loadingCycle life test
General cycle life?Charge to 20% DOD every cycle
?Voltage:4.2V for charge and 3V for discharge?Reference performance test every 25 cycles
ChinaWorking condition cycle life?Start at 30% DOD
?Repeat the test profile 100 times as a cycle?40%DOD 1 cycle , 50%DOD 2 cycles ,60%DOD 2 cycles ,50%DOD 2 cycles ,40%DOD 1 cycle ,30%DOD 1cycle
End-of-test condition: degradation of the battery capacity is more than 20%
Self discharge
Self Discharge=USABCCapacity measurementTest conditionTest temperatureNominal intervaldischarge use a constant scaled 10-KW rate to voltage limit(Wh)remove the CD available energy30 oC7 days or interval yield capacity loss of more than 5?efore test?(Cpart1+Cpart2)Stand Time in DaysChinadischarge use 1C current to voltage limit(Ah)full charged state20 oCand 55 oC28 days at 20 oCand 7 days at 55 oCCapacity recovery: there must be no visible capacity loss before and after self discharge test
Thermal Performance
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Laboratory cell level:
?Characterize the performance as a function of temperature?Bound the likely constraints on thermal managementSystem level:
?Thermal management system design and behavior
USABCInitial FullyChargeTemperatureTarget TemperatureThermal Equalization TimeTest Content30oCNot specify(-30 to +52oC)4-8hcapacity test Low HPPCtestfraction of the CS Available power targetChina20oC-22oC and +55oC16h at -22oC and 5h at 55oCcapacity test Hybrid pulse testDCresistancesenergy efficiency at various temperatureObjective Calenderlife test
?Careful planning and analysis of calendar life tests are critical to estimation of battery life with high confidence.
?Calenderlife esimmatesare necessarily based on accelerated test methods(High temperature)?Achieve high rates of deterioration to minimize test time and cost
?Avoid introducing irrelevant failure modes at too high temperature
Interesting cooperation area
?The life accelerating test method.
?The safety performance evaluation grade definition
?Mechanism of safety