Could have also just been a dud pack. Or could well have been a cold joint or some other issue.

If running packs in series is so bad, then we should be seeing constant failures in the RC heli world. Helicopters are far more power hungry and running series is pretty much the norm for large helicopters. Even our single stick packs are technically twin packs in series that you can charge independently or in parallel.


Dave H
You're right, I should not have used the word "impossible." I should have clarified... it's impossible to get a true reading, since pairs (or triplets or whatever) of cells are seen as one. Sure, it's possible to get a good balance when parallel charging, but you have no way of knowing if there is a problem because you cant see individual cell voltage, so as a safety precaution, I will run them individually once a week and monitor the pack. I've had instances where one cell was giving me trouble but after balancing it independently, it would go back to normal for a while.

I've also been parallel charging for many years, safely, with no problems. My biggest words of caution are, let the packs equalize for a few minutes and definitely get a fused paraboard. Usually not a problem if you don't let them equalize, but it only takes one unseen problem to cause a fire. Stay safe out there!