DeusRexy t1_j23ltxv wrote

Worked in lithium ion battery manufacturing for awhile, people in comments have already mentioned that there are smaller batteries inside the power pack, but no sizes were really told.

Each battery is different, but each of the small batteries I would say the average is something like a Capri Sun pouch, some are bigger, some are smaller. Also, they are pouches, with layered cathode and anode layers (negative/positive), with separator layers between and an electrolyte slurry inside.