Hey /Out/

Gone camping a few times now with some friends and this year seems to be in an absolute isolated forest area, which should be fun.

However, this time there will be no electrical outlets nearby, and I was in the market for a high mAh portable battery that I can take with me to charge my stuff, like phones for example, also, is there any out there that are on the smaller size but have an outlet built into the battery itself? as well as usb charge ports

Also, is there a portable battery that you can get where you can swap out the battery when depleted? like AA batteries, converted energy to charge your iphone?