I use my race packs only once per day and my practice packs twice if necessary.
After running the pack in the car I'd discharge it to 5.4V @10A, then Ill tray it with a Trinity 2.5 until all the lights go out.Then I store them till the next charge.
Before charging I'd put them into another Robitronics tray with cut-off (takes at least 2-3hrs)when the lights dim, it's time to charge.
I try to time the charge to end at when I'm going to need them, but usually i charge at home and repeak at the track.