Yes, you can recharge the batteries at home and re-install them later.
Unless the trailer is very old, it will have a decent converter in the power centre that will charge the batteries as well as maintain them. What is the model of converter you have?
Older converters did need the battery connected to act as a filter for the DC power to some of the Rig's systems, but newer (since 1998-2003 ish) ones are "switch mode" and make clean DC so they can run all your rig's systems with no battery attached at all. (The trailer still needs a battery when being towed to run the break away brakes.)