This person claims that one can not run a O-Pi system without modifying the charger board inside the battery to release more power at once. They claim that by changing a capacitor on the would fix it the battery to make it work.
 
I never had a problem with Power Bank Batteries powering a Pi system other than running time. In most systems, due to their power demands as a stand alone system, an hour is the norm with a 2600mah PowerBank Battery. Single Core, low running MHz/GHz clocks seem to do better than Dual Core and Quad Core Systems.
 
We've all seen my posts of running Pie system on a Power Bank Battery. It litters this forum branch! LOL! So here's their article.
 
http://uhurumkate.blogspot.com/2017/06/powering-orange-pi-zero-with-power-bank.h tml

hmm, yeah, he had transformer issues. that reading was not right for what should have been put out. It had a bad filter or no filter from the looks of it.