Hi guys i am new to this lipo charging business, any here is my problem.When i try to balance my batteries with flightpower v balance half of all my batteries balance fine.the other lot sit on the balancer for up to five hours and still not balanced. Have i stuffed these batteries, because i am new to this and have never been told until recently that i should not run the batteries down to the low voltage cut off which i have done many times. My swallow 2 charger when charging through the v balance displays open battery circuit .