热失控小知识

《热失控小知识》由会员上传分享，免费在线阅读，更多相关内容在应用文档-天天文库。

1、11.13.20171.ThehighgravimetricandvolumetricenergydensitiesofLi-ioncellsprovideclearadvantagesoverotherbatterychemistriessuchasNiMHorlead-acid,buttheiractivematerialsandelectrolytesposeongoingsafetychallengesfortheseapplications.锂离子电池的高重量和体积能量密度与其他电池化学品如镍氢电池或铅酸电池

2、相比具有明显的优势，但其活性材料和电解质对这些应用构成持续的安全挑战。2.FrequentincidentswithLi-ionbatteryfireshighlightthesesafetyconcernsinpersonalelectronics,transportationvehicles,andevenlargecommercialaircraft.Toguardagainstsuchaccidents,arobustthermalmanagementsystemisnecessarytoprotecttheb

3、atterypackunderallcircumstances,especiallywhenthemonitoringoractivecoolingsystemfailstodetectacellfailure.频繁发生的锂离子电池事故突显了个人电子，交通车辆甚至大型商用飞机的安全隐患。为防止此类事故发生，在任何情况下都需要强大的热管理系统来保护电池组，特别是在监控或主动冷却系统未能检测到电池故障时。3.TheseLi-ionfireswerecausedbythermalrunaway,achemicalphenom

4、enonduringwhichtheanode,cathode,andelectrolyteirreversiblyreact,generatinglargeamountsofheatthatescalatethecelltemperatureandinternalpressure,oftenwithcombustionofgases.这些锂离子火是由热失控引起的，这种化学现象是阳极，阴极和电解质发生不可逆反应的过程，产生大量热量，使电池温度和内部压力升高，常常伴随着气体的燃烧。4.Severalscenariosan

5、dfactorscantriggerthermalrunaway.Overheatingofthecellcanleaddirectlytothermalrunawaybytriggeringaseriesofexothermicchemicalreactions.Overchargingcanleadtolithiummetalplatingontheanodeanddestabilizationofthecathodecrystalstructureduetoexcessivedelithiation.Mechan

6、icaldamage,crush,orpenetrationofacellcancauseashortcircuit,leadingtorapidheatingandthermalrunaway.Foreigndebristhatentersthecellduringmanufacturingcanalsocauseaninternalshortcircuit,leadingtolocalizedheatingandsubsequentthermalrunaway.几种情况和因素可能引发热失控。1.电池过热通过触发一系

7、列放热化学反应可能会直接导致热失控。2.过度充电会导致阳极上的锂金属镀层和由于过度脱锂而导致的阴极晶体结构的不稳定。3.电池的机械损坏，挤压或渗透可能导致短路，导致快速加热和热失控。4.在制造过程中进入电池的异物也会引起内部短路，导致局部发热和随后的热失控。5.Duetoallofthesepotentialhazards,numeroussafetymechanismsareoftenbuiltintoLi-ioncells.Asafetyventprovidespressurerelieftopreventelec

8、trolyteoxidationandgasgenerationfromreachingdangerouspressuresthatcouldburstthecellcan.Apositivetemperaturecoefficientdevice(PTC)actsasacurrentlimiterifacelloverheats