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Discussion Starter · #1 ·
I'm getting 13.7 amps and 1.7 kW [measured with a Kill-a Watt on the AC charger plug] with the OEM L1 charger now on my 2017 LT. That's up from 12.0 and 1.4 kW with the old battery / old battery SW. Anyone else see this?
 

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I haven't plugged in my OEM EVSE since the new battery, I'm interested enough to try it tonight.
Are you comfortable with the accuracy of your Kill-a Watt? I have a different brand but will try it over the weekend.
 

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I think you are measuring the wrong side of the equation. Kill-a-Watt measures energy sent to the EVSE, including resistance losses. The OBC on the Bolt was not changed, it is still processing 1.44kW at 12A. The EVSE is limited to 12A, so the car will never get more than that.
 

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Discussion Starter · #4 ·
I think you are measuring the wrong side of the equation. Kill-a-Watt measures energy sent to the EVSE, including resistance losses. The OBC on the Bolt was not changed, it is still processing 1.44kW at 12A. The EVSE is limited to 12A, so the car will never get more than that.
That is correct, but the measurements made at that same wrong point have changed [increased current/power]. The EVSE is pulling more power from the wall, and I'd assume it's not going up as heat inside the EVSE. Or maybe GM messed up the SW and it's going up as heat inside the car... I suppose I could find a PID that would tell me what the car is using, but I have nothing to compare that with the old battery.
 

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Discussion Starter · #5 ·
I haven't plugged in my OEM EVSE since the new battery, I'm interested enough to try it tonight.
Are you comfortable with the accuracy of your Kill-a Watt? I have a different brand but will try it over the weekend.
Can't speak to the accuracy of the KAW [it ought to be decent, and not change much over time], but it's the same one I've been using for a few years to watch the EVSE. I do have a 2nd one and could switch to that next time.
 

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Interesting that it changed from battery to battery. GM might have limited charging on the old battery to help prevent fires ?

New Battery: 13.7A from the wall into 12A at the car would be 87.6% efficiency rating, which is in the range of AC->DC conversion efficiency in my line of work (85-95%).

Old Battery: 87.6% of 12A would be 10.5A.

Seems plausible that in addition to artificially reducing battery capacity to 80% they would also throttle input amperage 15% ?
 

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Interesting that it changed from battery to battery. GM might have limited charging on the old battery to help prevent fires ?

New Battery: 13.7A from the wall into 12A at the car would be 87.6% efficiency rating, which is in the range of AC->DC conversion efficiency in my line of work (85-95%).

Old Battery: 87.6% of 12A would be 10.5A.

Seems plausible that in addition to artificially reducing battery capacity to 80% they would also throttle input voltage 15% ?
Interesting, I will try mine out and post what my monitor shows.
 

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That is correct, but the measurements made at that same wrong point have changed [increased current/power]. The EVSE is pulling more power from the wall, and I'd assume it's not going up as heat inside the EVSE. Or maybe GM messed up the SW and it's going up as heat inside the car... I suppose I could find a PID that would tell me what the car is using, but I have nothing to compare that with the old battery.
If you don't already have one, these BAFX OBD2 bluetooth readers are great. I've got 2 of them and use one with Torque Pro 100% of the time when driving my truck.
 
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