Well, with a lot of patience. From what I've learn it seems that after you bring a cell down to 2.7v you need to wait to see where it goes. That is after 24hrs you might find a higher voltage upon measuring. Cells chemical almost organic things. If that is the case you want to discharge the cell again to 2.75 v and wait.
You do the same with the rest of the pack. If you see anyone that has gone under (a BMS measuring bottom voltage) then you pump it up back to 2.75v. Once you see that 24hrs go by and the cells are stable then and only THEN you charge them to specs.
You will see that after several cycles they go down at the same rate which is what you want for them to have a long life.
There is a site evtv me that has a couple of programs dedicated to bottom balancing LiPoFe. Peace.
P.S. I found the link but I'm going to leave spaces instead of the dots since it does not let me post it.
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