Development of Hybrid Electric Vehicles in Austral

1DevelopmentofHybridElectricVehiclesinAustraliaH.C.Lovatt,aD.A.J.Rand,bandA.M.VassallocaCSIROTelecommunicationsandIndustrialPhysics,Epping,NSW2070(Australia)bCSIROEnergyTechnology,ClaytonSouth,Victoria3169(Australia)cCSIROEnergyTechnology,NorthRyde,NSW2113(Australia)1.TowardssustainableroadtransportationWorld-wide,majorautomotivemanufacturersareshowingconsiderableinterestinthedevelopmentofhybridelectricvehicles(HEVs).Thesevehiclesmaybeheat-engine-batteryhybrids,orall-electricdesignswithafuelcelltoproviderangeandahigh-powerbatterytoboostacceleration.Todate,theToyotaPriusandHondaInsight,whicharebothinternalcombustionengine(gasoline)-battery(nickel-metal-hydride)hybrids,haveattractedthemostattention.Already,salesofthePriushavereached60000.Meanwhile,DaimlerChrysler,FordandGeneralMotorsintendtointroducehybridlighttrucksintheUSAin2003-04.Thesefivecompanies,aswellasNissan,RenaultandVolkswagen,arealsodemonstratingprototypefuel-cell-batteryhybrids[1].Whyareautomotivemanufacturersinterestedinhybridcars?Theanswerliesinalleviatingenvironmentalconcernsintermsofreductionsinbothurbanpollutionandgreenhousegasemissions,andinincreasingfuelefficiency.InAustralia,forexample,roadtransportationcausesbetween70and90%ofurbanairpollutionandcontributesapproximately17%oftotalgreenhousegasemissions.AnHEVwithanadvancedgasolineengineistechnologicallyandeconomicallyfeasibletodayandcanreducegreenhousegasemissionsbyuptotwo-thirds,andotheremissionsbyupto90%,whenmeasuredagainsttheperformanceofpresentautomobilesofsimilarsizeandperformance.2WhencomparingtheemissionsandtheefficienciesofthedifferentpowersourcesthatcouldbeusedinHEVapplications,itshouldberememberedthattheonlymeaningfuldataarethosewherethefull'well-to-wheels'processisconsidered,namely:extractionofresource(naturalgas,coaloroil);fuelproduction;transportationandlocaldistribution;refuelling;anyfurtheron-boardprocessingoffuel;engine,batteryorfuel-stackefficiency;anyotherenergylossespriortodeliveryofpowertothewheels.Inthisrespect,novehiclecanbeconsideredtobetruly'zeroemission',evenwhenpoweredbyfuelswhichoperateonpurehydrogen.1.1.Pure-batteryelectricvehiclesFollowingthe'energycrises'ofthe1970s,mucheffortwasdevotedtotheadvancementofbattery-operatedelectricvehicles(EVs).Inmorerecenttimes,theinitiativeforEVshasstemmedlargelyfromCalifornianlegislationonenvironmentalpollutionwhichwasintroducedinDecember1989.Undertheregulations,thelargestautomobilemanufacturers(DaimlerChrysler,Ford,GeneralMotors,Honda,Nissan,Toyota)wererequiredtoproducezero-emissionvehicles(ZEVs).Inmodelyears1998through2000,2%ofallnewvehiclesofferedforsaleinCaliforniabythesemanufacturersweretobeZEVs,andthispercentagewastoincreaseto5%inmodelyears2001and2002,and10%inmodelyear2003andbeyond.In1996,theregulationsweremodifiedtoallowadditionaltimeforthetechnologytodevelop.Therequirementfor10%ZEVsinmodelyear2003andbeyondwasmaintained,butthesalesrequirementformodelyears1998through2002waseliminated.Overtheyears,manydifferenttypesofbatteryhavebeeninvestigatedaspowersourcesforEVs[2].Thesehaveincludedlead-acid,aluminium-air,nickel-zinc,sodium-sulfur,zinc-airandzinc-halogensystems.IntheUSA,aconsortiumofautomotivecompanies,inpartnershipwiththegovernment,setuptheUnitedStatesAdvancedBatteryConsortium(USABC)withthegoalofdevelopingahigh-performancebatterysuitablefortraction3purposes.Thisresultedinsubstantialresearchanddevelopmentprogrammesonnickel-metal-hydride(Ni-MH),lithium-ionandlithium-polymerbatterieswiththetargetofproducingfull-sizeEVbatteriesfordemonstrationpurposes.Unfortunately,despiteintensiveresearchworld-wide,eachoftheabovementionedbatterysystemsstillsuffersfromoneormoreoftheage-oldproblemsoflowspecificenergy(whichrestrictsthedrivingrangeofEVs),inadequatereliability,longrechargingtime,limitedservicelife,excessiveweight,andhighcost.Consequently,EVshavenotmetwithgreatcommercialsuccess.ByMay2000,only2300EVshadbeenintroducedundertheCalifornianZEVprogramme(Table1).Lastyear,evenGeneralMotorsdecidedtoceaseproductionofitsmuch-publicizedEV1withfewerthan700ontheroad.Today,thebattery-poweredEVdoesnotappeartoposeanythreattothesupremacyoftheinternal-combustion-enginedvehicle(ICEV).Fromtheseexperiences,EVdevelopersshouldconcludethatthecustomerwillonlychangetoanewtechnologyifitissignificantlybetterthanthatwhichitseekstoreplace.Table1.ElectricvehiclesdeployedinCalifornianZEVprogramme(toMay2000).ManufacturerModelNumberBatterytypeCityrangea(km)Highwayrangeb(km)DaimlerChryslerEPIC17Lead-acid113105EPIC93Ni-MH148156FordRanger52Lead-acid135111Ranger327Ni-MH151138GeneralMotorsEV1606Lead-acid121126EV1162Ni-MH230245S-10110Lead-acid7469S-10117Ni-MH148159HondaEVPlus276Ni-MH201169NissanAltra81Li-ion193172ToyotaRAV4486Ni-MH229187aUSurbandynamometerdrivingschedule.bUShighwayfueleconomydrivingschedule.41.2.Fuel-cellvehiclesInparallelwithresearchintoadvancedbatteries,othercompaniesstartedworkingonfuelcells.Thisdevicewasinventedin1839bySirWilliamGroveandbytheturnofthe19thcentury,renownedscientistssuchasWilhelmOstwaldwerepredictingthereplacementofheatenginesbyfuelcells