Are we talking about 12 volt outlets or 120 volt outlets.
For 12 volt outlets you need a good battery. THey shoudl work no matter the source unless.. Well there is one very old converter where they might not.
For 120 volt. Well they don't work off battery unless you have an INVERTER.
IF you have SOME outlets that work on inverter and others that do not (I DO have that and it's 4 outlets I think that do not work in inverter in my rig)
Well a re-wire may be needed.. but be careful doing that.. Turns out two of the outlets that do not work also are connected to a 3rd that sucks major battery power if used that way.. Of course I can "Fix" that with a couple of button presses. but still.