1473:,
1407:96
1336:th
1317:.
1220:96
1005:kJ
965:kJ
522:aq
440:aq
292:.
2538:.
2510:.
2481:.
2420:.
2367:.
2363::
2329:.
2300:.
2296::
2273:.
2261::
2253::
2223:.
2211::
2203::
2176:.
2172::
2164::
2141:.
2126:.
2102:.
2080::
2072::
2066:2
2045:.
2003:.
1989::
1962:.
1958::
1716:R
1708:2
1704:I
1697:Q
1658:R
1652:I
1649:=
1646:V
1544:V
1540:+
1529:V
1525:+
1514:V
1510:+
1507:E
1504:=
1493:V
1437:V
1429:=
1410:,
1401:2
1380:=
1374:F
1368:n
1361:0
1357:H
1347:=
1342:0
1331:V
1297:F
1277:n
1250:V
1242:=
1223:,
1214:2
1193:=
1187:F
1181:n
1174:0
1170:G
1160:=
1155:0
1144:V
1111:0
1100:V
1065:2
1061:O
1055:2
1052:1
1047:+
1038:2
1034:H
1009:/
991:+
969:/
951:+
941:)
938:l
935:(
931:O
923:2
919:H
877:2
873:O
867:2
864:1
859:+
851:2
847:H
840:H
834:+
830:)
827:l
824:(
820:O
812:2
808:H
775:S
752:T
728:G
684:S
678:T
671:+
654:G
644:=
641:H
573:)
570:g
567:(
558:2
554:H
549:2
537:e
532:4
529:+
525:)
519:(
513:+
509:H
504:4
455:e
450:4
447:+
443:)
437:(
431:+
427:H
422:4
419:+
415:)
412:g
409:(
400:2
396:O
388:)
385:l
382:(
378:O
370:2
366:H
361:2
290:2
286:2
284:H
278:2
274:2
272:H
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.