Yes and No, yes, they can, but right now, it requires some form of external control (like a Pi, or other central control source), but @wizard has some ‘one PB to rule them all’ development in mind that I suspect will happen relatively soon
As for voltage: The PB’s run on 5v, not 12v
Given you likely have 12v for the vehicle already, adding 5v to power the PB(s) could be as simple as a USB power adapter.
you could also just add one of these:
and then one controller (likely the v3) could power all of your strips.
You could use the Picos for more ‘portable’ LED things running off 5v (USB) batteries, like HulaHoops, Lamps, and the like. Imagining a few lanterns that light in sync with the car, but aren’t actually connected to the car…