Our camper does not have a battery disconnect. And I have never had occasion to want one. When do you use yours? (And don't say "When you want to disconnect the battery.")
Start with checking what voltage your charger supplies. Lot of converters have the voltage >14V and you don't want that for long time. Same applies to solar chargers. I always disconnect my batteries when in storage after giving them good charge at the end of the season.