I've stopped using the big bulky battery packs. Instead I use 2 extremely light systems that use replaceable batteries.
I take either the Nitecore F2 or
Amazon.com: Weltool Magnetic USB Battery Charger Universal for Li-ion Battery Portable Charger for Travelling, Compatible with 26650 21700 20700 18650 18350 16340 Rechargeable Battery Charge Discharge Refresh LIB: Home Audio & Theater
www.amazon.com
Combine them with your choice of batteries. I use a combo of 18650, 20700 and 21700.
At the weight of these systems, I can take both. I can change what I take depending on the trip. , I'll take the magnetic charger and a single 21700, 2.9ounces and enough capacity to charge every single electrical device I have. Ten day, it's less then 14 ounces and I'll have capacity to spare.
Total system weight is less then the larger battery packs from Anker (which I have a couple of) for the same level of storage capacity. Easily waterproofed in a tiny stuff sac.