InnovationforApplication,ProgresswithintegrityTheCurrentStatusandDevelopmentofElectrolyteAdditivesForLithiumIonBatteries郑洪河苏州大学能源学院SchoolofEnergy,SoochowUniversity,China第九届国际储能大会交流报告1234ResearchbackgroundAdjustingsolutionstructureFluoranatedadditivesS-basedelectrolyteadditives5ConclusionOutline2017国内锂离子电池电解液市场近200亿元，添加剂市场超15亿元电动汽车的发展将带动锂离子迅速发展和电解液技术的巨大进步,更多新型配方和添加剂投入实际应用高电压、高能量密度锂离子电池、功率型电池、高低温电池、高安全电池等1.Background纵观电池的发展历史，电解液的革新对电池科学发展的贡献绝不亚于任何一种电极材料，例如锌锰电池自诞生以来经历了三次革命，其中两次革命源于电解液组成的变化，分别是从第二代NH4Cl为主的电解液到第三代的ZnCl2为主的电解液，再到第四代的KOH溶液为主的碱锰电池，由于电解液组成的变化，电池的反应机理和成流机制也发生了明显的变化。KOHTheimportanceofbatteryelectrolyteZn+2MnO2+2NH4Cl2MnOOH+Zn(NH3)2Cl24Zn+8MnO2+9H2O+ZnCl28MnOOH+ZnCl2·4ZnO·5H2OZn+2MnO2+2H2O2MnOOH+Zn(OH)2ThedevelopmentandrevolutionofLIBelectrolyte•类似地，锂离子电池的电解液技术也已经经历了3次变革，电解质的多样性也为锂离子电池多样化做出了实质性的贡献，人们常根据电解质的类型把锂离子电池分为液体锂离子电池、聚合物锂离子电池和全固态锂离子电池，并用以满足不同的生产和生活实践。当然，由于液体电解质特殊的优势，在未来相当长的一个时期，液体锂离子电池仍将主导锂离子电池市场。PC+DMEPC+DMCPC+DECEC+DMCEC+DECEC+DMCEC+EMCfunctionaladditiveslithiumbatterybasedonLimetallithiumionbattery(1stgenerationbasedonCOKEanode)lithiumionbattery(2ndgenerationwithgraphiteanode)当然，由于液体电解质特殊的优势，在未来相当长的一个时期，液体锂离子电池仍将主导锂离子电池市场。TheroleofelectrolytesinlithiumionbatterieslReversiblecapacitylRatecapabilitylOperatingtemperaturelSafetylShelflifelSelf-dischargepropertieslCyclelifeElectrolyteisthebridgeconnectingcathodeandanode,themediaforLitransportation,theplacewheresidereactionoccursConfifentialMaterials•Performance,calendar-life,andsafetycharacteristicsofLi-ioncellsaredictatedbythenatureandstabilityoftheelectrolyteandtheelectrode-electrolyteinterfaces.•Thegoalistodevelopnovelelectrolyteswiththefollowingcharacteristics:–Wideelectrochemicalstabilitywindow,0to>5V–Widetemperaturestabilityrange,-30to+80°C–Non-reactivitywithothercellcomponents–Excellentionicconductivitytoenablerapidiontransport–Stabilityforover5000deep-dischargecycles–Stabilityoverthe10yrsbatterylifeObjectiveforelectrolytedevelopment1.BackgroundElectrolyteadditivesplayacrucialrolefororganicelectrolytesystems1.Background1AdjustingsolutionstructureThelineontherightofthenegativechargesrepresentstheinnerHelmholtzplane(IHP).ThedashedlinesdepictstheouterHelmholtzplane(OHP)andthedottedlineillustratestheplaneofelectrokineticcharge,ortheshearplane(SP).阴离子竞争性溶剂化改变溶剂化结构76074072070068002000400060008000IntensitypurePCsolventLiTFSI/PCLiTFSI/PC:NMA(2.5:1)Wavenumber/cm-1Li+-PCinteraction10002000300040000123AbsorptivityWavenumber/cm-1PC:NMA(2.5:1)DMC:NMA(1:1)PC01002003004005006007000.00.40.81.21.62.0Potential/VSpecificcapacity/mAhg-1EC:PC(1:1)EC:PC(1:1)+NMA(5%)electrolytedecomposition阳离子竞争性溶剂化对电解液性能的调控LiionPCmoleculecompetationion01002003004005006000.00.51.01.52.0Voltage/VCapacity/(mAh/g)ionicliquidregulation4006008001000120014001600180020000.750.800.850.900.951.001.051.101.151.201.251.30IntensityWaveNumber/cm-10.05电解液中纳米团簇结构取向和溶剂化数调整AB2.Fluoranatedadditives•fluorosolventsislessflammable–SolventwithaFtoHratio>4appearstohaveimprovedthermalproperties.Inthewicktesttheelectrolytecontainingthefluorosolventdidn’tcatchfire.•Fluorosolventsinconjunctionwithcycliccarbonatesshouldexhibitimprovedthermalproperties–Lowtemperatureperformancemaysuffer•Fluoro-ECmaybeanalternative•Fluoroether:isusedasco-solventtoimproveoxidationpotentialinHatachi.氟代碳酸酯类添加剂的成膜与钝化(a)(b)(c)(d)(e)(f)该添加剂对负极表面膜结构和性能的影响添加剂在整体电池中的作用,发展具有同时优化正极和负极表面的新型添加剂对电池产业的发展具有特别重要的意义,特别是发展高低温电池和长寿命电池非常重要.SOOOOSOOOOSOOOOOOSOO环状磺酸酯系列别名：DTDPCSPEGLSTTS外观：白色固体（部分为液体）含量：≥99.5%（GC）水分：≤200PPM已经成为当前成膜添加剂的主流，特别在三元和磷酸铁锂电池中具有重要的意义3.S-basedelectrolyteadditivesForexample•Controlelectrolyte：EC/DMC/EMC(1:1:1)1.0MLiPF6EC/FEC/DMC/EMC(1:1:3:1)1.0/1.2MLiPF6•Additives：FEC5%+VC5%LiODFB5%DTD1%+MMDS1%LiTFSI5%PC5%DTD1%TFPC5%BS1%LiBOB1%+MMDS1%PST1%LiPOF21%+DTD1%DTD1%+LiTFSI5%DTD1%+LiDOFB5%VC5%+DTD1%+LiTFSI5%BS1%+LiDOFB5%PST1%+LiDOFB5%HongheZhenget.al.TraditionaladditivecombinedwithdifferentsulfonateadditivesincludingBS,PST,DTD,MMDSetc.050100150200020406080100120140SpecificCapacity(mAh/g)CycleNumber1131-1.01.0-LiODFB5%1.0-LiTFSI5%1.0-DTD1%1.0-BS1%1.0-PST1%1.0-DTD1%-LiTFSI5%1.0-DTD1%-LiODFB5%1.0-BS1%-LiODFB5%1.0-PST1%-LiODFB5%1.0-VC5%-DTD1%-LiTFSI5%PSTandBSplayaexcellentroleextendingthecyclelifeHongheZhenget.al.050100150200020406080100120140SpecificCapacity(mAh/g)CycleNumber1131-1.21.2-LiODFB5%1.2-LiTFSI5%1.2-DTD1%1.2-BS1%1.2-PST1%1.2-DTD1%-LiTFSI5%1.2-DTD1%-LiODFB5%1.2-BS1%-LiODFB5%1.2-PST1%-LiODFB5%1.2-VC5%-DTD1%-LiTFSI5%PSTandBSplayaexcellentroleextendingthecyclelifeHongheZhenget.al.4.Sibasedelectrolyteadditive这是一类新的系统，具有新型官能团的硅烷添加剂，在改善硅负极性能方面取得了一些进展OSiSiO样品C-CD-CFESE03116.4410076.0194.3012037.9271475.0893.9423140.73996.478.5995.0333192.14061.778.599542805.7369375.9793.8352048.62802.873.0994.51硅烷添加剂用于硅负极的研究SiOOSi硅烷添加剂用于硅负极的研究引入双键希望增强电极表面的成膜性质稳定硅表面SamplesD-CC-CF-ES-ES0032131.52798.476.1794.04S0031974.22634.374.9492.731%29703812.377.996.812%3212.7407578.8494.863%3204.54033.679.4495.554%3752.6467480.2894.655%2435309979.5494.47硅烷添加剂用于硅负极的研究1%2%3%4%5%0%首效：91.71%二次：96.65%首效：90.19%二次：95.93%首效：91.03%二次：95.76%首效：89.80%二次：96.32%首效：89.94%二次：95.47%首效：89.34%二次：96.22%硅烷添加剂用于硅负极的研究引入氟希望增强电极表面的成膜性质稳定硅表面添加剂体积比%电池首次放电比容量（mAh/g）首次充电比容量（mAh/g）首次效率（%）第二圈效率（%）0%电池13128.22918.591.7196.65电池22741.62486.790.7096.211%电池13135.32827.790.1995.93电池21626.51417.687.1595.222%电池13477.03165.391.0395.76电池23817.63458.590.5996.003%电池12806.52520.289.8096.32电池22806.52520.286.7594.734%电池13427.13082.389.9495.47电池23408.33068.990.0495.895%电池13696.13302.189.3496.22电池2981.4787.380.2391.56硅烷添加剂用于硅负极的研究这类添加剂在效率和容量方面也没有表现出明显的优势硅电极的长期循环性能有一定提升，但提升效果不显著四氟硅烷基添加剂不同浓度首次放电比容量首次充电比容量首次效率（%）0%3318.82745.682.731%1974.31563.979.212%2653.42141.380.703%3166.12521.179.634%2051.51596.877.845%2445.51865.276.27硅烷添加剂用于硅负极的研究硅烷氟代以后不能显著改善硅基负极的性能导致首次效率和可逆容量的下降，循环性能也没有明显改善不同电解液添加剂对硅负极性能的影响电解液添加剂的选择对硅负极具有特别重要的意义2019-4-2828磺酸酯类添加剂用于硅负极的研究电解液添加剂对硅碳复合电极的影响.结果非常令人乐观2019-4-2829磺酸酯类添加剂用于硅负极的研究4.4磷基添加剂5.Conclusions•Novelelectrolytesneedtobedevelopedtomeetthecost,calendarlifeandsafetyrequirementsofbatteriesforEVandHEVapplications.•Therearealotoffundamentalissuesfortheetrolytesystemsinlithiumioncells.•Electrolyteoptimizationneedtobecombinedwithcelltechnologies•All-solidcellsstillhavealongwaytogoandthetransitionstageistheadvancedgelelectrolyte32感谢国家自然科学基金和国家科技部重大研发计划的支持！谢谢课题组曲群婷、王艳、石强、衡帅、绍杰、朱国斌和全体博士，硕士研究生！QUESTIONS:hhzheng@suda.edu.cn