Most travel trailers have the battery or batteries on a tray on the frame at the front of the RV, and there is no place for a battery-disconnect switch. I solved this problem by purchasing a set of welding cable connectors at my local welding-supply store.
I cut the negative cable from the battery in half and installed the male connector on one end and the female connector on the other. I then plugged the two connectors together and gave them a twist, which locks the connectors in place and gives the battery a secure and waterproof connection.
When it’s time to disconnect the battery, I simply twist the two connectors the other way.
Gordon Hansen | Springfield, Oregon