Comment by tbrownaw

I have some LiPo-based 1.5V AA and AAA batteries that have USB-C ports built in for charging. The AAA ones claim 1200 mWh (800 mAh) and the AA ones claim 3400 mWh or ~2250 mAh. (I say "claim" because I bought them off some random Amazon shop a few years ago and haven't bothered to actually check.)