Songbird FX Birdcord & Battery pack?

I've seen a few YouTube videos about the new Birdcord USB to 9v cable and I was wondering if anyone had tried this out with a rechargeable battery pack yet?

I know that Pedaltrain makes the Volto, and now the Volto2, but it seems like you could do the same thing with a regular rechargeable battery pack now with the Birdcord, and you could get more mAh for less money than the Volto/Volto2.

I like the idea of avoiding the possible noise/hum from the wall outlet at various venues.
Anyway, if anyone has tried it out I'd love to hear your experiences. It seems like it'd be a great way to use my pedals and have one less plug in the wall.

Here's a link in case you haven't heard about it yet; Birdcord USB to 9V Converter Cable
 
I have a USB-A to 9v cable from Amazon that I use with a single pedal, Zoom B2, and up to 3 pedals on a daisy chain (Zoom B2.1u, Sweeper, Lo|Fat) that works great with a USB battery pack. Perfect for short drop and play sets and could certainly go longer as it does not seem to drain. I have tested my larger board and everything worked fine even with a couple of high need digital pedals.