b'U.S. COAST GUARDU.S. COAST GUARD Marine Safety Alert: Lithium-Ion (Li-Ion) Battery System InstallationsI nJuly,theU.S.CoastGuardcompetent mariners, regardless of theBattery Management: Li-ion batter-issuedthebelowMarineSafetybattery bank size or end consumer.ies will often have a battery manage-Alert regarding Lithium-ion bat- mentsystemtopreventdegradation tery systems installations.UNIQUE SAFETY fromovercharging,undercharging, CONSIDERATIONSor over-cycling. Propulsion, electrical AnintegratedLi-ionbatterybankEnergy Density: Li-ion batteries areloads, topping loads, and recharging recentlycaughtfireonboardanin- usedonvesselsbecausetheirhighcyclesaremanagedbycomplexin-spected passenger vessel when looselyenergy densities allow for longer voy- tegrationsystems,whicharekeyin crimped lugs overheated. While no oneages and full electrification. Howev- mitigating the increased risks of Li-ion wasinjuredandthevesselsustaineder, high energy density increases riskbattery systems.minimaldamage,thiscasualtyhigh- because if a fire occurs, it will burn lights safety hazards unique to Li-ionhotter and longer.DESIGN REQUIREMENTSbatteries. All integrated (installationsTheCoastGuardprovideddesign used for propulsion and electrical pow- ThermalRunaway:Uponinternalguidance for integrated Li-ion battery er) Li-ion battery systems on inspectedfailureorshortcircuit,Li-ionbat- systems in CG-ENG Policy Letter 02-vesselsmustundergoengineeringteriesmayreleasehigh-temperature19 (PL 02-19), Design Guidance for plan review, be fitted with supportingflammablegasesthatcancatchfireLi-Ion Battery Installations Onboard safety systems, be tested and inspectedor explode. The heat output of a fireCommercialVessels,whichincorpo-atinstallationandperiodicallyafter- canincreasetherateofoff-gassing,ratesAmericanSocietyforTesting ward, and be properly maintained byand those off-gasses in turn increaseandMaterials(ASTM)F3353-19, the size of the fire in an uncontrolledStandard Guide for Shipboard Use of chain reaction.Li-ionBatteries.Theseintegrated systemsarehardwiredtopowerthe FireSuppressionResistance:Ashipselectricalloads;plug-inelec-thermalrunawayfireisverydiffi- tronicsandLi-ionbatteriesascargo cult to suppress once it has begun toare not addressed by this Safety Alert. propagatetootherbatterymodules.(See Safety Alert 01-22 for more infor-Instead,firemanagementstrategiesmation on Li-ion batteries as cargo.) focus on early detection, fire contain- As Li-ion battery technology evolves, ment, and heat absorption with a wa- additional guidance may be released.ter-based suppression system. PL 02-19 and ASTM F3353-19 address ToxicOff-Gasses:Inthermalrun- thefollowingmajorsafetyconsider-away,Li-ionbatteriesreleasevariedations for Li-ion battery hazards: ship toxicgases,manyinexcessoftheirspecificrisk/safetyassessments,bat-ImmediatelyDangeroustoLifeortery management systems, qualitative Healththresholds,placingpassen- failure analyses for vital ship systems, gersandcrewinpotentialdanger.designverificationtestprocedures Further, the composition of off-gasses(DVTPs),periodicsafetytestproce-variesdramaticallyacrossdifferentdures(PSTPs),hazardousareaplans Li-ion battery chemistries and manu- (fortoxicoff-gasses),structuralfire facturer makes and models.protection,fire/smoke/gasdetection FOGHORN 56'