I've had a Nitecore I4 now for about a year and just got the 2014 model recently released also. I have had no problems charging Sony IMR VTC4/VTC5 or the Efest purple 20, 30, 35 amp batteries either, nor any battery it is stated to charge. I often charge 4 "High Drain" batteries at a time also including off my car cigarette lighter plug when camping.