Here are some curves to make things clear.
Have a zoom in look
there are two groups of curves, cell 1/4/6 (brown/pink/dark blue) presents far higher voltage under 7A charge current, unless during charge pause period they get close. The "spikes" are 3 second charge pause every minute, you can see the "bad" cells have huge spikes compared to the good cells, reflecting much higher internal resistance.
Now the discharge characterestics, same result, the bad cells have large voltage drop under only 3.2A discharge current. the good cells(red/yellowgreen/light blue) have smoooooth curve(low voltage change when current varies) and are very close from each other, while the bad group are full of glithes and far apart front the good.
