Reg:
Did the calcs using the LeafSpy screen shot date with the following results (used LeafSpy numbers rather than a measured total pack voltage) :
Judgement value = 3.5595
Min cell voltage = 3.542
No DTC set => the calcs indicate bad cells/module needs replacement?
Are there other factors that are considered such as battery SOC, average battery voltage levels - or others? Seems I remember that the test can only be run a higher SOC conditions of the battery.
Wondering if I missed something or misinterpreted the CVLI process/calc ?
RegGuheert said:
1. PERFORM CELL VOLTAGE LOSS INSPECTION
With CONSULT
a. Select "DATA MONITOR" OF "HV BAT."
b. Check "MINIMUM CELL VOLTAGE."
Is "MINIMUM CELL VOLTAGE" 3,712 mV or less?
YES >> GO TO 3.
NO >> GO TO 2.
You are using LeafSpy instead of CONSULT and your MINIMUM CELL VOLTAGE is *exactly* 3,712 mV, so I will not type step 2 showing how to lower the voltage using the heater.
2011 Nissan LEAF Service Manual Revision: 2011 April - Page EVB67 said:
3. CALCULATE CELL VOLTAGE LOSS JUDGEMENT VALUE
With CONSULT
1. Check "DATA MONITOR" and record "TOTAL BATTERY VOLTAGE" and "MAXIMUM CELL VOLTAGE"
2. Calculate cell voltage loss judgment value.
Cell voltage loss judgment value = (2.5 x A - 0.144 x B) / 96
A = "TOTAL BATTERY VOLTAGE" (V)
B = "MAXIMUM CELL VOLTAGE" (mV)
NOTE:
The above equation of cell voltage loss judgment value is the simplified version of the following equation.
1. Calculate the average value of cell voltage by dividing "TOTAL BATTERY VOLTAGE" by 96 (the number of cells)
Average cell voltage = "TOTAL BATTERY VOLTAGE" / 96
Of course, LeafSpy gave you this value directly:
3.851V
2011 Nissan LEAF Service Manual Revision: 2011 April - Page EVB67 said:
2. Calculate cell voltage loss judgment value.
Cell voltage loss judgment value = Average cell voltage - ("MAXIMUM CELL VOLTAGE - Average cell voltage) x 1.5
From LeafSpy, we get:
Cell voltage loss judgment value = 3.851V - (3.861V - 3.851V) x 1.5 =
3.836V
2011 Nissan LEAF Service Manual Revision: 2011 April - Page EVB67 said:
>> GO TO 4.
4. JUDGE CELL OF VOLTAGE LOSS
With CONSULT
a. Record "CELL VOLTAGE 1-96" with "DATA MONITOR".
b. Check to see if there is "CELL VOLTAGE" which is less than or equal to the judgment value.
OK: Cell voltage loss judgment value < CELL VOLTAGE 1 - 96
NG: Cell voltage loss judgment value > CELL VOLTAGE 1 - 96
Is there a cell voltage which is the judgment value or less?
YES >> Replace module including cell voltage the judgment value or less. Refer to [EVB-153, "Exploded View"
NO >> INSPECTION END
3.836V is significantly higher than the voltage of your cell-pair 4, which is
3.712V. This is the clearest case of a failure of this test that I have seen. [/quote]