Go with a battery maintainer/tender that is smart enough to stop the charge when the battery is fully charged so it can be left plugged in continuously. A trickle charger is not smart and if left on could damage the battery, it needs to be disconnected when the battery is charged. I permanently installed a battery maintainer, mounting it with a couple short self-tapping screws onto the top of the air filter box.
This is what I chose, it has been working fine for just over 7 years.
https://www.amazon.com/gp/product/B0000AXTUY/?tag=wranglerorg-20