阿贡实验室富锂锰高容量正极材料合成工艺和设备

IV.B.3.6CathodeProcessingComparisonStudy(ANL)IliasBelharouakArgonneNationalLaboratory9700SouthCassAvenueArgonne,IL60439-4837Phone:[phone];Fax:[phone]E-mail:[e-mail]:GaryKoenig,DapengWang,HuimingWu,KhalilAmine,GregKrumdick,ArgonneNationalLaboratoryRichAxelbaum,WashingtonUniversityinSaintLouisStartDate:January,2011ProjectedEndDate:September,2014Objectives·TheobjectiveofthisworkistodevelopabettercorrelationbetweentheelectrochemicalpropertiesofahighcapacityNMCmaterialanditsstructural,morphological,andphysicalproperties:·DevelopacomparativestudyattheleveloftheNMCprecursors.·ComparetheelectrochemicalperformanceofNMCtypecathodesmadethroughdifferentsyntheticroutes.·AssistthematerialsscreeningandcellfabricationeffortsthroughthesamplingofNMCcathodes.·Assistthematerialscaleupeffort.TechnicalBarriersTheprimarytechnicalbarrieristhedevelopmentofasafecost-effectivePHEVbatterywitha40mileallelectricrangethatmeetsorexceedsallperformancegoals.·Developcosteffectivesyntheticmethodsforthescaleupoftransitionmetalprecursors.·Synthesizehighcapacitymaterialswithhighpackingdensity,sphericalmorphology,andsuitableporosity.·ComprehendtheinconsistenciesandfluctuationsoftheelectrochemicalresultsinNMCtypecathodes.TechnicalTargets· EstablishacomparativestudyattheNMCprecursorusingthreesyntheticroutes:hydroxide,carbonate,andoxalateprocesses.· EstablishacomparativestudyattheleveloftheNCMmaterialsandlinktheresultstotheprecursorsstudy.Accomplishments·Prepared(NixMnyCO3)(x=0.2,0.25,and0.3;x+y=1)carbonateprecursorusingacontinuousstirredtankreactor(CSTR)atthepilotscalelevel.·InvestigatedthenucleationandgrowthofprecursorparticlesduringtheCSTRprocessbymonitoringparticlesizedistributions,particlemorphologies,chemicalcompositions,andstructureswithtime.·Investigatedtheelectrochemicalperformanceofthefinallithiatedcathodematerials.·Initiatedthehydroxideco-precipitationprocess·Transferredthecarbonateprocesstechnologyforthepurposeofmaterialsscaleup.IntroductionCompositelithium-andmanganese-richLi1+xM1-xO2compounds(M=Mn,Ni,Co)havebecomeattractivecathodematerialsbecauseoftheirhighcapacity(200mAh/g)andenhancedstructuralstability.Theelectrochemicalperformanceofthesematerialsstronglydependsuponthephysicalpropertiesoftheprecursormaterialsthatserveassourcesforlithiation.IncurrentLi­ionbatterymaterials,hydroxideco-precipitationislargelyusedtoproducetransitionmetalhydroxideprecursors.Carbonateco-precipitationhasalsoemergedasanalternativemethodtoproducetransitionmetal(Mn,Ni,Co)precursors.Themainadvantageisthatinthecarbonatematrix,theoxidationstateofthecationsiskeptas2+foralltransitionmetals.Also,theexperimentalconditionsunderwhichcarbonatesareusuallymadearelessharshthanthoseofthehydroxideprocess,namely,thepHvalueisusuallycloseto8.Co-precipitationinthecontinuousstirredtankreactor(CSTR)isusedhereforthesynthesisofsmallquantitiesofcarbonateprecursorsduetoitsadvantagessuchashomogeneouscomposition,narrowparticlesizedistribution,hightapdensity,andfacilescale­uptoafewhundredsofgramscollectedoverashorttime.ThepresentresearchgivesinsightsintothenucleationandgrowthmechanismofcarbonateprecursorspreparedbytheCSTRco-precipitationprocess.OurgoalwastodeterminetheCSTRexperimentalconditionsthatinfluencethechemicalhomogeneity,morphology,andphysicalpropertiesofcarbonateprecursors(and,subsequently,theFY2011AnnualProgressReport349 EnergyStorageR&DIV.B.3.6CathodeProcessingComparisonStudy(ANL)Belharouak–ANLelectrochemicalcharacteristicsofthefinalmaterials)duringproduction.ApproachThreesyntheticroutes,hydroxide,carbonate,andoxalateprocesses,willbedevelopedtopreparetheprecursorsthatwillservetoproducehighcapacitycathodematerialsLi1+t(NixCoyMnz)1-tO2(t0,x+y+z=1).Acomparativestudyusingthethreerouteswillbemadeusingmaterialsmorphology,physicalcharacteristics,andelectrochemicalproperties.Blendingbetweenmaterialsmadethroughthecarbonateorhydroxideprecursorsandthesamecompositionsmadethroughtheoxalatewillbedonetogetthemostuseofthehighpackingdensityforhighenergydensityandhighporosityforhighratecapability.ResultsNickelsulfate,manganesesulfate,sodiumcarbonate,andammoniumhydroxidewereusedasthestartingmaterialstoprepareNi0.3Mn0.7CO3precursor.Aschematicofthewater-jacketedCSTR(4Lcapacityreactor)systemisshowninFigureIV-64.Productoverflowwasperiodicallycollectedduringtheexperiment,andtheparticlesizedistributionwasmeasuredwithaparticlesizeanalyzer.Theprecursormaterial,whichwasusedtopreparethecathodematerials,wascollectedfromhour5tohour8oftheprocess.FigureIV-64:SchematicdrawingofCSTRsystemusedforthisexperimentFigureIV-65showstheparticlesizedistributionofparticlescollectedduringthe8hoursofCSTRco­precipitation.Attheverybeginning,theparticledistributionwasunexpectedlybroad,withparticlesizesrangingfrom1to80μm.Wespeculatedthelargeparticleswereformedbyagglomerationofverysmallseedswhichislikelyduetotheelectrostaticforceorsurfacetensionbetweentheseedparticles.Astimeelapses,theparticlesizedistributionnarrowedslightly,andthedistributionmaximumshiftedtoacenteraround20μm.Inaddition,a