#21700 power-pack challenge

You only find out how many pitfalls there are once you build your own FPV drone packs: the negative side of tabless 21700s is really current-hungry — I had to push the UF20B to gear 52 to get full penetration. Paired it with a 40A BMS and measured every cell's internal resistance before welding; max spread 2mΩ. Flew three packs, and the shell wasn't hot when I touched it after landing. Happy. The recipe is attached to the project. Judges, please go easy on me.