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Discussion Starter · #1 ·
Parked at home and charging from the OEM EVSE at 120VAC. Car is set to charge at 12A.

Twice now after the charging indicator on the dash reads full (solid light) the EVSE continues to draw current. Assumedly the current is going to battery conditioning?? Tonight when it happened it was 48F. Current draw runs from roughly 7-12 amps AC (amp meter in house), and can occur for several hours (or more?).

Here are some screen captures from Torque Pro:
27954

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27957
 

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2022 Bolt EUV Nov build
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I wonder the same thing. I set my departure charge for 6am, it started charging at 4:30, "finished" by 5-ish... maybe taking an hour to allow cell balancing?
 

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Discussion Starter · #3 · (Edited)
I am still thinking it's simply keeping the battery warm (if all is well), because since I posted the current stopped flowing for a while, then started.... stopped....
 

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My car does this too while charging using a JB Pro 40. Onstar App shows SOC "FULL" but charger app still shows current flow, albeit diminished.

My theory - "FULL" is anything above 99.0%, and there may be some equalization / conditioning going on. This condition is meaningless / insignificant, other than the minor annoyance that the infotainment miles / kwh since last full charge indicator doesn't reset.
 

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My car does this too while charging using a JB Pro 40. Onstar App shows SOC "FULL" but charger app still shows current flow, albeit diminished.

My theory - "FULL" is anything above 99.0%, and there may be some equalization / conditioning going on. This condition is meaningless / insignificant, other than the minor annoyance that the infotainment miles / kwh since last full charge indicator doesn't reset.
Yes, full is a fuzzy concept. There is always a taper at the end of an un-interrupted charge session [cell balancing or topping off, etc.]. Here's the taper on a L2 charge:
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There are 2 different SOC readings -- "user" [228334] the value you see in the app, and a few different "raw" PIDs, which are a few % different than "user". One of the "raw" PIDs [22432f] gives you a higher resolution than all the others [which are at best 0.6% resolved]. Another view of SOC is to read the battery cell voltages.
https://batteryuniversity.com/index.php/learn/article/how_to_prolong_lithium_based_batteries has some interesting tables for this. "100%" is 4.20 volts; this is probably the "raw" value, not user.

After a charge like above, I can suck more than 1 kWh out of the battery before the app says something other than 100%.
 

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12/16 build, 2017, white LT
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Assumedly the current is going to battery conditioning?? Tonight when it happened it was 48F. Current draw runs from roughly 7-12 amps AC (amp meter in house), and can occur for several hours (or more?).

Here are some screen captures from Torque Pro:
I am confused. Why are you assuming anything? You have Torque Pro. There are PIDs, in the file you are using, that show battery heater watts, AC compressor rpm, 12 volt accessory battery charging volts, and onboard charger volts, amps, and kW..
 

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Discussion Starter · #7 · (Edited)
I am confused. Why are you assuming anything? You have Torque Pro. There are PIDs, in the file you are using, that show battery heater watts, AC compressor rpm, 12 volt accessory battery charging volts, and onboard charger volts, amps, and kW..
Mr Jetson, the reason for your confusion may be due to an assumption you are making that I was aware of the battery heater watts PID. When I first set up Torque I added a bunch of PIDs, but did not notice that one. Thanks for the reminder that that function can be monitored. Funny enough, after making the post I was adding all 96 PIDs for the cell voltages and stumbled across the battery heater PID and added it. I will be fully charging the car at home in a couple of days and will check to see what device may be drawing the power.

None the less, there is a bit of a rabbit hole here. It actually seems the battery was being warmed in the overnight session posted because the range estimator had a much higher reading than typical this morning. Before recently changing tires from Michelin to the Continentals (made a separate thread for this) the car consistently reported 255-265 miles of range when fully charged at home with the OEM EVSE (the only time the GOM is uniform and repeatable). This was a constant time after time for the past 9 months of ownership. After switching to the Cons the range consistently reads 190-200 miles under the same conditions. Again, this is a repeated reading every full charge at home since swapping tires. This is much more of a drop than expected (per other reports on the tires in this forum). However, after the activity reported above last night, the GOM this morning reported 238 miles. This is much closer to the approx 10% range loss expected for the Cons.

The Cons were swapped in right around the time our temperatures started dropping here. So now I am less puzzled by the activity last night -which for the moment the evidence points to the battery being conditioned/warmed- and more puzzled as to why the car has not been behaving this way whenever the temp drops to where it did. All this time the Continentals seemed a major disappointment. But now I'm not so sure. Will be doing some further testing....
 

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12/16 build, 2017, white LT
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Unfortunately, the onset and amount of battery conditioning, with a 120 volt EVSE, is limited. On 240 volts, even the stock EVSE can deliver the full 2+ kW the battery heater pulls at the end of a charge cycle. Torque Pro is wonderful. I can't thank Telek enough.
 

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2017 Bolt EV
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...the car consistently reported 255-265 miles of range when fully charged at home with the OEM EVSE (the only time the GOM is uniform and repeatable). This was a constant time after time for the past 9 months of ownership. After switching to the Cons the range consistently reads 190-200 miles under the same conditions...
It's very tempting to ascribe more accuracy to the car's range estimate than it warrants, but doing so can lead you way down some deep rabbit holes...
 

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Discussion Starter · #10 · (Edited)
It's very tempting to ascribe more accuracy to the car's range estimate than it warrants, but doing so can lead you way down some deep rabbit holes...
Perhaps, but I did verify the initial drop after switching tire brands and actual miles were down by about the amount the GOM estimated.

EDIT: And I did have additional range before needing charging at 10% full yesterday, the day after the extra juice was drawn and the GOM jumped up.
 
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