It charges A123 cells. You just set the max volts to 3.6 volts. I Think it is solved but I am not sure. I think it was overheating. I have put a large opening in the cowl in line with the firewall openings. I have since done a ground run and a test flight today. It did not shut down. Castle just told me that a momentary loss of signal will shut down the ESC and by returning the throttle to zero and then throttlling up power will be restored. I did not know this. I also know that every once ahwile I get a small throttle rev up when the main power is connected. I have a 72mhz system. Signal loss or overheating not really sure. I had one very knowledgable guy tell me he has never had a Castle overheat and shut down. Cheaper ones yes but not a properly sized Castle.