高比能锂离子电池合金负极材料研究.ppt

1高比能二次锂离子电池合金负极材料的研究及其规模化制备(No.2019AA03Z231)2不同二次电池的性能对比SystemNi-CdNi-MHLi-IonEnvironmentalProblemSevereModerateModerate(tendtofriendly)VoltageofBattery（V）1.21.23.6VolumetricEnergyDensity(Wh/L)125165270MassEnergyDensity(Wh/kg)4060105CyclingLife(N)5005001200Self-dischargeLoss(%/month)25-3030-406-123Applicationinmicroelectronics4碳材料为目前锂离子电池常用的负极材料碳材料的理论比容量为372mAh/g目前碳负极材料的实际比容量已经非常接近其理论比容量需要寻找新的、可以替代碳材料的高容量锂离子电池负极材料Sn基合金材料引起了人们的极大关注它的理论比容量为：Li22Sn5:994mAh/g•人们研究了许多Sn基合金体系,如:SnSb,SnCu,SnCo,SnV,SnFe,etc.5•阻碍Sn基合金商业化的原因•电极大的体积膨胀–采用纳米颗粒的合金粉体•首次不可逆容量较高(低的首次库仑效率)•Newidea•具有纳/微复合结构和内微孔的颗粒SnCopowders6•传统的合成方法–从水溶液中的化学共沉淀–粉末冶金–电镀的方法–机械合金化的方法这些合成方法要么工艺复杂，要么不适宜大规模生产7Carbothermalreduction•Simple,cheapandmassproductionSnO2+2C=Sn+2CO(g)Sb2O3+3C=2Sb+3CO(g)CuO+C=Cu+CO(g)NiO+C=Ni+CO(g)CoO+C=Co+CO(g)SynthesisofSn-basedAlloyCompositePowder02004006008001000-80-60-40-20020406080100120G(kJ)Temp.(0C)SnO2+2C=Sn(l)+2CO6300C802004006008001000-120-100-80-60-40-200204060801004350CG(kJ)Temp.(0C)NiO+C=Ni+CO(g)-20002004006008001000-200-150-100-50050-250CG(kJ)Temp.(0C)CuO+C=Cu+CO(g)02004006008001000-300-250-200-150-100-500501001502002504350CG(kJ)Temp.(0C)Sb2O3+3C=2Sb+3CO(g)02004006008001000-100-80-60-40-200204060801005000CG(kJ)Temp.(0C)CoO+C=Co+CO(g)Thermodynamiccalculationforcarbothermalreductionofmetaloxides9FlowchartOxidesCarbonMixingFiringSievingTapecastingAssemblingcellXRDSEM,TEMBETCharge/dischargecyclingCyclicvoltammogramsACimpedance10Sn-Sbsystem020406080100Intensity(a.u.)2(degree)SnSb850℃,2h850℃,6hTEMforsingleparticle11SEMmorphologiesofSnSballoypowders2h4h6h8h12Sn-Sbsystem05101520020040060080010001200Capacity(mAh/g)Cyclenumber(n)2h6h50mA/g100mA/g200mA/g0510152002004006008001000Capacity(mAh/g)Cyclenumber(n)2h6hMarioWachtler,J.PowerSources105(2019):151-16013Sn-Sbsystem14Sn-Sbsystem0510152001002003004005006007008009001000SpecificCapacity(mAh/g)Cyclenumber(n)0.3-1.2V0.01-0.8V体积比容量是碳负极的2倍。02004006008001000-0.20.00.20.40.60.81.01.21.41.61.8Voltage/Vvs.Li+/LiSpecificcapacity/mAhg-115Sn-Nisystem1020304050607080050010001500200025003000350033333333333222111111111Intensity(a.u.)2(degree)1Sn65-02962Ni3Sn206-04143Ni3Sn404-0845116Sn-NisystemZ.P.Guo,Z.W.Zhao,H.K.Liu,S.X.Dou,Carbon43(2019)1392CyclingperformanceofNiSn2alloycompositeelectrodeatconstantcurrentdensityof100mAg-102468101214161820222426050100150200250300350400450Specificcapacity/mAhg-1Cyclenumber/nChargeDischarge17Sn-Sb-Nisystem024681012141618200100200300400500600Cyclenumber/nDischargecapacity/mAhg-1100mAg-1150mAg-1200mAg-1900℃,2hCyclingperformance18Sn-Cosystem020406080100050010001500200025003000Intensity(a.u.)2(degree)SnCo024681012141618200100200300400500600700800900Dischargecapacity/mAhg-1Cyclenumber/n50mAg-1500mAg-1C.Mi,etal,J.InorganicChemistry,3(2019)283.800℃,2h19Sn-Cu-Cosystem20Sn-Cu-Cosystem05101520-1000100200300400500600700800Capacity(mAh/g)Cyclenumber(n)Sn5/3CuCoSn3CuCoSn4CuCo0510152025-1000100200300400500600700800Capacity(mAh/g)Cyclenumber(n)0.01-0.7V0.01-1.5V21Sn-Co-C0246810121416182022242628300100200300400500600(a)Capacity/mAhg-1CyclenumberCoSn2chargeCoSn2dischargeCoSn2CchargeCoSn2CdischargeCoSn2C10chargeCoSn2C10discharge22Si-基负极材料的研究051015202530354001000200030004000SpecificCapcity(mAh/g)CycleNumber(n)delithiationlithiationCut-off：0.01-3.0VCurrent-density：250mA/g23Si-基负极材料的研究010203040500200400600800100012001400160018002000SpecificCapcity(mAh/g)Cyclenumber(n)lithiationdelithiatioin24致谢感谢国家“863”高技术发展计划对本项目的支持(No.2019AA03Z231).25