RE: LIFE battery charging in the plane question
Add balance connectors. That's great, but I will say that using LIFE(both A123 and plain LIFE) packs for receiver packs I do not balance them. As I understand if you are drawing small current and charging a reasonable level(under 1C), no balancing should be required. 2 seasons and counting...and I'm not the only one at our location.
LIFE are not LSD they are NSD (low self discharge, no self discharge) effectively. Forget to charge the pack flown 6 months ago, which was drawn down 20%, you'll still have most of the 80% left and are safe. NIMH, even Eneloop are LSD. Low internal resistance so they perform well when a higher draw is required.
Oh, did I mention price. I sell LIFE 1100 mah packs here LPU for $10 or 2 for $15, sometimes.