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Page1of6|April2018|www.ehs.washington.edu|LithiumBatterySafetyLITHIUMBATTERYSAFETYSUMMARYLithiumbatterieshavebecometheindustrystandardforrechargeablestoragedevices.TheyarecommontoUniversityoperationsandusedinmanyresearchapplications.Lithium-ionbatteryfiresandaccidentsareontheriseandpresentrisksthatcanbemitigatedifthetechnologyiswellunderstood.Thispaperprovidesinformationtohelppreventfire,injuryandlossofintellectualandotherproperty.BACKGROUNDLithiumbatterieshavehigherenergydensitiesthanlegacybatteries(upto100timeshigher).Theyaregroupedintotwogeneralcategories:primaryandsecondarybatteries.Primary(non-rechargeable)lithiumbatteriesarecomprisedofsingle-usecellscontainingmetalliclithiumanodes.Non-rechargeablebatteriesarereferredtothroughouttheindustryas“Lithium”batteries.Secondary(rechargeable)lithiumbatteriesarecomprisedofrechargeablecellscontaininganintercalatedlithiumcompoundfortheanodeandcathode.Rechargeablelithiumbatteriesarecommonlyreferredtoas“Lithium-ion”batteries.Singlelithium-ionbatteries(alsoreferredtoascells)haveanoperatingvoltage(V)thatrangesfrom3.6–4.2V.Lithiumionsmovefromtheanodetothecathodeduringdischarge.Theionsreversedirectionduringcharging.Thelithiatedmetaloxideorphosphatecoatingonthecathodedefinesthe“chemistry”ofthebattery.Lithium-ionbatterieshaveelectrolytesthataretypicallyamixtureoforganiccarbonatessuchasethylenecarbonateordiethylcarbonate.Theflammabilitycharacteristics(flashpoint)ofcommoncarbonatesusedinlithium-ionbatteriesvaryfrom18to145degreesC.Therearefourbasiccelldesigns;button/coincells,polymer/pouchcells,cylindricalcells,andprismaticcells.(seeFigure1).Figure1.TypicalCellDesignsPage2of6|April2018|www.ehs.washington.edu|LithiumBatterySafetyThemostcommondesignsprevalentinacademicandresearchuseincludepolymer/pouchcellstypicallyusediniPods,tabletsandcellphones.Cylindricalcellsincorporatethesimilardesignparametersthathavebeenthestandardforalkalinecellsforyears(A,AA,AAA,C,andDcells).Prismaticcellsarethin,squarecellswithhardsteelcases.Prismaticcellsaretypicallyusedincellphonesandthin,laptopcomputers.Otherthancellphonesandtablets,mostportableelectronic/electricaldevicesoperateabovethenormaloperatingvoltageofsinglelithium-ionbatteries(3.6–4.2V).Forsuchdevices,numerouscellsconnectedinpacksprovidethedesiredvoltageandcapacity.Connectingcellsinparallelincreasespackamperageanddischargecapacitywhileconnectingcellsinseriesincreasespackvoltage.Asanexample,a24Vlithium-ionbatterypacktypicallyhassixcellsconnectedinseries.Manybatterypackshavebuilt-incircuitryusedtomonitorandcontrolthecharginganddischargingcharacteristicsofthepack.Asanexample,circuitrywillautomaticallymanagethechargingwhenthepackcellsreach4.2Vand/orifthetemperatureexceedsapresetvalue.Thecircuitswillshutdownthepackifthecellsdischargebelowapresetvalue(e.g.,3.3Vpercell).Thecylindricalcell(identifiedby“18650”)issimilarinsizeandshapetoanAAbattery.Itisthe“workhorse”ofthelithium-ionbatteryindustryandisusedinamajorityofcommerciallyavailablebatterypacks.ExamplesareshowninFigure2.Figure2.Battery/BatteryPackExamplesLITHIUM-IONBATTERYHAZARDSLithium-ionbatteryfirehazardsareassociatedwiththehighenergydensitiescoupledwiththeflammableorganicelectrolyte.Thiscreatesnewchallengesforuse,storage,andhandling.Studieshaveshownthatphysicaldamage,electricalabusesuchasshortcircuitsandovercharging,andexposurestoele...