EC Technology 22400 mAh Battery pack holder

Long story short, I built a Stratux ADS-B receiver to use in my airplane on cross country's. I did not want to use any type of DC-DC converter to power the unit; but I came across a gentleman on YouTube that was using a EC Technology 22400 mAh Battery pack , or several maybe using it. Anyway, I did not want to introduce any more high frequencies in to electrical system.

Battery Pack:

https://www.ecgadgets.com/collections/power-banks/products/22400mah-external-battery-black-red?gclid=CJ