磷酸铁锂动力电池的高低温性能解决途径.

1、UniversityApproaches to improve the electrochemicalperformance of LiFePO4-based lithium ionbatteries working in a wide temperature range磷酸铁锂动力电池的高低温性能解决途径Zi-Feng MaDepartment of Chemical EngineeringShanghai Jiao Tong University,Shanghai 200240, ChinaEmail: zfmaIntroduction前期工作基础:上海交通大学在LiFePO4正极材料制备

2、新工艺方面，获得6项中国发明专利（专利号:ZL 200410018476.4等）；2004年开始与浙江横店东磁股份有限公司合作开展产业 化技术开发，获得2006年浙江省产业化转化项目，2008年初完成中试线。Mechanical chemical reactionFe+2FePO4+U3PO4.0.5H2O -*3LiFePO4 + 0.5H2O Xiao-Zhen Liao. Zi-Fcng Ma*, Liang Wang, Xiao-Ming Zhang, Yi Jiang, Yu-Shi He, Electrochem. Solid-State Lett. 2004, 7(12)： A5

3、22-525 (SCI Cited 33) Xiao-Zhen Liao, Zi-Feng Maj Yu-Shi He, Xia Zhanj9 Lian* Wang, Journal of the Electrochemical Society. 2005, 152(10):A1969-1972 (SCI cited 25) 200X年全国优秀博士学位论文提名奖：2007年上海市优秀博士学位论文Unkveralty再分级处理现有生产能力：年产150吨磷酸铁锂正极材料 近期目标：合资建立磷酸铁锂动力电池生产线IntroductionIn winter, the electric vehicle

4、have to be started at low temperature and the battery need to keep better performanceIntroductionApproaches to enhance the performance of LiFePO4/C cathode at low temperatureCathode: particle size minimization or dopingElectrolyte:Solvent selection: affects liquid temperature range and viscosity, an

5、d participating in the formation of a solid electrolyte interface (SEI), the resistance of which is main resistance in the full czll(两元.三元或四元) Lithium salt: LiPF6, LiBF4, LiBOB et alK. Amine9 J. Lili, I. Belharouak, Electrochein. Commiin. 7 (2005) 669.LiFePO4/C低温性能研究L()m(0.9LiBF4-()JLiBOB) 1:1:3 PC/

6、EC/EMC electrolyte/vgfso-O- x13Capacity / mAh g1r20406080Capacity / mAh g1Discharge curves of Li/LiFePO4 cell with a 1.0m(0.9UBF4-0.1UBOB) 1:1:3 PC/EC/EMC electrolyte, which were recorded at 1C by charging the cell at 20 C and then discharging at a specific temperatureEffect of salt ratio on the dis

7、charge voltage of Li/LiFePO4 cells, which was measured at 1C by charging the cell at 20 C and then discharging at -30 “C.S.S.Zhang9 K.Xi“ T.R.Jow J Power Sources 159(2006) 702-707LiFePO4/C低温性能研究leOM LiPFe/EC+DMC+DEC+EMCv/v) electrolyte020406080100120140Capacity / mAh/gn、n .5 / gsoAn.n s O6el-OA02040

8、6080100120140160Capacity / mAh/gWe studied the low temperature performanee of LiFePO/C cathode in a quaternary carbonate-based electrolyte The discharge capacities of the LiFePO/C cathode were about 134.5 mAh/g (20C), 114 mAh/g (0C), 90 mAh/g (-20C) and 69 mAh/g (40C) using a 1C charge-discharge rat

9、e.X.-Z. Liao et al. / Electrochemistry Communications 10 (2008) 691-694UniversityLiFePO4/C低温性能研究uimo/ze-tTOO 200300SOO X只TempRQ)Rp(ft)R)D (cm%)20 C4.6786.968.2I.70X !0120* C5.93101.1124.3l.55XK)n-20 C7.88120.0315.12.05 XIO1340。C13.04126.32005.42.I2XIO*4Re Z / OhmThe improving of the reaction activit

10、y of the electrolyte-active material in terface by surface modification and electrolyte optimization, increasing the lithium diffusion abilityUniversityLiFePO4/C高温性能研究Three solutions to enhance the cycling performance of LiFePO4/C cathode working at high temperature It is based on similar reason tha

11、t is to prevent Fe( II) ions dissolving. Electrolyte Anode CathodeJiao Tong UniversityElectrolyte Design1-2M LiPF6/ EC+PC+DMC (1:1:3) electrolyte0.7M LiBOB/ EC+PC+DMC (1:1:3) electrolyteFig. 9. Amount of Fc* ions dissolved from C-LiFcPO4 powder that lusbeenagedin I2M LiPFCPC DMC U:l:3)and 0.7 M LiBO

12、B/ tC:PC DMC (1:1:3) for one week al 55 CEaa wuo。丄0.0-1 1.204060Cyde Number80 100Eig. & Cycling pcrfbnuance of C-LiFePOyLuTisO:： cell al 55 C usinu 1.2 M LiPF. ECfPC/DMC (I 1:3) dectrolvtc.2 0 8 6 4 2 1.1.O Q a o 66 woBdB。poNaEJONK.Amine9 J.Liu, I.BeUiarouak, Electrochem. Commun. 7(2005)669-673Jiao

13、Tong University1.0m(0.9LiBF4-(h 1 LiBOB) 1:1:3 PC/EC/EMC electrolytel6 ll#OA【代对LiFePO4结构的影响f a6e_o包覆后的倍率性能从8C 提高到40C,放电平台髙Cycle performance of PPy LiFePO4/C composite at different temperatures1.5020406080100120140160Capacity (mAh/g)20C 15C 8C5C 2C1CRate capabilities of LiFePO4/C and PPy- LiFePO4/C e

14、lectrodes (active material : carbon black: PVDF=75:15:10)100200300400500Cycle numberPPy coating LiFePO4/C cathodeDischarge curves of LiFePO4/C and PPy-LiFePO4/Ccomposite cathode materials at 5C working in 55C20406080100120140160Capacity (mAh/g)64208642083.3.3.3.222221.n4n .5 &2-020204060801001201401

15、60180Capacity (mAtVg)PPy 丄 iFePO/CLiFePO/CUniversityPPy coating LiFePO4/C cathode LiFcPO4/C-PPy LiFePO4/CCycling performance of the Li-LiFePO4/C cell at 5；C ?如恨clFchrge rat# at 5匸 )100200300400500600Cycle numbles170 r160 kThe discharge curves of the cathodes at different cycles.150140130120110100908

16、070605040302010Yang Kz/ig, Xiao-Zhen Liao, Zi-Feng Ma, Bao-Feng Wang, Yu-Shi He9 Li He Electrochem. Comnuui. 11(2009)1277-1280UniversitySummarySeveral approaches can be used to enhance the cycling performance of LiFePO4/C cathode working in a wide temperature range. The new electrolytes design and p

17、reparation are mostly significant to improve the low temperature performance.Thus improving the reaction activity of the electrolyte-active material interface by surface modification and electrolyte optimization, increasing the lithium diffusion ability by modifying the crystal structure and minimiz

18、ing the particle size are considered to be effective approaches to improve the low temperature performance of LiFePO4/C cathode material.Anode coating is effective to improve the cycling performance of the LiFePO4/C based lithium ion batteries*UniversityAck no wledgment 973 Program of China (2007CB209705) Natural Science Foundation of China (20773087) Natural Science Foundation of Shanghai (07JC14024).Ws for pUniversity忙虬 如娅UhdKTZj凹kJWelcome to Shanghai 2010 EXPO8th International Symposium on New Materials and Nano-Ma