FEDowner is correct, a cig lighter is just a heating element. 8v will work (a bit slower than 12v) and 16v will (quickly) as well. Once the element heats up, it releases itself and disconnects, so no harm no foul. And a cig lighter is only an occasional load, so it's not going to affect the "balance" of the multiple batteries in any significant way.
Another possible option: On a 48V golf cart, are the lights 12V? How about a radio? If so, you could also pic up 12VDC at the feed for one of those.