The LP (liquid petroleum=propane) detector will alert if your batteries are low. When I go to check on the trailer, there are several rv's in the storage lot that have LP alarms alerting because their batteries are low.
I had issues with my batteries going dead until I had a battery cutoff switch installed on my trailer. I replaced two batteries that were beyond help only to have them stolen about a month later. Before I replaced them, I bought this:
http://www.torklift.com/index.php/products/security/powerarmor. I didn't get the one with the solar panel because I figured it would just get stolen. After the box was installed, I bought new batteries. Since I'm just a weekend camper, I couldn't justify paying the high price for the AGM batteries. I just bought 2, group 24 deep cycle rv batteries. Still cost me $100 for both of them. Our local tire store (Les Schwab) honored the price I had paid for the set that was stolen since the price had gone up by about $25/ea since I bought the other ones. I also had a police report so they knew I wasn't just trying to get a "deal."
If you plan on doing a lot of dry camping, it might be worth buying the 6 volt AGM's. Just get something to secure them to your trailer. If you decide to stay where there are always hookups (you know, glamping), then the group 24's will probably be fine.
I went camping last week for the first time since about October. With the locking battery box, the batteries were still there. With the battery cutoff switch, they had a full charge. I just turned the cutoff switch to "on" and proceeded to use the power jack without having to have the truck connected. It was great! I was really impressed.
So, I recommend securing your batteries somehow and I recommend having a battery cutoff switch installed.
Here is a link on how to wire the batteries together:
https://www.etrailer.com/question-21011.html This is only for 12 volt batteries. 6 volt batteries are connected differently.
Anyway, once you get on the road and hooked up to the Jeep, your batteries should stay charged. If they start smoking, replace them with new ones (don't ask me how I know THAT
)
Laura