Years back I took my new 2003 VW Golf TDI into a San Diego VW-Audi dealer to have a minor issue looked at. An hour later I felt in my gut something had gone wrong and sure enough got a call to say they had an "accident", bent rear wheel and torsion bar, body smashed in on one corner. Of course they wouldn't fix it themselves and the owner even verbally threatened me. A month later my car came back with a half-baked repair from a nearby body shop. It never drove the same, the back would hop to one side on bumps.... This is the very reason why I do all my maintenance on all of out cars.
What you are seeing is very normal. Good news, is that your battery looks good and does not show any bad cell groups. Re the variances, here is what the current SoulEVspy developer, Henrik Scheel, told me on email:So: I am done charging to 80%. . At this point, no more charge flowing tino the battery. Most of the cells show 3.94V, except from time to time , a seemingly random set of cells light up as 3.96V. It is a shifting pattern of 1 to 10 cells that light up for a few seconds, then a different set of cells light up showing 3.96V. So some cells seem to be oscillating between 3.94 and 3.96. I do not get why a random set of cells cells go up and down in voltage. The cells that do this are no necessarily the same ones. Finally the cells settle down. Just one cell is 3.96V, the others are all 3.94V
What's with that?
Well, rather than a "margin of error" he stated that the "precision of the voltage measurement" is 0.02 V. We don't know the overall accuracy of the analog voltage measurement. Adding more than 2 decimal places in the TP display doesn't help, which strongly implies that's a limitation of what's available over the CAN bus.... and he clearly says that is within the margin of error. It might help if there were 3 decimal places. Maybe Torque Pro has that?
I wondered this myself but realised that if you only have data in steps of 0.02 you can't assume anything that would allow rounding. However, you could just add 0.01 to all values to evenly distribute the error.I am guessing he rounds the actual value, possibly up or down, so if a cell happens to be just a tiny bit shy of the rounding limit, a minuscule voltage change may show up as a 0.02V oscillation. So the rounding may either amplify or minimize the displayed value vs. the actual voltage. Do we know if it is the actual measurement that has this resolution limit, or it is SoulEvSpy-s interpretation?...
1) Cell overcharge damage 2) Battery cell Separator manufacturing defect.
Both of these would be diagnosed by software, right?
Not really, was an outward facing service guy so not the EV mechanic. We did discuss how bad it would be to change the battery, sounded like a lot of logistics they have done before. Took it on a 200km commute this morning, went fine. Will charge it up again the next two nights and hit the 75 / 80 thresholds to make sue it does pause as expected.Congrats Mr P!
Were you able to get any more/new info out of the dealer or the techs?
Mostly Interested if the DIY cell monitoring and charge limit workaround some of us are practicing makes
Yeah check it out here. Hyundai Kona EV powertrain clicking soundMr P.
Sorry I must have missed an earlier post of yours in this thread or another. Your EV tranny is making a strange sound? I thought the EV had no tranny.
What is the 80 deg rotation? Thanks for explaining...