Something like that is possible, but you'd have to probably build your own battery and power circuitry; most USB power packs shut off after a few minutes without any current draw, and you need to press a physical button to turn them back on.

The AUKEY supply I'm using goes for about 6 days, continuous.

You can also have two packs and judiciously swap them out every week or so. That's my plan for a video I want to record later this year.