鋰離子電池中的安全問題

1、Safety Issues In Lithium Ion Battery(LIB)Your Site HereCOMPANYCOMPANYLOGOLOGOYOUR SITE HEREOur Group鋰離子鋰離子電池電池郭玉強(qiáng)郭玉強(qiáng)呂曉奇呂曉奇錢曉東錢曉東江賽華江賽華洪寧寧洪寧寧YOUR SITE HEREContentsWhat We Can Do4Introduction To LIB1Synthesis Method2Problems in LIB3Forecast5YOUR SITE HEREYOUR SITE HEREYOUR SITE HEREHigh work potential

2、 High energy densityHigh capacity Long cycle lifeWeak self-discharge rateNo remembering effectClean energyYOUR SITE HERE 1.1 Structure-YOUR SITE HERECATHODELiCoO2LiNiO2LiMnO4Li1-xMn2-yMyO4Li1-xCo1-yMyO2Li1-xNi1-y-zCoyMzO4LixFePO4, Li1-xVOPO4Salt: LiPF6,LiBF4Solvent: PC,DEC.DMC,MECSEI forming improve

3、r: VCFlame retardant: DMMP, ATFECOvercharge- protector:Ionic salvation enhancerAbove composites + Polymer network CarbonSnO basedComposite alloy3d-metal oxideNitrideELECTROLYTEANODE-compositionGraphite, carbon fiber, MCMBSoft carbon, hard carbonDoped carbonSEISEI3.7eVSeparatorYOUR SITE HERE1.2 Work

4、PrincipleYOUR SITE HEREDuring work progress, Li is reversibly intercalated into and de-intercalated from anode/cathode because of which LIB is called rocking Chair Batteries. YOUR SITE HERE1.3 Preparation processYOUR SITE HERE1.4 Research progressYOUR SITE HERE1.5 Relative test（1 1）CVCV循環(huán)伏安測(cè)試循環(huán)伏安測(cè)試

5、（2 2）EISEIS交流阻抗測(cè)試交流阻抗測(cè)試 （3 3）ETET電壓電壓- -時(shí)間變化時(shí)間變化 （4 4）電導(dǎo)率測(cè)試）電導(dǎo)率測(cè)試 （5 5）恒流恒壓充放電測(cè)試）恒流恒壓充放電測(cè)試 （6 6）燃燒試驗(yàn)臺(tái)）燃燒試驗(yàn)臺(tái) （7 7）C80C80微量量熱儀微量量熱儀 （8 8）熱重分析儀）熱重分析儀 YOUR SITE HEREContentsWhat We Can Do4Introduction To LIB1Synthesis Method2Problems in LIB3Forecast5YOUR SITE HERECo-precipitation80 vol.% H2OAdjusted pH

6、with NH4OH NaOH solutionHot H2ONiSO46H2O, CoSO47H2O,MnSO4H2OCathodeYOUR SITE HERENi0.80Co0.15Mn0.05(OH)2LiOHH2O (molar ratio of 1.02）Muffle furnace for 12h at 650-900LiNi0.80Co0.15Mn0.05O2YOUR SITE HERENH3:metal molar ratio of 1.0 after 24 h precipitation at different pH ranges: (a) 9.510.0, (b) 11.

7、211.3,(c) 11.511.6 and (d) 11.912.0 SEM images of LiNi0.80Co0.15Mn0.05O2 after calcining at different temperatures: (a) 750 C, (b) 800 C, (c) 850 C and (d) 900 CSEM images of LiNi0.80Co0.15Mn0.05O2 after sintering at different conditionspH range 11.511.6 and different NH3:metal molar ratios: (a) 0.6

8、, (b) 0.8, (c) 1.0, and (d) 1.2magnification: I = 500 and II = 10,000).YOUR SITE HERE FeSO47H2O: H3PO4: LiOH =1:1:3 加入到加入到CTAB水溶液中，水溶液中， pH ranged between 7.2 and 7.5，35 C劇烈攪拌劇烈攪拌30min后移入內(nèi)襯后移入內(nèi)襯Teflon的反應(yīng)釜中，在的反應(yīng)釜中，在120 C加熱爐中下保持加熱爐中下保持5小小時(shí)，冷卻至室溫后將綠色沉淀物洗滌除去表面活性劑時(shí)，冷卻至室溫后將綠色沉淀物洗滌除去表面活性劑等雜質(zhì)并于等雜質(zhì)并于 40 C干燥，

9、然后在高純氮中熱處理干燥，然后在高純氮中熱處理（200 C預(yù)處理，預(yù)處理，600 C處理處理12h)。Hydrothermal synthesisYOUR SITE HERECH3CO2Li2H2OFeCl24H2OP2O5SolutionEthanolEthanolEthanolStirred for 3 hSolEthanol was evaporated under continuousflow of ultra high purity Ar.GelUnder H2/Ar = 10%/90% atmosphere at 500 C for 5 hPowderOlivine-type Li

10、FePO4Lauric acidSol-GelYOUR SITE HEREThe SEM micrographs of LiFePO4 powders synthesized (a) without and (b) with lauric acid after heat-treatment of the precursor at 500 C under10H290Ar atmosphere.YOUR SITE HERESolution combustion methodlithium nitrate, nickel nitrate cobalt nitrate manganese acetat

11、eThe fuel HMTAmuffle furnaceLiNi1/3Co1/3Mn1/3O2Calcined at 900distilled waterHeating 400J Solid State Electrochem (2010) 14:1726 DOI 10.1007/s10008-008-0772-3YOUR SITE HEREextrudingannealingstretchingMicropores filmseparatorYOUR SITE HEREContentsWhat We Can Do4Introduction To LIB1Synthesis Method2Pr

12、oblems in LIB3Forecast5YOUR SITE HERE事故事故原因原因表征表征關(guān)于鋰電池關(guān)于鋰電池爆炸安全事爆炸安全事故問題屢見故問題屢見不鮮不鮮活性電極及易活性電極及易燃電解液在過燃電解液在過充放電過熱等充放電過熱等時(shí)發(fā)生復(fù)雜反時(shí)發(fā)生復(fù)雜反應(yīng)，引起火災(zāi)應(yīng)，引起火災(zāi)鏈?zhǔn)绞Э責(zé)釘U(kuò)鏈?zhǔn)绞Э責(zé)釘U(kuò)散散改進(jìn)聚合物改進(jìn)聚合物燃燒測(cè)試方：燃燒測(cè)試方：LOI,TG&DSC,SET3.1 Thermal SafetyYOUR SITE HERE3.1.2 Thermal safety鏈?zhǔn)椒磻?yīng)可燃物點(diǎn)火源氧化劑燃燒三要素YOUR SITE HEREthermal decomposition o

13、f the electrolytereduction of the electrolyte by the anodeoxidation of the electrolyte by the cathodethermal Decomposition of the anode and cathodemelting of the separator and the consequent internal short fireoverchargingshort circuitingcrushingYOUR SITE HEREYOUR SITE HERE3.1.3 Characterization-LOI

14、所謂所謂極限氧指數(shù)極限氧指數(shù)，就是指在規(guī)定的試驗(yàn)條件下，材，就是指在規(guī)定的試驗(yàn)條件下，材料在氧氮混合氣體中剛好能保持燃燒狀態(tài)所需的料在氧氮混合氣體中剛好能保持燃燒狀態(tài)所需的最低氧氣。極限氧指數(shù)越高，表明材料越不易燃。最低氧氣。極限氧指數(shù)越高，表明材料越不易燃。對(duì)于鋰離子電池的電解液，測(cè)試的方法是：采用直對(duì)于鋰離子電池的電解液，測(cè)試的方法是：采用直徑一定的特定玻璃纖維，浸泡約徑一定的特定玻璃纖維，浸泡約1.0g的電解液，的電解液，然后再進(jìn)行常規(guī)的氧指數(shù)測(cè)試。然后再進(jìn)行常規(guī)的氧指數(shù)測(cè)試。YOUR SITE HERE3.1.3 Characterization-TG&DSCYOUR SITE HER

15、E3.1.3 Characterization: FT-IR40003500300025002000150010005001250-1260cm-11460cm-11044cm-1950cm-11019cm-1800cm-1650cm-13450cm-11150cm-11730cm-12960cm-1 550oC440oC420oC400oC350oC300oC280oC260oC200oC100oCRTTransmissionWavenumber (cm-1)YOUR SITE HERE3.1.3 Characterization-SETYOUR SITE HERE3.2.1 CV(循環(huán)伏安

16、曲線循環(huán)伏安曲線)3.2 Electronic performanceYOUR SITE HERE3.2.2 P-C&C-C（電池循環(huán)性能曲線）（電池循環(huán)性能曲線）YOUR SITE HERE3.2.3 EIS(電化學(xué)阻抗電化學(xué)阻抗)YOUR SITE HERE3.2.4 C-T電導(dǎo)率曲線電導(dǎo)率曲線YOUR SITE HEREContentsWhat We Can Do4Introduction To LIB1Synthesis Method2Problems in LIB3Forecast5YOUR SITE HERESafety vents-Thermal fuses-Other circ

17、uit breakers-open in response to a sudden increase in cell pressure, allowing gases to escapethe one shot fuse which is a wire of a fusible alloy with resistance and thermal characteristics that allow it to melt when a pre-set current flows through itmagnetic switches, bimetallic thermostats and ele

18、ctronic protection circuit modules : protect power packs and to monitor their temperatureFactors play a role in the operation of the devices that involve limiting the current passing through them 4.1 Conventional safety devicesYOUR SITE HERESeparators for lithium-ion batteries are polyolefin micropo

19、rous films such as PE,PP,or their drawers.If the cell temperature rises abnormally because of an excessive overcharge, for example, the heat generated softens PE and closes the micropores in the film, thus ionic transport between the electrodes is effectively stopped and current ceases to flow. 4.2

20、Shutdown separatorsYOUR SITE HERECeramic PTC materialsoperate under high voltages and can return to their normal resistancemode with great accuracyConductive-polymer PTC devicesAt elevated temperatures, the polymers structure changes to an amorphous state. The accompanying expansion of the matrix br

21、eaks the conductive pathway between the embedded particles, rapidly increasing the devices resistance by several ordersEmerged safety devices called positive temperature coefficient devices based on materials whose resistance increases dramatically with a rise in temperature4.3 Self-resetting devicesYOUR SITE HEREphysical char-forming processchemical radical scavenging processFluorinated compoundsorganophosphorus compoundsMain components of SEI: decomposed products of electrolyteScheme 1&2&