Dash Cam Power other than car battery?

Thinking of buying a dash cam, for example Nextbase 622GW 4K. Are dash cams required to be powered from your car battery, or can you buy separate batteries specifically to power the dash cam? If yes, what kind of battery should I buy? I‘d like to be able to switch the dash cam between cars. And don’t want to mess hooking up with my cars’ battery systems. Thank you for any input.