Not my video: Just posted for future reference.
The US version Juke uses any brand CR2025 coin battery. Mine had a Sony in it and I replaced it with a Duracell.
Your first indication of the battery running out of power is when the Intelligent Key System Warning Light on the dash starts blinking in "green". You'll still have a week or so to use the Intelligent Key.
Battery Icon blinking green indicating low Intelligent key battery in remote:
Changing the battery:
What happens when the Intelligent battery dies and you haven't changed the battery? Not Juke specific but it works for Intelligent Keys.