Hi everyone as we are not on the road very often yet and our van spends most of its time in a shed where there in very little light for the solar panels to charg the batteries and there is no power in this shed I have a small solar panel that originally came from an electric fence energiser outside the shed getting some sun each day but it's just not quite keeping up so I have removed the lead from the battery to the van system so I am thinking of putting a kill switch in this line instead of undoing the terminal every time does anyone else have a switch in there van if so how big ( heavy ) of a switch should I use  there is two 225ah x 6v batteries fitted  and should it be on the negative or positive side 

You could use a manual resettable circuit breaker similar to this. Just press the button to open the circuit and push lever back to close it. 60A or 80A depending on what load you normally have on the battery.

Thanks troops that was what I think I was looking for so got one and fitting it today