You are using the wrong scale. It does not mean the second half has most cells at the same voltage. They just go off screen so are being clipped.palmermd said:At 100% the difference is in the teens, at 80% which is where I normally charge to it is in the 20's, and at low SOC it is nearing 100mV (saw over 100mV last night when we got home). To me it seems like that one pair is what is limiting the entire pack. It sort of happened suddenly last spring. I had a drive I took every month that always had me home with a dozen or more miles remaining, and then one day I could not even make the trip and I was short by dozens of miles. I ended up driving 35mph in order to make it. Full charges from VLB is about 16kWh from the wall. Pack still says I'm at 90% capacity, and I have all 12 bars, but range is severely limited. I've had to take the Prius on this monthly trip since. I've tried it twice in the past year, and each time I've had to drive MUCH slower than I did before AND i'm charging on 120v while I'm there which I did not do before.
Interesting that the #28 is at the voltage where VLB occurs and I got VLB even though the other cells are well above. The other interesting thing is that the first half of the pack is scattered and slightly less than the second half of the pack which has more consistent voltages and they average higher. Sorry about the bad picture that I should have taken at the 100mV scale, but here is what I have from the other evening 107 during the day and it was still in the 90's at 11:30 when I got home hence the high pack temperatures.
If you see 82mv difference you should not be using a scale of 50 mv. The scale should be greater than the difference if you want to see the true max and mins.