[modmonster]

well, can you use a DC motor controller to charge car battery from a bigger higher voltage battery?

say you wanted to maintain 14.5v and didn't want the cars voltage to drop with your batteries depth of charge like with the single deep cycle battery. or you had several higher voltage batteries available and didn't want to cut them up. instead you could use the 24v or 48v and then use a DC motor controller to PWM it down to 12v.

would the 48v square wave mess with the cars electronics? or would the 12v car battery adsorb them if the controller was set low enough.