What is normal voltage deviation between series connection?

I've checked my series connection one by one and I've noticed that the deviation went from two series having -0.01V to multiple series going +/- 0.02. Average come ~4.2V fully charged, but 1S and 14S have a difference of 0.05V.
Cells voltage as of right now:
1S 4.17V-------8S 4.20V
2S 4.20V-------9S 4.22V
3S 4.20V-------10S 4.19V
4S 4.20V-------11S 4.20V
5S 4.19V-------12S 4.22V
6S 4.20V-------13S 4.20V
7S 4.20V-------14S 4.22V

Not much to worry about like that for static voltage tests.

What do you get under load during discharge?

And during charge at various points?

amberwolf said:

Not much to worry about like that for static voltage tests.

What do you get under load during discharge?

And during charge at various points?

Click to expand...

Both discharging at 20A and charging at 5A had a deviation of 0.01V. I usually charge my battery to 4.1V, but from time to time I fully charge it to let it balance itself. Interesting is that my battery stays balanced(+/- 0.01V) at and below 4.1V per series, but if I fully charge and let it balance itself the difference grows to (+/- 0.05V)

Those cell voltages read rather very good.

I’m at the moment similar issue although two cells are now up 3.8 and one cell is lagging at 3.5 volts.

Just ordered a smart BMS, to assist this latest charger of charges at 8 amps to 40.50 volts. Will trim it down further to 40 volts when the new BMS is installed.

Stuck with the 2 amp 42 volt charger for the time being the unit is charging a 13p battery and I doubt could sustain that Ah any length of time.

What will happens with old batteries is that you get a cell (or two) that start to flake out on you. Most notably you will charge to 4.2 volts per cell and you get a cell that will only go to 4.15 or another thing that happens is that you will discharge down to 3.8 volts per cell and you will have that one stinker that goes to 3.65 volts. Eventually that one cell will get worse and worse on you (4.1 volts 3.6 volts ect...) until you get a 0 volt cell.