What power banks are you using / eyeing on lately?
I got some no-name chink shit years ago that was 12Ah for $12. Free shipping through Amazon. It does actually supply its rated capacity too.
I dislike having one in the first place so I'm not fussed about brand or features.
xiaomi 20000mah
it's a brick but charges my s7 edge many times.
it gets charged in a long time too.
I just borrow my friends phones :^)