I started out with a want of making a battery pack for my Google mini which i could recharge and easily take out on the deck, etc. I found the original by Hopo28, and just thought i wanted something different. This is what I came up with, I also included a spreadsheet with parts, wire lengths, printing times (as much as I could for my equipment - Snapmaker) wire lengths, etc. When I printed the tops for covering the circuit boards, I made it for quantity, and added a raft which seemed to get the best quality for my system. The only circuit board glued down is the charging circuit, and i added a drop of glue to the Voltage amplifier to ensure the value didn't change (5V) while assembling it. I used an earlier version and it last for 6 hours at 75% volume. Edit: I made the battery pack so that the batteries could be replaced if needed, and so that i could ship them via ground at the US Post Office (They have to be removed to ship). Enjoy.
FYI, this was a group effort with assistance from Hopo28 and Paulbacca to name a few.
4/2/2019 Added a new Bottom that has a larger switch hole for mounting on the outside.