I was on vacation for a week and couldn't get to RV.net so I'm working through the withdrawals by posting even to older questions.
If you leave the battery connected in storage the various devices will drain the battery. Based on your post there are really two solutions.
- Disconnect the negative cable of the battery for storage.
- Install a battery disconnect switch so you can disconnect the battery while in storage.
Yes you want the battery to be charged before hand as storing a battery in a partially discharged state will damage it.