[RC-Monster Mike]

Captain was asking about a SCHULZE controller, but everyone answers with a bk controller answer. :)
The controller can likely handle the 20 cells, Captian. It isn't the voltage that kills the Schulzes, it is current and "loose connectors". have a look at the capacitors on the controller. BK uses 50 volt caps, while Schulze was using 25 volt caps. Bear in mind, a peaked cell will have higher voltage than the 1.2volt we use as a general guideline. I have overcelled some Schulze controllers with no ill effects, and have under celled other schulze controllers with ill effects. If you over cell the controller and it blows up, then your out of luck. If it works, then your in luck. Basically, it is a matter of whether or not you want to assume the risk. :)