Fuel cell_types,working,applications

Fuel cell full description,history,types,applications with references.

2. TownshipCampus,Lahore
Submittedto:Dr.M.Iqbal
Submittedby:MuhammadKashifHanif
(mcf1700986)
Programme:M.ScChemistry(E)
SemesterI
Subject: Quantumchemistry
Coursecode:CHEM3113

3. Contents:
.Introduction
.Whytousefuelcells?
.Comparedtobattery
.Construction
.Working
.Typesoffuelcell
.Applications
.Advantages
.Disadvantages
.References
“FUELCELLSTECHNOL0GY”
Introduction:
Fuelcellsareelectrochemicaldevicesthatconvertchemical
energyoffuels(usuallyhydrogenderivedfromnaturalgasor
biogas)intoelectricalenergy,promisingpowergenerationwith
highefficiencyandlowenvironmentalimpact.
Thefirstfuelcellswereinventedin1838byWilliamRobert
Groove
[1].
Combustionisavoidedinthesecellsso,fuelcells
producepowerwithminimalpollutants.Theycanvaryfromtiny
devicesproducingonlyafewwattsofelectricitylikeinphones
and
laptopsrightuptolargepowerplantsproducingseveralmega-watts.

4. Whytousefuelcells?
Theconventialenergysourceslikecoal,petroleumand
dieseletcthatweareusingtodayproducemuchamountofco2
whichismajorgreenhousegasthatisresponsibleforglobalwarming
causingmuchthreatsbothforenvironmentandotherorganisms.Sea
levelhaverisenabout7inchesintheprevious100yearswhichis
morethanprevious2000years.
[2]
.
AndaccordingtoUNIPCC(InternationalPanalClimateChange)
report2007sealevelwillrisefrom7-23inchesattheendofthis
centuryduetoglobalwarming
[3]
.Thus
contributinglottoairpollution,alsotheseresourcearelimitedanditis
muchfearthattheywillbedepletedinnearfuture.About100Million
Barrelofoilisuseddaily(1barrel=About159Liters).Accordingtothis
rate,itisfearthattheywillbedepletedinnext900years
[4]
.So,wehave
tofindsuchwaysofenergyproductionthataremoreefficientand
environmentfriendly.Oneofthesearefuelcells.Theydonotpollutethe
environmentinanywayastheby-productthatisproducedisclean
waterandheat.More-ever,Theycanbepractically60%efficientas
comparedtocarfuelwhichisabout25%efficientwhiletheir
theoreticalefficiencycouldbeupto80%approximately.

5. POSCO;Fuelcellpowerplantin Airpollutionthroughotherresources.
Vs
SouthKorya.
Comparedtobattery:
Abatteryusesclosedstoreofenergywithinitandoncethisis
depletedthebatterymustbediscardedorrechargerdbyusingan
externalsupplyofelectricity.Whileafuelcell,ontheotherhand,usesan
externalsupplyofchemicalenergyandcanrunindefinitelyaslongasit
issuppliedwithsourceofhydrogenandasourceofoxygen(usually
air).Generallythesourceofhydrogenisreferredasfuelandthisgives
thefuelcellitsname.

6. .
Working:
Fuelcellscomeindifferentvarietiesbuttheyallworkonsame
generalprincile.Theyareallmadeupofthreeadjacentsegments;
theanode,theelectrolyteandthecathode.Twochemicalreactions
occurattheinterfacesofthethreedifferentsegments.Thenetresultof
thetworeactionsisthatthefuelisconsumed,waterisproduced,and
anelectriccurrentisgenerated,whichcanbeusedtopowerelectrical
devices,normallyreferredastheload.
Attheanodeacatalystoxidizesthefuel(i.ehydrogen)turningthe
fuelintoapositivelychargedionandnegativelycharged
electron.Theelectrolyteisasubstancespecificallydesignedsoions
canpassthroughiteasilybuttheelectronscannot.Thefreed
electronstravelthroughawirecreatingtheelectriccurrent.Theions
travelthroughtheelectrolytetothecathode.Oncereachingthe
cathode;theionsarereunitedwiththeelectronsandthetworeactwith
thirdchemicalusuallyoxygentocreatewater
[1]
.

7. Atypicalfuelcellproducesavoltagefrom0.6Vto0.7Vatfullrated
load.Theyarearrangedinseriesintheformofstackstoproducemore
amountofenergy
[5]
.
Construction:
Afuelcellmainlyconsistsoffollowingcomponents.
.Theelectrolytesubstance.Theelectrolytesubstanceusually
definesthetypeoffuelcell.
.Thefuelthatisused,themostcommonfuelusedis
hydrogen.
.Theanodecatalystbreaksdownthefuelintoelectronsand
ions.Theanodecatalystismadeupofveryfineplatiniumpowder.
.Thecathodecatalystturnstheionsintotheproductslikewater
orcarbondioxide.Thecathodecatalystismadeupofplatiniumor
platinium-groupmetalsanditcanalsobemadeofnon-platinium
metalssuchasiron
[1]
.

8. Typesoffuelcells
[6]
:
Althoughtherearemanytypesoffuelcellstodaysusedindifferentfields
oflife,butsixmainandmostusedtypesarebeingdiscussedhere:
.Protonexchangemembranefuelcell(PEMFC)
.Alkalinefuelcell(AFC)
.Phosphoricacidfuelcell(PAFC)
.Moltencarbonatefuelcell(MCFC)
.Solidoxidefuelcell(SOFC)
.Directmethanolfuelcell(DMFC)

9. 1.PEMFC:
Thesearealsoknownaspolymerelctrolytemembranefuel
cells.
ThePEMfuelcellwasinventedintheearly1960byW.T
GrubbandL.Niedrachofgeneralelectricity.
InPEMFC theelectrolyteusedisathinpolymer
membranesuchasperfluorosulphonicacid.
Hydrogenflowsintothefuelcellontotheanodeandsplitsinto
hydrogenionsandelectrons.
Hydrogenionspermeateacrosstheelectrolytetothe
cathode.
Electronsflowthroughanexternalcircuitandsupplypower.
Oxygenissuppliedtothecathodeandthiscombineswith
electronsandhydroegnionstoformwater.
Theyoperateatatemperatureofabout80
0
C.
Electrolyteispresentbetweenthetwofieldflowplates.
Eachcellproducesabout0.7Vabout,enoughpowertolighta
bulb.
Theycanbeusedinvehicles,motorbikes,portablepowersof
electricity,APUs(auxiliarypowerunits),onsmallerscale
stationaryelectricitygeneration.

10. 2.AlkalineFuelcells(AFC):
InventedbyFrancisThomasBaconin1959.
ElectrolyteusedforthisdeviceisaquoussolutionofKOHor
NaOHsolution.
CompressedH2andO2fuelisused.
Approximately70%efficiency.
Operatingtemp.isaround150
0
Cto200
0
C
300Wto5kWoutputrequirespurehydrogenfueland
platiniumcatalyst
UsedonNASAshuttlesthroughoutthespaceprogramme.

11. 3.Phosphoricacidfuelcell(PAFC):
Introducedin1961byG.VElmore&H.ATanner
H
+
movefromanodetocathode
Moltenphosphoricacid(H3PO3)isusedasanelectrolyte
Operatingtemperatureabout150to200
0
C
Efficiencyupto55%butcanbeenhanceupto80%
11MVunitshavebeentested
Sulphurfreegasolinecanbeusedasfuel
Canbeusedoncommercialscale
=>Disadvantages:
Electrolyteisverycorrosive
Platiniumcatalystisveryexpensive

12. 4.MoltenCarbonateFuelcell(MCFC)
[7]
:
Moltenalkalinecarbonatesuchaslithiumpotassium
carbonateisusedasaneletrolyte
InthisfuelcellCO3
2-ions
movefromcathodetoanode
Producepowerupto100MW
Canbeusedashighpowergenerators
Canbeoperatedathightemperatureupto650
0
C
TheirNickelcatalystarenotsoexpensiveandhencecanbe
usedoncommersialscale
Efficiencyupto55%
=>Disadvantages:
Shorterlifespane
Slowstartuptime
Corrosionofelectrodes

13. 5.SolidOxideFuelCell(SOFC):
Hardceramiccompoundofmetaloxidesuchascalcium
oxideorzirconiumoxideisusedasanelectrolyte
O
2-
movefromcathodetoanode
Operatingtemperaturerangefrom800to1000
0
C
Popularinstationarypowergeneration
Slowstartuptime
Cellsoutputisabout100kW.

14. 6.DirectmethanolfuelCell(DMFC):
Polymermembraneisusedasanelectrolyte
Useaplatinium-rutheniumcatalystontheanodeanda
platiniumcatalystonthecathode.
Thiscatalystcanwithdrawhydrogenatomsfromliquid
methanol,whichisusedasfuelinsteadofhydrogen,giving
thecellitsname.
Operateintherangefrom60
0
Cto130
0
.
Theyareconvenientforportablepowerapplicationswith
outputsgenerallylessthan250W.

15. ApplicationsofFuelCells
[1]
:
Canbeusedaspowersourcesinremoteareas
Canbeusedtoprovideoff-gridpowersupplies
Canbeapplicableinbothhybridandelectricvehicles
Wastewatertreatmentplantandlandfill
Canbeusedincellularphones,laptopsandcomputers
Canbeusedinhospitals,creditcardcentersandpolice
stations
Inbuses(inaugust2011therewereonly100FCbusesin
entireworld)
[1]
,cars(likeToyotamirai,MercedesBenz,Honda
FCX,AudicompanyFCVandBMWFCV)
[1]
,planesFirsttest
flightwasdoneinFeb2008inEurope),boats(namedasHydra
generatingabout6.5kWnetoutput)
[1],
forklifts(in2013,4000
werepresentinUS)
[1]
andtrains,andsubmarines(likeType212
submarinesoftheGermanandItaliannavies)
Asvacuumcleaners
Intelecommunicationsandmp3playersetc

16. AdvantagesofFuelCells
[8]
:
Onlycleanwaterisdischarged
Higherefficiencythanconventialengines
Zeroemissionandcombustion
Longoperatedperiodbetweenfailure
Norotatingpartsinthemainhardwarecomponents
·Negligiblenoisepollution
Fuelcellsforlaptop Fuelcellrechagers

17. BoeingcompanyFCP AFCVbus
Hydra;FuelcellboatFuelcellforklift
ToyotaFCVCar
DisadvantagesoffuelCells:
Purehydrogenisdifficulttohandleandstoreasitisvery
inflammable
Onlylittlehigherefficiencythanotherresources
Theyareveryexpensive,thepriceofstationaryfuellcellhasdroped
from$600000perkW(whenfuelcellwasbeingusedbyNASA)to
$4500today
[9]
.
Fuelcellsmartphone

18. References:
1.Wikipedia.org/Fuelcells
2.https://climate.nasa.gov/evidence/
3.https://climate.nasa.gov/evidence/
4.https://www.quora.com/When-is-the-earth-supposed-to-run-
out-of-oil
5.Nice,Karim,StriclandandJonathan“Howfuelcells
work”.Howstuffworks,accessedin4august2011.
6.Fuelcellhandbook(seventhedition)byEG&G
technicalservices,Inc,innovember2004
7.Moltencarbonatefuelcelltechnology.U.S
Departmentofenergy,9august2011
8.https://google.com/Fuelcellsslideshare
9.Fuelcells.briefingpapersforstatepolicymakerspublishedin
august2011byCESA(CleanEnergyStatesAlliance)