It looks like this hasn't been visited in a while and its a topic subject to updates. Plus I'm hoping to start my section hike soon so it's relevant to me.
I've listed the specs on a few power banks. I like the Nitecore for features and weight but it's pricey. I've read good reviews and might bite the bullet if someone has a positive long term review. Otherwise I'm leaning towards to the Ravpower 15000 for a balance of power, cost, and weight. Zendure also makes some interesting models but I can find almost no reviews on them. I'm avoiding off brands.
power bank weight(oz) length(in) width height mah recharge price
RAVPower Portable Charger 20000 15.7 6.2 2.9 0.59 20000 6hrs 40.00
RAVPower Portable Charger 15000 10.2 5.53 2.8 0.81 15000 4.7hrs 33.00
Anker Powercore Essential 20000 12.1 6.2 2.9 0.8 20000 6.8hrs 40.00
Anker Solar Power Bank 19 6.88 3.46 1.19 20000 7hrs 65.00 weatherproof, solar
NITECORE NB10000 5.29 4.8 2.32 0.42 10000 60.00 dustproof, water resistant, need 2?, (have 15% off coupon)
My goal is to have my iPhone SE (new) last up to 10 days as a camera and occasional Guthooks app use. May even check for phone or text messages once in a while.
Comments and experiences welcome.
EDIT: I'm not able to format my specs very well. Sorry.
power.jpg