How long does it take to charge the battery?
That all depends on how discharged the battery is but normally a few hours.
If you are charging the battery for the 1st time out-of-the-box, we recommend allowing about 3 hours initially to get the battery sufficiently charged so you can perform the setup and get to grips with how the camera, hub and system in general works. You can always then put the camera on charge again as and when you need if you want to top it up.
Once you've added the hub and cameras to the Moobox app you'll be able to monitor the charging status via the app too, so you'll know when its ready to use again.