I don't think you need a float charge on lithiums, what does the manufacturer of your battery say about this? But you will need to keep up with any parasitic loads, like the CO/propane detector, tank monitors, etc. Things you cannot shut off unless you disconnect the battery, when stored.
I only exaggerate enough to compensate for being taken with a grain of salt.
I bought the camper second hand. The manual doesn't cover much. In winter I go out and fool around with it some and having it hooked up is handy, however it is easy to hook up. I am installing a battery shutoff switch and I will be unhooking the cord and the battery this coming winter.
If you guys disagree with this procedure let me know.