Hi Chris,

A three cell pack is not a good idea. You will dissipate more power in the regulator and that does mean more heat. In our electrics the average current is pretty low so you may get away with it but I'd switch to a two cell pack. I've been running Lithiums for years and have never seen a failure. From what I can see they wear out slowly and the mode is high internal resistance which results in fewer flights per charge and longer time to charge. In Li-Ions this seems to happen in about two years if you use them or not. I don't know about Li-Polys yet.

Jim O