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Discussion Starter #1
How much is battery cell voltage when battery is fully charged? Please add total miles info.
 

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A gen1 volt should be 352V pack voltage when "full", IIRC.
With 96S3P that's 3.666666666666666666667V per cell.
 

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Discussion Starter #4 (Edited)
I get 3.9V (90.000km), battery is only 85% SOC-U full in reality, computer show 100% SOC-U.

I think full charge should be around 4.1 - 4.2 this could explain my issue, where computer thinks that he got 100% in reality he have only 85% SOC-U, because charging is stopped at 84,5 SOC-U (73,7 SOC-R) and computer flips it to 100% in a second.

http://gm-volt.com/forum/showthread...ttery-or-battery-management-system-missing-20
 

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Most LiIon chemistry is about 4.2V for 100% SoC. But Volt never charges to 100% to maximize lifetime charge cycles, and reduce degradation. A "full" Volt charge is only about 4.0V per cell, or about 285-290V for the whole 96S stack.

3.6V to 3.7V is "nomimal" cell voltage that which the capacity is often rated at. And the "nominal" pack voltage of 352V. It's definitely not "full" at 3.66V.

I don't know what the low voltage cut off is, but it's probably down around 3.2V per cell (around 24% SoC), depending on discharge rate, temperature, and who knows what else...

These are approx. gen 1 numbers, gen 2 has wider SOC/voltage limits.
 

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My measurements with MyVoltHold and MyGreenVolt are consistently 4.0v per cell full, and 3.5v empty, at standard operating parameters, (normal full charge to extended range switching)
 

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4.05v is what I read with GDS2 on a full charge. Somewhere around 3.5v empty. Dont remember the exact number.

70,000 miles, still get 40 miles a charge.

You're issue may be related to the faulty cell balancing software that was recalled the other day.
 

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3.6V to 3.7V is "nomimal" cell voltage that which the capacity is often rated at. And the "nominal" pack voltage of 352V. It's definitely not "full" at 3.66V.
Yeah, this makes sense now.
The OBD PID calculation value I have must be incorrect, as it definitely reads 352V when "full" (83.53% SOC) - I just double checked a screenshot I had on hand.
 
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