Replacing the single cells in the battery pack?

[kojairvs]

We can agree that the BMS stops charging the cells when they (or at least one of them) reach 4.1V
My car this morning showed 95% and the graph showed 4.08V on all cells (as shown on the photo/graph). That is very positive because then they are all almost the same capacity, let me remind you that on the old battery all but one had 3.8V at 100% battery because the first cell reached 4.1V very quickly and all the others remained half empty.
When the BMS shows close to 0% battery then how much did the cells go down? 3.3V?

 

[kojairvs]

These are my self-made cables for the battery connection that sits next to the car, to check how good it is and will the car accept it before I start installing it. . The real DIY

 

[kojairvs]

Thanks for sharing your experience. I've learnt a lot from this whole thread.

I got your point about keeping the cells for yourself.

About cell compatibility:
As I wrote here: https://www.mykiasoulev.com/threads/replacing-the-single-cells-in-the-battery-pack.1906/post-15183

E-service in Hungary offers to replace old packs with used, newer packs from other cars (not necessarily Kia/HyundaI, but preferebly, whichsoever is available for them to purchase from the used/damaged cars market).
Since they don't touch the BMS's deep settings, the old BMS will charge the newer cells to the same Voltage level as the original SKI E375 limit, eventhough the newer cells have higher Voltage limits & could be charged higher, but the old BMS will stop the charging process sooner. According to e-service, this will help to keep your newer cell alive for longer period, as the old BMS will never reach the possible 100% charging level of the newer cells.

Also the displayed range will not be exact, as the real possible range will be higher, because the newer cells can keep more charge compared to our old geniune cells even though their full charge level will not be reached ever, but our old BMS is programmed to show only 210km as max. (or something like this, they said).

They are not mixing different cell types, but replacing the full cell-packs, which can fit into the old battery housing, keeping the old BMS.

I think, mixing the E375 & E400 cells would not be a good solution on the long run, especially I would not recommend to pair the different types in once circiut, but surely better than nothing.

So, in case they can do this with cells from batteries disassembled from other car types, maybe it's not a big deal, so maybe I can also do that as you did, but using cell packs from a crashed Ioniq (2nd gen.).

What do you think?

I have no clue about the batteries of the other cars, I’ve learned lots from this forum but no experience to back it up. I would not dare to give you un advice what to do, just trying to learn myself, use that knowledge on my car and share that experience here which might help others not to make my mistakes .
Sorry