白皮书 2030 年电池创新路线图part2

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TECHNICALANNEX

PbLiNiNa

Contents

SCOPEANDPURPOSEOFTHETECHNICALANNEX

4

PARTI:IDENTIFIEDBATTERYTECHNOLOGIESANDTHEIRPOTENTIAL

5

A.MAINSTREAMBATTERYTECHNOLOGIESANDTHEIRINNOVATIONPOTENTIAL

5

A.1.Lead-basedbatteries

6

A.2.Lithium-basedbatteries

7

A.3.Nickel-basedbatteries

9

A.4.Sodium-basedbatteries

10

B.FUTUREBATTERYTECHNOLOGIESANDTHEIRPOTENTIAL

11

PARTII:BATTERYEND-USERAPPLICATIONR&DFOCUSAREA

16

A.R&DAREA-AUTOMOTIVEMOBILITY

16

A.1.Automotive12Vauxiliarybatteries

17

A.2.Automotive12VStart-Lighting-Ignitionbatteries(SLIbatteries)

19

A.3.Heavycommercialvehiclestand-bybatteries

20

A.4.AutomotiveHybridElectricVehiclepropulsionbatteries(HEVs)

21

A.5.AutomotiveBatteryElectricVehicles(BEVs)

22

B.R&DAREA-MOTIVEPOWERMATERIALHANDLINGANDLOGISTICSAPPLICATIONS

24

C.R&DAREA-MOTIVEPOWEROFF-ROADTRANSPORTATION

25

C.1.Batteriesinoff-roadindustrialvehicles

25

C.2.Batteriesinrailwayapplications

26

C.3.BatteriesinMarineapplications

27

C.4.BatteriesinAviationapplications

30

D.R&DAREA:BATTERIESFORSTATIONARYENERGYSTORAGE

32

D.1.Batteriesforuninterruptedpowersupply(UPS)

32

D.2.BatteriesforTelecom(TLC)

34

D.3.Batteriesforresidentialandcommercialenergystoragebehindthemeter

36

D.4.Batteriesforutilitygrid-scalestorage(large-scaleESS–infrontofthemeter)

38

D.5.Batteriesinoff-gridapplications

40

BATTERYINNOVATIONROADMAP2030

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ScopeAndPurposeOfTheTechnicalAnnex

ThisTechnicalAnnextotheEUROBATWhitePaper‘BatteryInnovationRoadmap2.0’providesthereaderwithmorein-depthtechnicalbackgroundonthestate-of-playandinnovationpotentialofthemainstreamlead-,lithium-,nickel-andsodium-basedbatteries,aswellasonpromisingfuturebatterytechnologieswithahorizonupto2030.TheAnnexconsistsoftwomainparts.

Thefirstpartanalysesthestate-of-the-artandpotentialforimprovementofeachidentifiedbatterytechnologyinrelationtotheirintrinsicperformance,safetyandenvironmentalaspects.

Asbatteriesaredesignedtobeusedinparticularapplications,thesecondpartoftheAnnexisevenmoreimportantandanalysesthemainstreambatterytechnologiesusedincriticalapplicationsinsupportoftheobjectivesoftheGreenDeal.InthispartII,thebatteryKPIsareconsideredperapplicationastheinnovationpriorityareasforthedifferentmainstreambatterytechnologiesarestronglylinkedtothis.

BATTERYTECHNOLOGIESANDAPPLICATIONS

PbLiNiNa

LEADBASED

LITHIUMBASED

NICKELBASED

SODIUMBASED

ADVANTAGES

ADVANTAGES

ADVANTAGES

ADVANTAGES

Affordable,provensafe

Highenergydensity,

Longlife,

Relativelyhighenergy

andsustainable

lowweight

reliability

density,lowweight

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BATTERYINNOVATIONROADMAP2030

IdentifiedBattery

Part1

Technologiesand

theirpotential

ThebatterytechnologiesconsideredinthisWhitePaperhavebeenselectedbecauseoftheirpotentialforfurtherimprovementandtheircontributiontomeetingtheobjectivesoftheEuropeanGreenDealandthenewBatteriesRegulationthatisunderdevelopment.

Thefirstchaptercoverstoday’smainstreambatterytechnologies(lead-,lithium-,nickel-andsodium-based),whilstthesecondchaptercoversthemostpromisingupcomingtechnologiesidentifiedtocomplementtheprogressmadeintheexistingtechnologies.

A.

Mainstreambatterytechnologiesandtheirinnovationpotential

Decadesofmarket-drivenR&Dhasresultedinawidevarietyofcommerciallead-,lithium-,nickel-andsodium-basedbatteryproducts.Thislargevarietyofproductsistheresultofincrementalimprovementsintroducedoverdecadestofitthespecificneedsoftheapplicationsandtheirever-increasingdemands.

Today’smainstreamlead-,lithium-,nickel-andsodium-basedbatterytechnologiesstillhaveinnovationpotentialtocontinueservingfurtherevolvingmarkets.Assuch,theyshouldbeconsideredaskeytechnologiestofurtherreduceCO2emissionsandtomakeEuropelessdependentonenergyandrawmaterialimports,alsoby2030.

Thischapterhighlightstheinnovationsofeachofthevariousmainstreamchemistries.However,itshouldbestressedthatcombiningbatterychemistrieswithinthesameapplicationalsoprovidessynergies,suchasindevelopmentsformild-hybridEVsorinBEVs,wheretheHVlithiumpropulsionbatteryissupportedbytheLVadvancedleadbatterytoensurethefunctionalsafety.

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A.1.Leadbasedbatteries

Pb

State-of-the-art

Theleadbatteryhasbeenthepredominantenergystoragedevicefortheindustrialandautomotivemarketsforover100years.Differentdesignsoflead-basedbatteriesareavailable,withanimportantchoicetobemadebetweenfloodedor‘vented’,requiringmaintenance,ormaintenance-freevalve-regulated(VRLA)batteries.TheycanbeconnectedinlargebatteryarrangementswithoutsophisticatedmanagementsystemsandaredifferentiatedfromtheothertechnologiesbyalowcostperkWhinstalledandlowcostperkWhelectricitythroughput.

Itisoftenoverlookedthattheleadbatteryhascontinuouslyinnovatedin

responsetonewrequirementsintermsoffunctionality,durabilityandcost.The

recentmainstreamintroductionsofabsorptiveglass-mat(AGM)batteries,enhancedfloodedbatteries(EFBs),batterymonitoringsensorsandbatterymanagementsystems(BMS)areobviousexamplesofcontinuousimprovement.

Improvementpotential

Tocompetewithupcomingelectrochemicalstoragetechnologies,thereisaneedtoacceleratethepaceofinnovation.Thiscouldbethroughabetterdynamiccharge-acceptanceatuncompromisedhightemperaturedurabilityorbyimprovingtheenergyandpowerdensitieswithimprovedcycle-life.Specificpowercouldbeimprovedbydevelopingnewadvancedadditivestodecreasetheinternalresistance,whilethecyclelifecouldbelengthenedthroughdesignenhancements,suchascorrosion-resistantlead-alloys.Moreintelligentbatteryoperationmodescouldalsobedeveloped.

Apartfromfundamentalresearchtoimprovetheelectrolyte,thematerialsandthecomponentsused,otherimprovementscanstillbemade.Theseincludematerialinnovationsonsyntheticexpanders,nano-basedcarbonmaterials,newalloycompositionsandimprovedThinPlatePureLead(TPPL).Alsobipolarcelldesignwillbekeydevelopmentsforlead-basedtechnologiestofurtheradvanceinviewoffuturerequirementsinamultitudeofapplications.TPPLandCarbonEnhancedarepromisingcandidatesforincreasedservicelife,PSOCoperationandimprovedpowerdensity.

Theoutstandingfeatureinthisprocessisthattheseimprovementshavebeentailoredtotheparticularapplication.

Environmentalaspects

Occupationalexposuretoleadisnowundercontrolbecausethebatteryindustryhasproactivelytakenmeasurestolimittheexposureofitsemployeestobloodleadcontaminationduringthemanufacturingprocess.Europeshouldallowthemarkettodrivechangeandrecentprogressonleadbatteryresearchshouldnotbediscounted.Thefurtherdevelopmentofleadbatteriesinavarietyofenhancedtechnologieswillserveapplicationsthatcancontributetotheachievementofthezero-emissionstargetsintheEuropeanGreenDeal.

Lead-basedbatterycirculareconomytargets

Recyclingtargetsforleadbatterieswillbemaintainedataveryhighlevel,withefficiencyover90%andrecyclingofactivematerialsat99%,achievingacirculareconomy,whichwillbenefitthewholebatteryvaluechainandimproveEurope’sindependencyonrawmaterialsimportsneededtobuildthebatteries.

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A.2.Lithium-basedbatteries

State-of-the-art

Li

Lithium-ion(Li-ion)isconsideredtheleadinglithiumtechnologyforautomotiveandindustrialapplicationsandwillremainsoin2030.Lithiumiscurrentlydeployedinmass-producedstandardcelltypesindifferentapplications–astrategydrivenbycostandsafetyreasons.Themajorrequirementforhigherenergydensitiestoachieveincreaseddrivingrangeisdirectlylinkedtoe-mobility.Thisresultsinadevelopmentroadmapfor2030thatmainlyconsidersthelithium-basedtechnologiesbasedonmodifiednickelcobaltmanganeseoxide(NMC)materials,fromNMC111toNMC811,withincreasednickelandreducedcobaltcontentincombinationwithhighcapacitiveanode

materialswithcarbon/siliconcomposites.Solidstatetechnologyshouldalsobetargetedtoincreasetheenergydensityandimprovethesafetyaspect.TheLi-iontechnologiesconsideredinthisRoadmapconsistofacombinationofthefollowingavailableanodeandcathodematerials:

Tabulation:SpecificcapacitiesofanodeandcathodematerialsofLi-ionbatteriescoveredinthisRoadmap

Improvementpotential

ThedevelopmentroadmapforLi-ion,Ni-richNMCpositiveelectrodematerialsandnewmaterialsforthenegativeelectrode(e.g.Si/Ccomposite)consideredforfuturedevelopmentare:

•Generation2a:NMC111/100%C

•Generation2b:NMC523-622/100%C

•Generation3a:NMC622/C+Si(5-10%)

•Generation3b:NMC811/Si/Ccomposite

Chart:Generationoflithiummaterialsconsideredforfurtherdevelopmentby2030

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Duetothevarietyofpossiblecombinationsofcathodeandanodematerials,theresultingLi-ionbatteriesshowspecificandindividualperformancecharacteristicssuitablefordifferentkindsofapplications.ThedevelopmentofLi-iontechnologiessuitableforindustrialandautomotiveapplicationsisstillachallengeintermsofmaterialresearchprocess,production,development,recycling,safetyandtransportation.

Requirementsforcathodematerials

•Highspecificenergy(mAh/g)

•Safety

•Stability(cycleandcalendric)

•Highvoltage

•Lowpolarisation

•Lowprice

•Lowcontentofrarematerials(e.g.cobalt)

•LowCO2footprintatproduction

•Environmentallyandethicallyharmless

•Easyprocessing

•Availability

•Highpowercapability

Economicandsafetyrequirements

•Lowprice

•Easyprocessing

•Environmentallysafeandethical

•Operationallysafe

Challengesidentified

•Productionprocesses

•Recyclingprocesses

•Transportation

Environmentalaspects

Inordertoreducetheenvironmentalimpactandimprovingtheavailabilityoflithiumbatterycomponents,astrongpushisexpectedinresearchaimedatreducingthecontentofrarematerials(Cobalt),atresearchingalternativematerials,activatingextractionprocessesenvironmentallysafeandethicallysoundminingandmanufacturing,andalsoadevelopmentoflow-carbonmanufacturingprocesses.

Lithiumbasedbatterycirculareconomytargets

Recyclingtargetsforleadbatterieswillbemaintainedataveryhighlevel,withefficiencyover90%andrecyclingofRecyclingtargetsforlithiumbatterieswillbemaintainedatthecurrentlevelof50%,butactivematerialrecyclingisexpectedtoincreasefrom65%toreach85%by2030.Therecoveryofnickel,cobaltandlithiumwillalsobefullycommerciallyviableinfuture.

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A.3.Nickel-basedbatteries

Ni

State-of-the-art

Nickel-basedbatteriesarethetechnologyofchoiceforapplicationsusedinextremeclimate,cyclingorfastchargingconditions.Differentdesignsareavailable:pocket,sintered,plastic-bonded,nickelfoamandfibreelectrodes.Cellsareprismaticorspiralwound,flooded(or‘vented’)orvalveregulated,thelatteralsobeingmaintenancefree.Thankstodecadesofsafeuseunderthemostextremeoperatingconditionsandcontinuousdevelopment,nickel-cadmiumismostlyusedinspecialandnicheapplications.

Improvementpotential

Usinginnovativematerials,thistechnologycanbefurtherdevelopedforexistingapplicationsandasareplacementsolutionwithitskeyperformancepropertiesinextremeconditionshavingthepotentialforfurtherimprovement.Nickel-basedbatteriesareamongtheelectrochemicalstoragesystemsthatshouldbeconsideredforindustrialapplicationsoverthenextdecade.

Environmentalaspectsandcirculareconomytargets

Recyclingefficiencyshouldincreasefromthecurrent79%(activematerialsat50%)to80-85%(activematerialsat55-60%)by2030toreachabreak-evenbusinessmodel

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A.3.Sodium-basedbatteries

Na

State-of-the-art

Incontrasttootherbatterytypes,high-temperaturebatteriesconsistofliquid-electrodesandasolidelectrolyte,usuallyanion-conducting(e.g.Na+)ceramic.Thesebatteriesrequirerelativelyhighoperatingtemperaturesof>300°Ctokeepthesodium-basedelectrodeintheliquidstateandtoincreasetheconductivityofthesolidelectrolyte.

Commerciallyavailablerepresentativesaresodiumnickelchloride(NaNiCl),alsoknownasthe‘Zebra’battery(ZeroEmissionBatteryResearchActivities),andthesodium-sulfurbattery(NaS).

Sodiumnickelchloridebatteries:Thecathodemainlyconsistsofaporousnickelmatrixasacurrentconductorwithnickelchloride(NiCl2),whichisimpregnatedwithsodiumaluminumchloride(NaAlCl4).Theanodeismadeofsodium.Ceramicβ-aluminumoxideisusedastheseparatorandelectrolyte,butthesodiumionsdonotallowelectronstopassbetweentheanodeandcathode.Theoperatingtemperatureofthistypeofbatteryisbetween270°Cand350°Csothattheelectrodes(activematerial)areintheliquidstate(melted)andtheceramicseparatorachieveshighconductivityforsodiumions.Thespecificenergyofthecellsisapproximately120Wh/kgatanominalvoltageof2.3Vto2.6V.Advantagesoverthesodium-sulfurbatteryaretheinversestructurewithliquidsodiumontheoutside,whichallowstheuseofinexpensiverectangularsteelhousingsinsteadofcylindricalnickelcontainers.Theassemblyissimplifiedinthatthebatterymaterialscanbeusedintheunchargedstateassodiumchlorideandnickel,andthechargedactivematerialsareonlygeneratedinthefirstchargingcycle.Sodiumnickelchloridebatteriesareusedinsmallseriesofelectricvehiclesinfleetsandforstationarystorageapplications.

Sodium-sulfur(NaS)batteries:Thecellsconsistofananodemadeofmoltensodiumandacathodemadeofgraphitefabricsoakedwithliquidsulfurinordertoachieveelectricalconductivity,assulfurisaninsulator.AsinthecaseoftheNaNiClbattery,thesolidelectrolyteβ-aluminumoxideisusedastheelectrolyte,whichbecomesconductiveforNa+ionsaboveatemperatureofapprox.300°C.Theoptimumtemperaturerangeisbetween300°Cand340°C.Duringthedischargeprocess,positivelychargedsodiumionsenterthesolidelectrolytefromtheliquidsodium,releasingelectrons.Thesodiumionsmigratethroughtheelectrolytetothepositiveelectrode,wheretheyformsodiumpolysulphides.Thecellvoltageis2V.Thisprocessisreversedduringcharging.Amajoradvantageofthesodium-sulfurbatteryisthattheinternalresistanceofthecellisalmostindependentofthestateofcharge.Itonlyrisessharplytowardstheendofthechargebecausethereisadecreaseinsodiumionsintheelectrolyte.

Therequiredoperatingtemperatureismaintainedinnormaloperationbythepowerdissipationofthecellsthemselves;instand-byoperationitisachievedbyanadditionalelectricheater,whichincreasesthebattery’sownconsumption.

TheNaSbatteryhasavolumetricenergydensityofabout367Wh/landgravimetricenergydensityof222Wh/kg.Oneadvantageofthisbatteryisthehighcyclestabilityofover4,500cyclesandalongcalendarlifeofover15years.Thetechnologyhasbeencommercialisingsince2002,mainlyforlargescalestoragewithmorethan1MWhofenergy.

NaNiClandNaSbatterieshaveaservicelifeofaround4,500cyclesandanefficiencyof75%to86%.Ifnecessary,thermallossesduetoheatingnecessarytomaintainthecelltemperaturemustbetakenintoaccount,iftherearelongerperiodsoftimebetweencharginganddischarging.Thiscanbeinfluencedwithincertainlimitsthroughacorrespondingeffortinthermalinsulation.

Environmentalandcirculareconomytargets

NaNiClbatteryproductionisrelativelyenergy-intensiveandthereforehasthehighestshareofenvironmentalimpact(dependingontheheatsupplysource).Otherfactorsarethehighdemandfornickelandthecomplexmodularconstruction(insulation).Thenickelcontentinthebatterycanberecovered,whichcanbeusedinthesteelindustry.Theceramiccontentinthecells,aswellasthesaltcollectedintheresultingslag,canbeusedinroadconstruction.Regardingthemanufacturingprocess,theproductionoftheβ-aluminumoxidesolidelectrolyteisconsideredtobeenergy-intensive.NaSbatteriesalsocontainlargeproportionsofsteelandaluminum,whichcanberecycledaccordingly,leadingtoareductioninthepossibleenvironmentalimpact.

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B.

Futurebatterytechnologiesandtheirpotential

Intheframeoffurtherimprovementsinperformancerequirementsofbatteriesinreallifeapplicationsanddrivenbydurability,safety,sustainabilityandaffordability,industryexpertshavereachedconsensusonwhichpromisingfuturetechnologiestoconsiderinthecurrentroadmap.Withsustainabilityasakeydriverwiththepurposeofproducingbatteriesatthelowestpossibleenvironmentalimpact,materialsthathavebeenobtainedinfullrespectofsocialandecologicalstandards,arelonglastingandsafe,andthatcanberepaired,reusedorpotentiallyrepurposedshouldbeused.Inthissensetheessentialelectrochemicalstoragesystemsidentifiedarelistedhereunder.

B.1.Leadbipolarbatterytechnology

Whilebipolarandmonopolardesignssharethesamelead-basedchemistry,theydifferinthatinbipolarbatteries,thecellsarestackedinasandwichconstructionsothatthenegativeplateofonecellbecomesthepositiveplateofthenextcell.Thecellsareseparatedfromeachotherbythebipolarplate,whichallowseachcelltooperateinisolationfromitsneighbour.Stackingthesecellsnexttooneanother(figurehereunder)allowsthepotentialofthebatterytobebuiltupin2Vincrements.Sincethecellwallbecomestheconnectionelementbetweencells,bipolarplateshaveashortercurrentpathandalargersurfaceareacomparedtoconnectionsinconventionalcells.Thisconstructionreducesthepowerlossthatisnormallycausedbytheinternalresistanceofthecells.Ateachendofthestack,singleplatesactasthefinalanodeandcathode.Thissimplerconstructionleadstoreducedweightsincetherearefewerplatesandbusbarsarenotneededtojoincellstogether.Thenetresultisabatterydesignwithhigherpowerthanconventionalmonopolarlead-basedbatteries.

Figure:Bipolardesign-thecellsarestackedinasandwichconstruction

Untilrecently,themainproblemlimitingthecommercialisationofbipolarlead-acidbatterieswastheavailabilityofalightweight,inexpensiveandcorrosionresistantmaterialforthebipolarplate,andthetechnologytoproperlysealeachcellagainstelectrolyteleakage.

Architecturaladvantagesare:

•Directcurrentpath=lowimpedance

•Uniformcurrentdensity=highmaterialutilisation

•Thinactivematerialandseparator=highpower

•Pb-Bipolartechnology=increasedenergydensity:50–63Wh/kg

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B.2.Sodium-ionroomtemperaturebatteries

Incomparisontothestate-of-the-arthightemperaturesodiumbatteries,theupcomingnewsodium-ionbatterytechnologyisoperatingatroomtemperature.Thesodium-ionbatteryhasasimilarworkingprincipletotheLi-ionbattery.Sodiumionsalsoshuttlebetweenthecathodeandtheanodetostoreandreleaseenergy.AssodiumresourcesarecheapandwidelydistributedandconsideringthetechnologicalsimilaritieswithexistingLi-ionbatteries,theindustrialisationprocessofsodium-ionbatterieswillbeaccelerated.

Forcathodematerials,themostimportantpartofsodium-ionbatteries,Prussianblueanalogue,layeredmetaloxides,andNASICON(sodium(Na)SuperIonicConductor),eachhasitsownadvantagesindifferentaspects.

Basedonpotentialapplicationscenarios,higherenergydensity,longercyclelifeandbetterlowtemperatureperformancearethemostcriticalindicators.Intotal,thecostandsafetyadvantagesofsodiumbatterieswillgraduallygaininprominence.Therefore,itislikelythatsodium-ionbatterieswillbeusedastractionbatteriesintwo-wheeledvehicles,suchase-scooters,12Vstarterapplications,A0andA00passengervehiclesforA-levelEVcharging,andelectricalenergystorage(EES),asaneffectivesupplementtoLi-ionbatteries.

Thespecificcapacitiesofanodeandcathodematerialsare:

Anode:

•C:300-500mAh/g

•Sn:500-1,000mAh/g

Cathode:

•PrussianBlueAnalogue:120-160mAh/g

•LayeredMetalOxide:100-180mAh/g

•NASICON:100-140mAh/g

Sodium-basedbatterycirculareconomytargets

Recyclingtargetsforsodium-ionbatterieswillbemaintainedatthecurrentlevelof50%,butactivematerialrecyclingisexpectedtoincreasefrom50%to90%by2030.

Generationsofsodiummaterialsconsideredforfurtherdevelopmentby2030are:

State-of-the-art

NaS,NaNiCl

>2023

Na-ion(RT)

>2025

HighEnergyDensityNa-ion(RT)

>2030

AllSolidState

Sodiumbasedtechnologies-keyperformanceparametersforstate-of-the-artin2023andtargetsfor2030:

Sodium-ion2023

Sodium-ion2030

RecyclingRate(%)

50

90

CalendricLife(years)

15

30

EnergyThroughput(FCE)

4000

6,000-12,000

FastRechargeTime(min)

30

5

VolumetricPowerDensity(W/l)

500

600-850

GravimetricPowerDensity(W/kg)

300

380-700

VolumetricEnergyDensity(Wh/l)

310

350-700

GravimetricEnergyDensity(Wh/kg)

160

200-450

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B.3.PostLi-ionbatterytechnologies

Inexpensiveandenvironmentallyfriendlymetalssuchassodiumandpolyvalentlightmetalsshouldonedayreplacelithiumbatterytechnologies.Amajorchallenge,however,isthedevelopmentofdurableandstableelectrodeswithhighenergydensityand,atthesametime,fastcharginganddischargingrates.

LithiumTechnologyRoadmap

Figures:LithiumtechnologyRoadmap(>2025):Gen.3.advancedLi-Ion;Gen.4.Solid-state;Gen.5post-Li-ion

Lithiumall-solid-state(Gen.4)

Solidstatebatteriesuseanelectrolytemadeofsolidmaterialinsteadoftheusualliquidelectrolyte.Theelectrodesarealsomadeofsolidmaterial.Withsolidstatebatteries,thereisthepossibilitythatpartofthesolidelectrolytecanbeincorporatedintotheelectrodes.Forexample,lithiummetalanodescanalsobeused,whichfurtherimproveperformance.Themainadvantagesoffuturesolidstatebatteriesarethattheenergydensityofthecellswillincreasesignificantlyinthefutureandtheriskoffirewillalsodecreaseduetothelesspronouncedflammabilityo