No, I wouldn't disconnect the battery when camping. However while in storage, Yes. If you are going to leave it for days, I would disconnect the battery and charge it with a Intelligent trickle charger. ("Battery Minder" or "Battery Tender Jr".) These units will keep the battery at it's optimum with no risk of overcharging.
BTW, I sold my business last year and still have at least one of the Battery Tender Jr's new still in plastic packaging. They retailed for about $25. You can have this one for $20 plus shipping if you want it.
In any case it looks like you fixed your problem.
Jim and Katy
w/ Shelby and Sealy (Bernese Mountain Dog and a Nice Mut)
HAM CALLSIGN - AI4SR
EE, IBMer, Race Car Builder, now Retired.