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Interesting that you see the car still trickling a tiny charge after 'finishing' the 6A charge.
It happens consistently if I charge from "empty" at 6A. However, if I "top up" it only happens inconsistently, especially if I am topping-up after already topping-up. As far as I can tell it doesn't happen at 7A.
 

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Datapoint...

This drive was done very similar to the other (no climate control, no stereo, no USB, no OVMS, topped-up but not preconditioned, dry roads, few stops and costing to those). The differences were:

1) I drove in "Sport" mode.

2) I drove faster (55-65 mph).

3) I drove "sporty": accelerated quickly and passed slow traffic a few times.

4) The ambient temperature was 15-20 degrees Fahrenheit less than the last datapoint.

I note that there was no effect on the "kWh used".
 

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Back to this now that I have the Volt again...



I modified the route a little bit in order to get the total trip closer to 50 miles. If I had not wanted to get so close to 50-miles I could have avoided a big hill and got over 50 miles on the battery. Maybe I will do that some other time.

Anyway, this drive was mostly just to verify that all is well with the battery and motor after the accident and repair. It seems to be in good shape.

The temperature was quite constant at 75 degrees Fahrenheit. Because of the route change I was able to avoid a heavily-trafficked 50 mph zone and was able to keep the speed down. I had the climate control off, headlights off, USB unplugged, OVMS unplugged, and infotainment system off.

The results are quite comparable to the first drive (more than a month ago) which got 46 miles on the battery. The 3-mile difference likely has to do with avoiding the 50 mph section of highway.

Anyway, the point here is really that the Volt is performing exactly as it was before, and so I can move onto other tests.
 

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Yesterday, after a 35.4 mile trip to a destination (mostly at 65 mph freeway speeds) I turned off the Volt with 1 mile left on the battery and with an indicated 9.5 kWh used. After about an hour at the destination I started the Volt to find it now in charge-sustaining mode.



I've seen this kind of thing before. It basically illustrates what was said in the linked FAQ above: that is that the "kWh Used" does not take into account any adjustments made by the BMS while the Volt is turned off. The most-likely explanation of what happened on that specific trip is that some "settling" of the charge in the cells happened - and that "settling" led to a reduction in the usable battery capacity for that trip. This follows a trip made two days earlier to the Seattle Electric Vehicle Association meeting where 9.7 kWh Used was shown (as usual). Does it mean that the Volt experienced 0.2 kWh battery degradation in 48 hours? Of course not.
 

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If you have less than 3~4km left, it will go straight to CS mode when you start up again. The spare battery then becomes the CS buffer.
 

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So... 9.9 kWh Used instead of the usual 9.7 kWh Used. This trip involved multiple stops. Also, it involved a few hours being disconnected from the charging station before initial departure. The last charge was a very short one. The trip previous to this was maybe only 5 miles.

What I am certain of, however, is that it did not get a battery replacement.
 

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And suddenly it wants to use 10.2 kWh instead of 9.8 kWh. (Maybe having software updates done prompted this.) Again, the charge before this trip was very short because the previous trip was only 2 miles.

So, the same vehicle varies between 9.5 kWh and 10.2 kWh. My recollection was that last summer I saw 10.2 kWh... and I was beginning to think that I was mistaken and that it was because I had partially charged during one trip (which I sometimes do if a charging station is convenient or if I return home only to shortly need to leave again).
 

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I won't bother with the photo, but we're back at 9.7 kWh used tonight. So, the software update probably wasn't a factor.

I really think that it has something to do with that short previous trip.
 
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