Traction battery, strange balance after 4/5 weeks sitting still?

Hello all, I'm warning you that this post is somewhat speculative.

My Gen 2 has been in my garage for 4/5 weeks, turned off.
Few days ago I went to see the SOC of the traction battery (original one, car has twelve years, 2008, around 385000 km, ~240000 miles) but the 12v battery was dead (forgot to disable the smart key entry and to take away the Carista OBD 1 month ago.. ).
So, being in lockdown and needing to wait at least a week to receive a new battery or cables to jump-start the car, I took away the 12v battery, charged it up with my hair trimmer transformer and some wires transplanted from some unused cables, and put it back in today. It worked. Great. I started the car and saw a SOC of about 48%, not bad considering the age and all those weeks off.

While I was force-charging the traction battery, I noticed that something was different.

First of all, the internal resistance is 19 milliohm for all blocks, while I remember well that it wasn't the case before. I remember seeing a difference of 1-2 milliohm between the bottom and the top value.

Also, as you can see from the pictures, the outer blocks are the weakest in terms of voltage, while the others seem pretty even. Before, I had one internal block that was consistently the weakest of all. I don't remember whether it was block #4, #5, #6, or #7, but it was definitely there. Admittedly, I do not remember how the two outer blocks were doing.

I didn't drive the car today so, when I will drive it, maybe, the situation will revert as flows with more current will go back and forth from the battery. Yet, my question is this. Is it possible that by slowly discharging in time without use, the traction battery somehow balanced itself?

IMG_7790 by reallyreal posted Apr 16, 2020 at 7:45 PM

IMG_7792 by reallyreal posted Apr 16, 2020 at 7:45 PM

 

Aaah, I see, there's the catch then. Thanks!

Also, did you mean the blocks voltage distribution or the actual SOC?
I remember seeing a SOC value around 60% as soon as I started the car, and then seeing it drop to 48% almost immediately. Do you think I can trust the SOC value around 64% that I have now after force-charging the HV battery?

 

@TMR-JWAP Thank you very much for the clarification! As soon as I'll drive the car I'll also keep an eye on the voltage to see if its behavior will also go back to having a middle block as the weakest one.

@Aaron Vitolins Exactly. That's the reason why I didn't want to wait an additional 7/10 days for a new 12v battery. I don't know if it applies to all kind of batteries but as a general rule of thumb I know it's better not to let any battery discharge too much to avoid 'deep discharge' issues.