鋰離子電解液的介紹英文PPT

Tip

OfThe

IcebergforElectrolytes

CATALOGUE1.OrganicSolvent2.ElectrolyteSalts3.ElectrolyteAdditives4.Currentdevelopmentsituation

Electrolytesareoneoffourkeymaterial（cathode,anode,electrolytematerialandseparator）andcalledasbloodofLi-ionbatteries.theyareinproportionofpreparationofhighconcentrationorganicsolvent,electrolytesaltandotherrawmaterials.ingivenconditions.1.OrganicSolvent2.ElectrolyteSalt3.ElectrolyteAdditives4.CurrentdevelopmentsituationsolventDECDMCfattypePCECchain:THFDOLorganicsolventethericcycle:DMFDEEsufone:DMSOSL

solventPC(PropyleneCarbonate)C4H6O3EC(EthyleneCarbonate)C3H4O3DEC(DimethylCarbonate)(keytoSEI)DMC(Dimethylcyclosiloxane)

DMCtoday'ssyntheticorganic"newfoundation".DMCIthascompletedtheinsulatingorresistanttohightemperatures,highflashpoint,lowfreezingpoint.Itcanworksbetweenlong-term5℃~80℃,excellentwaterresistence.Non-toxic,insipidity.

DMCtoday'ssyntheticorganic"newfoundation".1Insteadofphosgenebehydroformylationagent.2Insteadofsulfuricacid(DMS)dimethylmethylationagent3

Non(Low)-toxicsolvent.TheinfluenceofsolventcompositionofthecapacityholdingrateandcyclecharacteristicsofLi-ionbatteryNOCompositionofsolvent(V/V)Capacityholdingrate(%)0.2CCapacity/mAh0.5CCapacityratio/%1CCapacityratio/%2CCapacityratio/%Cyclelife1EC+DEC+DMC(3.5:2.5:2.5)92.9263298.696.385.13442EC+DMC+EMC+DEC(4:2:3:1)93.16639`98.594.578.73553EC+DEC+DMC(1:1:0.8)93.6462398.494.479.33974EC+EMC+DMC(1.1:0.9:2.1)91.9362299.096.793.13525EC+DMC(1:1.5)90.3761998.896.393.52451CDischargecurvesofLi-ionbatterycontainngdifferentorganicsolvent1.OrganicSolvent2.ElectrolyteSalt3.ElectrolyteAdditives4.CurrentdevelopmentsituationSoluteLiPF6,LiBF4,LiClO4,LiAsF6,LiCF3SO.Conductivity:LiAsF6>LiPF6>LiClO4>LiBF4Thermalstability:LiAsF6>LiBF4>LiPF6Resistncetooxidation:LiAsF6>LiPF6>LiBF4>LiClO4CharacteristicsofsaltElectrolytesaltadvantagesdisadvantagesLiClO4HighconductivityStrongoxidantBadhightemperaturePerformanceandunsafeLiAsF6HighconductivityGoodthermalstabilityToxic,highcostLiPF6HighconductivityBadthermalstabilitySensitivetowaterLiBF4HighconductivityBadthermalstabilityAtpresentLiPF6isthecommonlithiumsaltwhichusesincommoditylithium-ionbatteries.LiPF6haspoorhydrolysisstabilityandthermalstabilityandthehydrolysisproductHFwouldadverselyaffectedtheperformanceofbattery.TheeffectiveSEIfilmformedinthesurfaceofthenegativeelectrodeonlywhenLiPF6andethylenecarbonate(EC)combiningused.Buthighmeltpoint(37℃)ofECbecomethelimitationoftheusingofbatteriesatlowertemperature.Facethesechallenges,whatwecando?LiBOBorLiPF6,

whichissuitable?Sinceanewlithiumsalt-lithiumbis(oxalate)boratewasdisclosedbyLischka1999firstly,anditwassuccessfullysyntheticedbytheunitedstatesairforcelaboratoryin2000.Anovellithiumsalt,(LiBOB),whichpossessesgoodfilm-formingpropertyandhighthermalstability,isbecomingthemostpotentialsalttoreplacecommercialLiPF6forlithium-ionbatteryelectrolytesinrecentyears.LiBOBScience(2006256~257)

Duringallreactionandpurifyingprocedureamongelectrolytesolution,LiBOBhasgoodcrystalline,everyneedle-shapeparticleisabout10umlongand2umwidemagazines

Twosalts,haveeachtheirpreponderance

Twosalts,haveeachtheirpreponderanceRoomtemperature

65℃

LiBOBLiBOBformedagoodcrystallinephaseandasshowinXRDpatterns,theimpurityreduced.TheconductivityofLiBOBbasedelectrolyteisthehalfofthatofLiPF6counterpartfrom0℃to80℃.Inhalfcell,LiBOBhasasuperiorcharge-dischargecapacityatelevatedtemperaturethanthatofLiPF6Facethesechallengeswhatwecando?Electrolyteadditivesareoneofsignificantmeasurementsforsafetycurrentlyrecognizedoflithiumbatteries.Youcanimprovetheallkindsofperformancebyaddingdifferentadditives.

1.OrganicSolvent2.ElectrolyteSalt3.ElectrolyteAdditives4.CurrentdevelopmentsituationElectrolyteadditives–threeprimaryfunctions1、ontheconductivityFreezingpoint,viscosity,dielectricconstantanddonatingnumberofsolvent.Eg:LiPF6,LiBF4,LiClO4,LiAsF6,LiCF3SO.DMC,DEC,EMC`````1.ontheconductivitySalt(1mol/L)Co-soventSpecificconductivity(ms/cm)Li(CF3SO2)2NDMC9.2DEC6.5MP8.8LiPF6DMC11.2DEC7.8MP10.3Electrolyteadditives–threeprimaryfunctions2、OnthesolidelectrolyteinterfaceItispossibletomodifytheanodesurfacechemistrybyusingactiveadditivesinsolutions,whosereductionmayformhiglycompactinsolublefilms.Eg:PC-basedelectrolyte

VinyleneCarbonatetoformastableSEIlayer.VinyleneCarbonatetoformastableSEIlayer.Q↑C↑ξ↑AddVCquantityandcirculationperformancerelationship0.3C1CAddVCadditivesanddifferenttemperaturedischargeproperties50℃-20℃Electrolyteadditives–threeprimaryfunctions3、OnotherprotectionfunctionsProtectthepositiveactivesubstances,stableLiPF6,improveoverchargesafetyandflameretardantfunctionsEg:(1.)3-Chloroanisole,blockingvoltageincreasesabove5.3V.(2.)Adddiethylphosphonate(DECP),ammoniumperfluorocaprylate(APC)

couldimprovetheflameretardedperformanceofelectrolyte

APC-flameretardedperformanceFlamepropagationrateof1mol/LLiPF6/EC,DMCelctrolytecontaining(a)0.0and(b)0.70wt%APCinUL94flammabilitytest

DSCcurvesoffullylithiatedMCMBelectrolytescontaining(a)0.0and(b)0.10wt%APCto0.01VconclutionTheelectrolyteplaysanimportantroleonthebatteryperformance.Theconductivityoftheelectrolyte,thecyclelifeand

SEIstabilityofthebatteryarecloselyrelatedtothesolvent,additiveandthepurityoftheelectrolyte.1.OrganicSolvent2.ElectrolyteSalt3.ElectrolyteAdditives4.CurrentdevelopmentsituationCurrentdevelopmentsituationofGloballithiumbatteries

AnalysisaboutLiPF6ofglobalproductionforecast