锂离子电池技术的发展方向-英文版

LiFePO4CompositeCathodeswithConductingPolymers4YunhuiHuang(黄云辉),JohnB.Goodenough2009.10.17.E-mail:yhhuang@HuazhongUniversityofScienceandTechnology（华中科技大学）TheUniversityofTexasatAustin（得州大学奥斯汀分校）OutlineIntroduction123OurStrategyResultsandDiscussion4ConclusionsandProspectsOutline1IntroductionDevelopmentofLi-ionBatteriesHigh-PowerLi-ionBatteriesHighSafetyLowCostLongLifeNopollutionCathodeMaterialsMainCathodMaterialsCo-based

LiCoO2Mn-basedLiMn2O4LiNi0.5Mn1.5O4Multi-elementsLiNixCo1-x-yMyO2P-basedLiMPO4

▲

LiFePO4LiNi2/3Mn1/3O2

▲LiFePO4

AsACathodeMaterialJ.GoodenoughandK.Padhi,J.Electrochem.Soc.,1997,144,1188.OlivineStructure(LiFePO4)HeterositeStructure(FePO4)MainProblems:(1)Lowratecapability;(2)Lowtapdensity;(3)Poorlow-temperatureperformance;(4)Patent.Advantages:Competitivetheoreticalcapacity(170mAh/g);Stablevoltage(3.4V);Low-cost;Environmentallybenign;Safety.ModificationTechnologyofLiFePO4RatecapabilityEnhanceelectronicconductivityImproveLi+diffusionchannelsC-coatingM-dopingNano-sizeSolidsolutionMilestonesof

LiFePO4DevelopmentA.Padhi,K.Monjundaswamy,J.B.Goodenough,J.Electrochem.Soc.,1997,144:1188------Firstreport(2002:PhostechLithiumCo.)

N.Ravet,J.B.Goodenough,S.Besner,M.Simoneau,P.Hovington,M.Armand,Paper127,TheElectrochemicalSocietyMeeting,Honolulu,HI,Oct17-22,1999.-------CarboncoatingS.Y.Chung,J.T.Bloking,Y.M.Chiang,Nat.Mater.,2002,2:123-128------DopedwithNb5+andMg2+(2003:A123Co.)J.Barker,M.Y.Saidi,J.L.Swoyer,Electrochem.Solid-StateLett.,2003,6:A53-A55--------Carbonreductionmethod(ValenceCo.)Carboncoatingof

LiFePO4CoatedwithcarbonObtainedbydecompositionoforganiccompoundsSchematicviewofthecarboncoatingincompositematerialspreparedby(a):addingcarbonblack,(b):addingsugar.CarbonisdepictedasblackandLiFePO4aswhiteChenZH,DahnJR.J.Eelectrochem.Soc.,2002,149(9):A1184abLowerthecontentofactivematerialsincathode;Reducethetapdensityofthecathode;Influencevolumeenergydensityofthecathode;NoimprovementinconductivityforthecoreofLiFePO4particles.ShortcomingsofcarboncoatingCarbonCoatingof

LiFePO4ImproveConductivitybyMetalGrains

SuchasAu,Ag,CunanoparticlesCroceF,EpifanioAD’,HassounJ,etal.Electrochem.andSolidStateLett.,2002,5(3):A47

ImproveConductivitybyDopingChungSY,BlokingJT,ChiangYM.Nat.Mater.2002,2:123Nano-scaledLiFePO4

Topreparenanosizedparticles(nanowire,nanoplate,nanobar).ImprovediffusionchannelsofLi+ionsNanomaterialsareunfavorableforprocessingofelectrodefilmonAlfoil.Ref.:B.W.Kang,G.Ceder,“Batterymaterialsforultrafastcharginganddischarging”,Nature,458(2009)190.Nano-scaledLiFePO4

Outline2OurStrategy

Toevaluatealternativecathodematerialsforalithium-ionbatteryforthepurposeofEVandHEV’s.Cost,cyclelife,safety,andenergydensity?Capacityandratecapability?Newmaterialsbasedonconventionaloxidestructureswithprovenhighratecapabilities;Newcathodeschemesbasedonconductivepolymerswhichmayserveeitherasself-containedcathodesorasanewconductivebinderinmoreconventionalcompositecathodes;SubstitutionintotheenvironmentallybenignandcosteffectiveLiFePO4toimproveratecapabilities.OBJECTIVESAPPROACHLiFePO4/PolymerCompositeCathodesLiFePO4/PPyCompositeCathode

ToimprovecapacityandratecapabilityofcompositeOxide/C/PTFEcathodesbyreplacinginactiveC+PTFEwithanelectrochemicallyactive,conductivepolymer,e.g.,polypyrrole(PPy)

PPy=

Needanamorphouscarboncoatonoxideparticletoprovideattachmentofoxidetopolymerandelectricalcontactbetweenredoxcoupleofoxideandcurrentcollectorthroughthepolymer.Y.H.Huang,J.B.Goodenough,J.Electrochem.Soc.,2006,153:A2282.Outline3ResultsandDiscussionElectrodepositionofLiFePO4/PPycompositeArflowC.E.R.E.W.E.(100mesh)LiFePO4andpyrroleElectrodepositionCondition(CyclicVoltammogram)Scanrange:0~1.3Vvs.Ag/AgClScanrate:100mVs-1,20cyclesElectrolyte:0.1mol/LLiClO4inacetonitrileElectro-polymerizationbycyclicvoltammogramElectrodepositionofLiFePO4/PPycomposite(C)(D)

A

C

DCyclicvoltammetriccurvefortheelectrodepositionoftheC-LiFePO4/PPycathode

XRDpatternsoftheC-LiFePO4/PPycompositeat(C)theoxidizedpotentialand(D)afterreduction.

PPy(red)-C-LiFePO4at0Vvs.Ag/AgCl

PPy(ox)-FePO4

at1.3VvsAg/AgClSEMimages:LiFePO4,LiFePO4/PPycompositeonsteelmesh,(C,D)magnifiedmicrographofLiFePO4/PPycompositeclosetoonemesh.undopingdoping[Py]n+nqClO4-[Pyq+(ClO4-)q]n+nqe-ElectrodepositionofLiFePO4/PPycompositeElectro-polymerization:Specificationofoptimalratiofor(C-LiFePO4)1-x(PPy)xMaximumcompositecapacitywasobtainedin(C-LiFePO4)1-x(PPy)xwithweightratiox0.2Chargeanddischargecompositecapacityvscyclenumberforthe(C-LiFePO4)1-x(PPy)xLiFePO4/PPyCompositeCathodeEnhancedCapacityandRateCapabilityExperimentalProcedure:Chargeatvariousratesto4.1V,dischargeatC/5.ExperimentalProcedure:ChargeatC/10to4.1V,dischargeatvariousrates.CapacityRate(C-LiFePO4)0.84(PPy)0.16C-LiFePO4/C/PTFEChargeDischargeChargeDischarge2C(30min)135.4(89%)133.5103.3(82%)67.05C(12min)130.4(85%)125.341.1(29%)31.710C(6min)111.8(73%)100.28.7(6%)6.320C(3min)97.1(64%)87.300ElectrodepositionofLiFePO4/PPycompositeElectro-polymerizationbyconsecutivepotentialstepsStudiedparametersbypotentialsteps:1-Oxidationpotential(0.9,1.0,1.1,1.2and1.3VvsAg/AgCl)2-Oxidationtime(3,5and7s)3-NumberofSteps(15,30,45and60)4-Reductionpotential(-0.1,-0.2,-0.3,-0.4and-0.5Vvs.Ag/AgCl)Fixedparametersduringpotentialsteps:1-Reductiontime(3s)2-Electrolytesolution(0.1MLiClO4acetonitrilesolution)3-PyrroleConcentration(0.4M)4-C-LiFePO4concentration(0.02M).5-Electrodedistance(0.8cm)6-Solutionstirring.ElectrodepositionofLiFePO4/PPycompositeElectrodemass(mg.cm-2)%PolymerOxidationTime(s)NºofStepsNºofStepsOxidationTime(s)a)b)Capacity(mAhg-1)OxidationTimeNºofStepsElectrodepositionofLiFePO4/PPycompositePolimerizationpotentialAbsolutevaluesPercentagesrelatedtobiggervaluePolimerizationpotentiala)b)Graphicalviewoftheelectrodecomposition(%ofpolymer),depositedmass(mg.cm-2)andspecificcapacity(mAhg-1)ofcomposites,relatedtothepolymerizationpotential.a)showstheabsolutevaluesandb)representsthepercentagerelatedtothebiggestvalue(6.2mgcm-2,30%ofPPyand154mAhg-1)

LiFePO4/PolymerCompositeCathodeY.H.Huang,J.B.Goodenough,Chem.Mater.,2008,20:7237.Electrodepositionbysimultaneouschemicalpolymerization

LiFePO4/PolymerCompositeCathodeCompositespecificcapacityvscyclenumberforLFP/7%PPycompositecathodepreparedwithsimultaneouschemicalpolymerization.

CellvoltageasafunctionofcompositespecificcapacityforLFP/polymercompositecathodes.LiFePO4/PolymerCompositeCathodeChargeat0.1C,dischargeat0.1-20C;Chargeat0.1-20C,dischargeat0.1C;Chargeat0.1-20C,dischargeat0.1-20C.Chargeat0.120C,dischargeat0.1C(Chargedupto94%in10min)Y.H.Huang,J.B.Goodenough,Chem.Mater.,2008,20:7237.Electrodepositionbysimultaneouschemicalpolymerization

Carbon-freeNano-LiFePO4Feature：(1)Carbonfree;(2)Highcapacity;(3)Goodratecapability;(4)Longcyclability;(5)Lowcost.NewElectrolyteLiFSILiFSIStrctureLiFSIadvantages:

Highthermalstability:betterthanLiPF6,decomposition150C;

HighelectronicconductivityandLi+diffusion:

3timeslargerthanLiPF6.

Highlow-temperatureconductivity:

1mScm-1at-50C.Cansolvelow-temperaturebottleneckofhigh-powerLibatteriesforEV/HEVs?Lithiumbis(fluorosulfonimide):Li[N(SO2F)2],whitepowderContent:99.5%;Impurity:Cl-

5ppm。Prof.ZhibinZhou(周志彬),CollaboratedwithProf.M.ArmandOutline4ConclusionsandProspectsCONCLUSIONSAremarkableimprovementintheratecapabilityandcapacityofcathodesusingLiFePO4byreplacingthecarbonplusTeflonadditiveswithpolypyrrole(PPy)bondedtotheoxideparticlesbythecarboncoat.Attachingaconductivepolymertoanactiveoxideparticleisageneralstrategythatalsopromisestoenhancetheratecapabilityofothercathodecomposites.Thevoltagerangeoftheredoxcoupleofthepolymermustoverlapthatoftheactivematerialifthestrategyistowork.Polymer-compositetechniquemaybecomeanefficientwaytoachievecarbon-freeLiFePO4cathodematerialwithcollaborationofnanotechnology.LiFePO4CompositeswithPolymersHigh-PowerLi-ionBatteriesLiFePO4BatteriesforPowerSourcesWhograspsthetechniqueofLiFePO4batteriesinadvance,whowillbecometheleaderofthemarket!PatentOriginalpatent(J.B.Goodenough)Carbon-coatedpatent(2008China)TechniqueQualityisnotstablefordifferentbatch;Lowtemperature;TapdensityMarketIncreasingwithEVs(100,000tons2012)Justbeginning,indevelopingAcknowledgementsK.ZaghibandN.Ravet(Canada)I.BoyanoaandI.deMeatza(Spain)forcollaborationThankyouforyourattention！LiFePO4CompositeswithPolymers《化妆品术语》起草情况汇报中国疾病预防控制中心环境与健康相关产品安全所一、标准的立项和下达时间2006年卫生部政法司要求各标委会都要建立自己的术语标准。1ONE二、标准经费标准研制经费：3.8万三、标准的立项意义术语标准有利于行业间技术交流、提高标准一致性、消除贸易误差，作为标准体系中的基础标准，术语标准在各个领域的标准体系中均起着重要的作用。随着我国化妆品卫生标准体系建设逐步加快，所涉及的术语和定义的数量也在迅速增长，在此情形下，化妆品术语标准的制定就显得尤为重要。四、标准的制订原则1.合法性遵守《化妆品卫生监督条例》、《化妆品卫生监督条例实施细则》中关于化妆品的定义。2.协调性直接引用或修改采用的方式，与相关标准中的术语和定义相协调。3.科学性对于没有国标或定义不统一的术语，在定义时体现科学性的原则。4.实用性在标准体系中出现频率较高，与行业联系较紧密的术语优先选用。五、标准的起草经过

第一阶段：资料搜集

搜集国内外相关法规、标准、文献并对国外文献如美国21CFR进行翻译。第二阶段：2007年末形成初稿

初稿内容包括一般术语、卫生化学术语、毒理学术语、微生物术语、产品术语、人体安全和功效评价术语，常用英文成份术语等７部分。第三阶段：专家统稿1.2007年12月第一次专家统稿会（修订情况：1.在结构上增加原料功能术语、相关国际组织和科研机构等内容；2.在内容上增加一般术语、产品术语的种类，将化妆品行业的新产品类别纳入本标准；3.对于毒理学、卫生化学、微生物学术语进行修改；4.删除与化妆品联系不紧密、无存在必要的常用英文成分术语。2.2009年1月第二次专家统稿会会议意见：1.修改能引用国家标准的尽量引用国家标准；对存在歧义的个别用词进行修改。2.删除由于本标准中的“产品术语”一章和香化协会所制定的某个标准存在重复，因此删除“产品术语”一章的内容；对“原料功能术语”的内容进行梳理，删除了20余条内容。3.增加专家建议增加“化妆品限用物质”等若干项术语。第四