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cleanerexhaustemissions isgrowing in lightof risingfossil fuelpricesandenvironmentalproblemssuchasair pollution andglobalwarming. Automakershavebeenworkingtoexpandthenumberofvehiclemodelsequippedwithhybridsystemsasonewayofaddress-ingthisdemand.Japanesemanufacturershavefocusedon fuel-efficienthybridelectricvehicles (HEVs),whichcombinean internalcombustionenginewithanelectricmotor. Section1of thisarticledescribesthetrends inHEVsthatoccurredin2014.1. 2. Popularization of HEVs in JapanFigure1showsthatthenumberofHEVsontheroads
inJapan is increasingyearafteryear. Thenumberofhybridpassengervehicleshassignificantlyexceededthe3millionvehiclemarkandisquicklyapproaching4mil-lionvehicles.In2013,thenumberofHEVsontheroadinJapanincreasedbynearly1millionvehiclescomparedtothepreviousyear. Thenumberof trucksandothernon-passengerhybridvehiclesisalsoexpandingsteadily.Thenumberofplug-inHEVs(PHEVs)isalsoincreasingandthereareapproximately30,000on theroad. Thisnumbershouldcontinuetoexpandinthefutureasauto-makerscontinuetoincreasetheavailabilityofPHEVs.1. 3. New HEVs that launched in Japan in 2014Table 1 lists the hybrid passenger vehicles that
InJuly,ToyotaMotorCorporationaddedafour-wheeldriveversionof theCrownMajesta. This is the firstfull-timefour-wheeldriveHEVfromToyota.Theorigi-nalhybridsystem in the two-wheeldrivevehiclewasequippedwitha3.5-literV6engineandthetotalsystemoutputwas252kW. Inthisnewfour-wheeldrivever-sion, a 2.5-liter inline four-cylinderenginewasadded,creatingatotalsystemoutputof162kW.Thefuelecon-omyis19.0km/L(undertheJC08testcycle).
On the sameday in July,ToyotaMotorCorpora-tionalsoaddeda four-wheeldriveversionto itshybridCrownmodel. Thehybridsystem is thesameas theoneintheCrownMajesta.Itisequippedwitha2.5-literinlinefour-cylinderenginewithatotalsystemoutputof162kW.Thefueleconomyis21.0km/L(undertheJC08testcycle).
AlsoinJuly,LexuslaunchedtheNX300h.Thehybridsystem in the four-wheeldriveversion is almost thesameasthatintheToyotaHarrier.Itisequippedwitha2.5-literinlinefour-cylinderengine,a105kWmotoronthefrontaxleanda50kWmotorontherearaxle.This
Hybrid Vehicles, Electric Vehicles, Fuel Cell Electric Vehicles
Fig. 1 Trends in the number of HEVs on the road in Japan (1)
makesthetotalsystemoutput145kW.Inthetwo-wheeldriveversion, thehybridsystemconsistsofa2.5-literinline four-cylinderengineanda105kWmotoronthefront axle, creatinga total systemoutput of 145kW.Thefueleconomyis19.8km/Lforthefour-wheeldriveversionand21.0km/Lfor thetwo-wheeldriveversion(undertheJC08testcycle).
InAugust, SuzukiMotorCorporation launched the
hybridWagonR. This is the first time thatahybridsystemhasbeenequippedonaminivehiclewith the“tallwagon”design(i.e.,amini-vehiclewithaheightof1.55metersormore). Thehybridsystemisaso-calledmildhybridthat isequippedwithan integratedstartergenerator(ISG).TheISGusestheenergyfromdecelera-tion (braking) tocharge thevehicle's leadand lithium-ionbatteriesandthenthiselectricalpower isused for
Table 1 Main hybrid passenger vehicles launched in Japan in 2014(2)─(6)
In the samemonthToyotaMotorCorporationalsolaunchedtheEsquire.ThehybridsystemisalmostthesameasthatintheNoahandVoxythatwerelaunchedinJanuary.TheEsquire isequippedwitha1.8-liter in-line four-cylinderengineandthetotalsystemoutput is100kW.Thefueleconomyis23.8km/L(undertheJC08testcycle).
InNovember,HondaMotorCompanylaunchedthehy-bridLegend.Thisvehicle isequippedwiththeworld'sfirstthree-motorhybridsystem,asshowninFig.2.Po-sitionedatthefrontofthevehicleareanewlydevelopedV63.5-literdirect-injectionengineanda7-speeddual-clutchtransmission(DCT)withanintegratedelectricmo-tor.Therear-mountedtwinmotorunit(TMU)containstwomotors thatdistribute torque to the rearwheels.This hybrid system features three distinct drivingmodeswherethehybridsystemautomaticallycontrolstheengineand threemotors foroptimalperformance.InEVdrive,thetworearelectricmotorspowertheve-hicle. Inhybriddrive, thegasolineenginepowers thefrontwheelswhilethetworearmotorspowertherearwheels. Inenginedrive, thegasolineengineprovidespowertothefrontwheels.Thehybridsystemautomati-
inrecentyearsas thenextgenerationofenvironmen-tallyfriendlymobilitywithexcellentenvironmentalper-formanceandenergyefficiency. Despitethis, themainissuesholdingbackEVs, suchasbatteryperformance(cruisingrange, charging time), cost, and theavailablecharging infrastructure,haveyettoberesolved. How-ever,technologicaldevelopmentstoimprovebatteryper-formanceandreducethecostofEVshavebeenmakingsteadyprogress. Front-runners intheEVfieldsuchasNissanandMitsubishiMotorsCo.,Ltd.haveexpandedthenumberofEVmodelstomeetavarietyofdifferentneedsanduses,whilealsoreducingprice. Inaddition,theJapanesegovernmenthasactivelyworkedtofurtherpromotetheintroductionofEVsintothemarketbyex-pandingtheavailablecharginginfrastructure,aswellasbyencouragingtechnologicaldevelopmentandlaunchingbudgetaryand taxmeasures to improveperformanceand reducecost. Asa result, thepopularizationandadoptionofEVshasstarted togainmoremomentum.Section2of thisarticledescribes thecurrent stateofEVuseinJapan,theinitiativestakenin2014tofurtherexpandtheusageofEVs,andthetrendsinstandardiza-tion. Section4of thisarticlewillprovidemoredetailsaboutthebatterycharginginfrastructureinJapan.2. 2. Popularization of EVs2. 2. 1. Market introduction and sales
Figure3shows thenumberofEVson theroads inJapan,excludingmotor-drivencyclesandmini-vehicles(7).ThenumberofsuchvehiclesinJapanhasincreasedsince2009whenMitsubishiMotorsandFujiHeavyIn-dustriesbegansalesof twosmallEVs, the i-MiEVandtheSubaruplug-inStella, respectively. By theendof2013thenumberofEVshadreached54,757vehicles(thegreatmajorityof thesearemini-vehiclesandpassengervehicles, thenumberof trucksandotherEVshashov-eredaroundseveraldozenvehicles).Table2showsthespecificationsof themainEVs launched inJapan from2009to2013 (8)-(14). InthecaseofpassengerEVs, theNissanMotorCo.,Ltd.begangeneral salesof itsNis-sanLeaf in2010,whileMercedes-Benzbeganselling itssmartfortwoelectricdrivemodelin2012.Alsoin2012,Honda,MazdaMotorCorporation, andToyotabeganleasingtheFitEV,DemioEV,andeQ,respectively.By2013Mitsubishihadestablisheddifferentgrades forthei-MiEVdepending on the cruising range on a singlecharge(thetopmodelfeaturedanextendedrangeonasinglecharge). The lineupof i-MiEVmini-vehiclesalsofeaturedcommercialmodelssuchas theMinicab-MiEVVan(2011)andtheMinicab-MiEVTruck(2013).Mitsubi-shirevisedthepricesofalloftheseEVsinanefforttohelplowerthepricesofotherEVsinJapan.Nissanalsoworkedtoextendthecruisingrangeonasinglechargeof itsLeafEVandrevised itspricingtohelp lowerthesalespricesofotherEVsinJapan.
Table 3 shows the specifications of themainEVslaunchedinJapanin2014(10)(15)(16).InApril,BMWbe-gansellingthei3.Thissamevehicleisalsoofferedwiththeoptionofarangeextender(anengineforgeneratingelectricity) that isexpectedtohelpextendthecruisingrange.
Fig. 3 Trends in number of EVs in use in Japan (7)
Consequently,itisclearthatthenumberofEVmodelsthatJapaneseconsumerscanchoosefromhasonlybeenincreasingsince2009andthatthevarietyvehiclemodelshasbeenexpandingsteadilytomeetdifferentneedsanduses.2. 3. Initiatives to expand EV popularization2. 3. 1. Adoption of EV buses, trucks, and taxisThe JapaneseMinistryofLand, Infrastructureand
Transport (MLIT) is looking to effectively acceleratethepopularizationandadoptionofelectricvehicleswithparticularlygoodenvironmentalperformance (includingPHEVs).Electricbuses,taxis,andtrucksarebeingusedtopromotemoreenvironmentally friendlyregionsandtransportation-relatedbusinessesandalso topromotelow-carbonurbandevelopment. To thisend,MLIT iscarryingoutaprojecttomakeregionalandtransporta-tionbusinessesmoreenvironmentallyfriendlyasawaytoinducetheadoptionofEVsbyotherregionsandbusi-nesses (18). Thisprojectprovides targetedsupport tospecificautomobileandtransportationbusinesses(limitedtobus, taxi,or truckbusinesses) thathavebeen identi-fiedaspioneerstohelpencouragetherapidpopulariza-
tionofEVs.Everyyearnumerouspotentialtargetsforsupportareselectedandthecreationofwell-conceivedinitiativesisexpectedtohelppopularizetheadoptionofEVsallacrossJapan.2. 3. 2. Adoption of ultra-compact vehiclesInrecentyears,ultra-compactvehicles thatareeven
smaller thanmini-vehicleshavebeenattractingan in-creasingamountofattention.TheguidelinesdevelopedbyMLITtohelppromotetheuseoftheseultra-compactvehiclesdefinetheseasvehiclesthataremorecompact,maneuverable, andenvironmentally friendly thancon-ventional automobiles, and that cancarryoneor twopeopleonshortlocaltrips.MLIThasintroducedrelaxedstandardsbasedontheSafetyRegulationsforRoadVe-hiclesundertheRoadTruckingVehicleLawasawayofensuringthesafetyofultra-compactvehicles. Thesestandardsprohibit thedrivingofultra-compactvehiclesonexpressways, restrictusage to locationscapableofensuringsafeandsmoothtrafficflows,andapplycondi-tions forsizeandperformance. Thisrelaxingofsomeregulationsisallowedonlyinthecaseswherethesafetyandenvironmentalperformanceof thesevehicles isnotadverselyaffected. Thesestandards (theultra-compactvehiclecertificationsystem)wereestablishedinJanuary2013andallowultra-compactvehicles tobedrivenonpublicroadsinJapan(18).
Table 3 Specifi cations of main EVs launched in Japan in 2014(10)(15)(16)
Since thedefinitionof theseultra-compactvehiclesclearlystatesthatexcellentenvironmentalperformanceis required,mostof thesevehiclesareEVs. Thishasraisedexpectations thatvehiclessuchas thesewillbeable tomakeamajorcontribution toa transportationsystemthatusessignificantlylessenergyandemitsfarlesscarbon.Combiningthesevehicleswithurbanplan-ningmayhelptoimprovequalityoflifeandmobilityasanew formofurbanand local transportation. Thesevehiclesmayevenhavemanyotherpositivesocialben-efits,suchasprovidingaboost totourismandregionalregeneration,aswellassupporting themobilityof theelderlyandchild-raising families. Consequently, localgovernmentsare leadingtrial introductionsof theseul-tra-compactvehiclesandtrialdemonstrationsarebeingcarriedout inconjunctionwithurbanplanningprojectsallacrossJapan.Table4showsthespecificationsofthemainultra-compactvehicles(10)(12)(14)(20).2. 4. Trends in EV standardizationSection1.4explainedhowthe internationalstandard-
ization of electric vehicles is beinghandledby ISO/TC22/SC37. ThesafetyaspectsofEVsarebeingad-dressed in ISO6469-1 to ISO6469-4 (seeSection1.4).The international standards that concern theperfor-manceaspectsofEVs include ISO8714 (Referenceen-ergyconsumptionandrangeforBEV),whichwasissuedin2002,andISO8715(RoadoperatingcharacteristicsforBEV),whichwasissuedin2001.
researchanddevelopmentofFCVs, startingwith theMirai,andthetrendssurroundingtheestablishmentofhydrogenfuelstationsinJapan.3. 2. Trends in FCV research and developmentTherewerenewsreleasesaboutFCVs fromtwoof
OnAugust29,2014Toyotaannouncedthatithadob-tainedtheapprovaloftheJapaneseMinistryofEconomy,TradeandIndustry (METI)asa“registeredcontainermanufacturer” for its high-pressure hydrogen fueltanks(26).Allcontainersandaccessoriesforstoringgasat1MPa (10atm)ormoreofpressure,suchasahigh-pressurehydrogen fuel tank,mustbetype-certifiedbyMETI. Inaddition, theHighPressureGasSafetyLawin Japan requires that thismanufacturingprocessbemadeavailableforofficialsafetyinspectionsbytheHighPressureGasSafetyInstituteofJapan.NowthatToyotahasobtainedthisapproval,itisallowedtoself-inspectitsownhigh-pressurehydrogenfueltanks,whichisexpect-edincreasemanufacturingefficiencyandproductivity.
OnNovember17,2014Hondaunveiledboth itsnew-modelFCVconcept car, called theHondaFCVCON-CEPT(Fig.5),andalsotheconceptmodelofitsportableinverterbox, called theHondaPowerExporterCON-CEPT(Fig.6),whichcanprovideanexternalsupplyofelectricityfromaFCVatamaximumoutputof9kW(25).
hydrogen that is transported to the stationon trucksfrom liquidhydrogenproductionbases. Thehydrogenfuelsupplycapacity is6vehiclesperhour (340Nm3/h),thepressureoftheliquidhydrogenduringrefuelingis70MPa,and it takesabout3minutespervehicletofinishrefueling.OnAugust28,2014Iwatanialsoannouncedaplantobuildhydrogenrefuelingstations incentralTo-kyo,theplacewheredemandforahydrogenfuelsupplyismostdesired(28).Inaddition,IwataniCorporationhascommitteditselftobuilding20commercialhydrogenfuelstations inthe fourmajormetropolitanareasofTokyo,Nagoya,Osaka,andFukuokaby2015.Clearly,progressisbeingmadeinpreparationstoestablishasolidfounda-tionforahydrogenfuelsupplyinfrastructureforFCVs.
OnNovember14, 2014 Iwatani announced that thepriceofhydrogenfuelwouldbe1,100yen/kg(100yen/Nm3) (29). Thisprice isequivalent to the fuelcost forhybridvehicles. Accordingto theHydrogenandFuelCellStrategyRoadmap (30)compiledbyMETI,thetar-gets for thepriceofhydrogen fuelwere“equal toorless thanthe fuelcostofgasolineenginevehicles”by2015and“equaltoor lessthanthefuelcostofhybridvehicles”by2020.Consequently,thepriceofhydrogenfuelhasbeensetatalevelthatrealizedthesegoalsafull5yearsaheadofschedule.
OnDecember10,2014 IwataniCorporationsignedacomprehensiveagreementwithSevenElevenJapanCo.tobuildhydrogenstationsandconveniencestoresinthesamefacilities.ItwasannouncedthatthefirsttwosuchfacilitiesarescheduledtoopeninTokyoandAichiPre-fecture in2015 (31). It is thoughtthatasingle locationwhereconsumerscanshopfordailynecessitiesandalsorefuelFCVswillmakeamajorcontributiontoimprovingtheconvenienceandpopularityofFCVs.
JXNipponOil andEnergyCorporation announcedonNovember12,2014that itwouldbeopeningitsfirstcommercialhydrogenrefuelingstation inDecemberofthesameyearandatotalof11suchstationsbytheendof the2014fiscalyear (32). Thefirststation is theDr.DriveEbinaChuoStore thatopenedonDecember25,2014 inEbinaCity,KanagawaPrefecture (33). Therearealsoplanstoopentwoadditionalhydrogenrefuelingstations in thesameprefecture in theIzumiWardandAsahiWardofYokohamaCity. Inaddition, therearealsoplanstoopenonestationinChibaPrefecture,threestations inSaitamaPrefecture, twostations inTokyo,andtwostationsinAichiPrefecture.
charginginfrastructurecontinuestospreadandbecomemorewidelyavailable.ThissectionintroducesthemaintrendsinelectricmotorsandEVcharginginfrastructurein2014.4. 2. Electric motorsTable7showsthemainelectricmotorsusedtopro-
videdrivepower inpassengervehicles sold in Japan.Almostallof thesemotors, regardlessof installation inanHVorEV,areACsynchronousmotorsusingperma-nentmagnets. Theoutputof thesemotorsvaries fromabout2kWforthemotorsused inmildhybridEVstoabout10to40kWinthemotorsforparallelhybridEVs,inwhichthesemotorsmainlyprovidedriveassist.Themotoroutputrises to20 to150kW inhybridsystemsthatenable fullyelectricdriving. Asaresult, there isagreatrangeinmotoroutputdependingonthesizeofthevehicleandthedrivingperformance.Inthecaseofmotorsused inEVs, themotoroutput isusuallyabout30to125kWand,sincethemotoristhemainsourceofpower, thisoutput is largelydependentonthevehicleweight. Thespeedof thesemotorsduringmaximumoutputvaries fromroughlyequivalent to thespeedofagasolineenginetomotorswithhighspeedsof10,000min–1orhigher.Inmostcases,thehighertheoutputofthemotor, thegreaterthechancethat it isalsoahighspeedmotor.
One recent trend influencing the research andde-velopmentofnewelectricmotors is theaimtogreatlyreduceoreliminate theuseof rareearthelementsbyactively seekingmore efficient arrangements for themagnetsandevenadoptingswitchedreluctance(SR)mo-tors,whichusenorareearthelementsatall.Othernewtechnologicaldevelopments, suchasadoptingdifferentwindingwires,arealsobeingpursuedtohelp increaserotationspeedandtoreducesizeandweight.4. 3. Charging infrastructureTheJapanesegovernmentandautomobile industry
groupsare implementingvariouspolicies tohelppro-mote the spread andpopularization of the charginginfrastructure forEVsandPHVs. The followingpara-graphsbrieflydescribethepoliciesbeingimplementedtopromotethespreadandpopularizationof thischarginginfrastructureandtherecenttrendsinbatterychargingtechnologies.4. 3. 1. Policies to promote popularization4. 3. 1. 1. Next-generation vehicle battery charging
In the2012 fiscalyearsupplementarybudget, subsi-diesof100.5billionyenwereenacted for theestablish-mentofacharginginfrastructureandanother30billionyenwasenactedaspartof the2014fiscalyearsupple-mentarybudget. The lattersubsidieswereenacted inanefforttohelpenhancethecontent,suchasbyadding
the establishment ofbillingdevices to the applicabletargetsforthesubsidies,inordertomaketheapplicabletargetseveneasiertouse.4. 3. 1. 2. Establishment of Nippon Charge Service,
Japanese automobilemanufacturers (Toyota,Nissan,Honda, andMitsubishi) topromote the installation ofelectricvehiclechargingdevicesandtobuildupacharg-ing infrastructurenetworkwithahigh levelofconve-nience(45).NCSisaimingtobuildanationwidenetworkof rapidchargers (in thisarticle thismeansachargerwithanoutputof10kWormore)thatareconnectedtoeachotherand thatalluse thesamecommoncard togainaccess. This isbeingcarriedout toeliminate theinconvenienceofneedingaseparatespecificcardtouseeachoftheoldchargingnetworks.AccordingtoapressreleaseonMarch19,2015,NCSisaimingtohavearound11,000chargers in itscharging infrastructurenetworkoperationalbytheendof2015(46).4. 3. 2. State of progressFigure7showsthecumulativenumberofrapidand
normalchargers(inthisarticle,achargerwithanoutputof less than10kW) thathavebeen installed inJapan.However,therapidchargersshowninthefigurearelim-itedtoonlythosethatreceivedCHAdeMOcertification(47).Thefollowingsectionsprovideexamplesanddetailsabout thestateofprogress in installingbothkindsofchargers.4. 3. 2. 1. Rapid chargersThenumber of these chargers thatwere installed
increasedsignificantlystartingat theendof2014dueto the subsidies thatwere enacted. Thedata isnotshown in thegraph inFig. 7,but thenumberof fastchargerswith theCHAdeMOcharging standard thatwere installedoutsideJapanalso increasedsignificantlystartingin2013andthecumulativenumberofoverseas
TheFamilyMartchainofconveniencestores inJa-panannounced inApril2014that itwould installrapidchargersat500ofitsstorelocationsstartinginthesum-merof2014.Accordingtoawebsitethatallowsyoutosearch forFamilyMartstore locations,680storeshaverapidchargersavailableasofApril 17, 2015. This isoneexample ofhow the subsidies from the Japanesegovernmentandtheeffortsofthefourmajorautomobilemanufacturers (Toyota,Nissan,Honda,andMitsubishi)throughthePHV,PHEV,andEVChargingInfrastruc-turePromotionProjecthavebeenutilizedtomaximumeffect.Bysomecalculations,thenumberoffastchargersin Japan increasedbyapproximately 30%within oneyear.
One type of rapid charger that does not use theCHAdeMOstandard is theSupercharger fromTeslaMotors,Inc.(Fig.8)andittoohasbegunmakinginroadsintoJapan.ThischargerisdifferentfromCHAdeMOinthatitcancurrentlyonlybeusedtochargetheModelSluxurysedanEVfromTeslaMotors.AmajorfeatureoftheTeslaSupercharger is that itcanprovideachargeatamaximumof120kW,whichismorethantwotimesgreaterthantheCHAdeMOstandard(max.50kW).AsofApril15,2015, therewere6 locations inJapanwithTeslaSuperchargersandworldwideitisavailablein419locations(2,305chargers)(52).PlanstosetupadditionalSupercharger stations around theworld through theyear2016werereleasedvia theTeslaMotorswebsite.TheModel S is equippedwith aCHAdeMOadaptersothat itcanbechargedusingafastchargerwiththeCHAdeMOstandard,butcurrently there isnoadapterthatallowsEVsdesignedfortheCHAdeMOstandardtomakeuseoftheTeslaSupercharger.4. 3. 2. 2. Normal chargersFigure7showsthat thenumberofnormalchargers
hasbeenincreasingsteadily.Inrecentyearsitismore
Fig. 7 Cumulative number of chargers for EVs in Japan(48)(49)
Number of normal chargers (stand-type) in JapanNumber of rapid charger locations (CHAdeMO standard) in JapanNumber of rapid chargers (CHAdeMO standard) in Japan
10 000
8 000
6 000
4 000
2 000
0
Cumulative number of chargers installed & sold
Jan. 2008
Jan. 2009
Jan. 2010
Jan. 2011
Jan. 2012
Jan. 2013
Jan. 2014
Jan. 2015
Jan. 2016
Fig. 8 Tesla Motors, Inc. Supercharger (Port Island Golf Club in Kobe City, Hyogo Prefecture).
commontohearofsingle locationsequippedwithmul-tiplenormalchargers. In theTokyoMidtownparkingarea,125normalchargerswere installed inDecember2014(54).OnFebruary27,2015,MitsubishiMotorsCo.,Ltd.announcedtheinstallationofatotalof1,154normalchargers in its employeeparking lots to enhance theconvenienceofworkerswhocommute toworkusingEVs(Fig.9).AutobacsSevenCo.,Ltd.announcedinitsCSRandGovernanceReporttheinstallationofchargingstandsat102storesbytheendonMarch2015 (normalchargerswillbeinstalledat98ofthosestores)(55).Inalloftheseinstances,thenormalchargersareprovidedforusersleavingavehicleparkedforanextendedperiodoftime,suchaswhileshoppingorworking.4. 3. 3. Technological trends4. 3. 3. 1. Rapid chargersThe line-upofrapidchargermodelscontinues to in-
creasetomeetthevariousneedsofthe installers. Thenumberofdifferentmodelsthatcanbechosen,startingwith10kWmodels, is increasingtoreducetheburdenoftheelectricpowercontractsontheinstallers.Hybridmodel fast chargerswithan internalbatteryarenowalsoavailable for thissamepurpose. Somemodelsarealsoequippedwith twoconnectors tohelprelieve thestressofEVuserswhomustwaitforotherstofinishbe-forecharging.4. 3. 3. 2. Normal chargersTheestablishmentofbillingfunctionsonnormalchar-