hi, I'd just like some advice on how best to charge a 70 amp hour deep cycle battery from a cigarette lighter socket. I use the battery to run my 35 litre waeco fridge when I'm camping for a couple of days, but would then like to charge the battery while travelling. I'm guessing a flat 70AHr battery will draw too much current from the car's circuit. Is there a current regulating device available for this purpose? My car has no room for a full RV style dual battery system. Thanks in advance, Ian. S.