No, you will not have to set up the lock again after changing or charging the battery.
You simply place the battery back in the lock and slide the cover back on. It could take up to 1 minute for the lock to reboot and show up online.
If after about 1 minute the lock does not show online, try manually locking and unlocking by turning the lock thumb turn.
If after the troubleshooting, the lock still does not show online, please open a support ticket here and our Array Care Team will help you.