SURFACEISSUEDVEHICLEJ2288JAN97RECOMMENDEDIssued1997-01400CommonwealthDrive,Warrendale,PA15096-0001PRACTICESubmittedforrecognitionasanAmericanNationalStandardLIFECYCLETESTINGOFELECTRICVEHICLEBATTERYMODULES1.Scope—ThisSAERecommendedPracticedefinesastandardizedtestmethodtodeterminetheexpectedservicelife,incycles,ofelectricvehiclebatterymodules.Itisbasedonasetofnominalorbaselineoperatingconditionsinordertocharacterizetheexpecteddegradationinelectricalperformanceasafunctionoflifeandtoidentifyrelevantfailuremechanismswherepossible.Acceleratedagingisnotincludedinthescopeofthisprocedure,althoughthetimecompressionresultingfromcontinuoustestingmayunintentionallyacceleratebatterydegradationunlesstestconditionsarecarefullycontrolled.Theprocessusedtodefineatestmatrixofacceleratedagingconditionsbasedonfailuremechanisms,andtoestablishstatisticalconfidencelevelsfortheresults,isconsideredbeyondthescopeofthisdocument.Becausetheintentistousestandardtestingconditionswheneverpossible,resultsfromtheevaluationofdifferenttechnologiesshouldbecomparable.End-of-lifeisdeterminedbasedonmodulecapacityandpowerratings.Thismayresultinameasuredcyclelifedifferentthanthatwhichwouldbedeterminedbasedonactualcapacity;however,thisapproachpermitsabatterymanufacturertomakenecessarytradeoffsbetweenpowerandenergyinestablishingratingsforabatterymodule.Thisapproachisconsideredappropriateforamaturedesignorproductionbattery.ItshouldbenotedthattheproceduredefinedinthisdocumentisfunctionallyidenticaltotheUSABCBaselineLifeCycleTestProcedure.1.1FieldofApplication—ElectricVehicles1.2ProductClassification—ElectrochemicalStorageDevices1.3Form—AnElectricVehiclepropulsionbatterywillconsistofabatteryconfigurationofseveral(typically12V)modulesinterconnectedinoneormoreseriesstrings.Thisdocumentprovidestestmethodstodeterminethelifeexpectancyofsuchmodules,includingbutnotlimitedtomodulesbuiltinaccordancewithSAEJ1797.Useofthisdocumentisintendedforsingleindependentlypackagedmodulesoperatingatamb