高容量锂离子电池电极材料研究的新进展.ppt

ExplorationresearchofnewcathodematerialswithhighcapacityforLi-ionbatteryYongYangStateKeyLabofPhysicalChemistryofSolidSurface,XiamenUniversityChina

What’arethemajorplayersofthecathodematerialsElectrodematerialsHighenergydensityHighpowerdensityLayeredoxidecathodematerialsPolyanion:LFePO4,Spinel,LiMn2O4﹛HighenergydensityLi2FeMnSiO4;Organic-typeFluorides…

Furtherimprovementoflayeredoxide-basedcathodematerials1)Nickel-basedlayeredcathodematerials:Lattice-dopingSurfacecoating1)H.S.Liu,etal;ElectrochimicaActa,2004,49:1151-1159;SolidStateIonics,2004,166:317-3252),etal;JPowerSources,2004,129(1):101-106;J.Phys.Chem.B;2004,108,17546-175522)Li-richLi-Ni-Co-Mn-Osystem;Verypromisingsystem,stillmorestudyareneeded.E.g.firstcycleefficiency,ratecapability,safetyissues,howchoosesuitableanodesystems….

High-CapacityLi[Li(1-x)/3Mn(2-x)/3Nix/3Co3/x]O2CathodeCharge/dischargeat18mA/g,2.0~4.8VTheinitialdischargecapacityis249mAh/g,about100mAh/ghigherthanthatofLiCoO2.0.1CBareAlF3-coatedCharge(mAh/g)324.5314.0Discharge(mAh/g)249263.1ICL(mAh/g)75.550.9

LayeredOxide-typeCathodeMaterialsHighenergydensitybatteriesLayeredoxidecathodematerialsLi2MnO3.LiNixCoyMn1-x-yO2:~270mAh/gorevenhigher,Gasevolution,e.g.O2,CO2HighcapacitycathodematerialsChargingtohighvoltage

In-situElectrochemicalMassspectroscopictechniquesandItsuseinLi-ionbatteries1AlF3coatinglayerprovidesabufferlayertomakeoxygenatomswithhighactivitycombinetogethertoformO2moleculeswithlowoxidationcapabilitytoelectrolytes.21/43times4

Advantages:LowcostexcellentthermalstabilitynooxygenevolvedatlowamountLi+intercalatedDisadvantages:LowercapacityandlowelectronicconductivityPhosphateshouldbedevelopedasHighPowerDensityandSafeCathodeMaterialsPolyanioncompounds(i.e.LiFePO4)withstableframeworkison