4S7P Li-ion 18650 Field Pack

thingiverse

Here's a portable Li-ion battery pack built around a standard 50Cal Ammo Box. It carries a set of 28 high-capacity 18650 cells, which I purchased for approximately £50 to build. This innovative design enables me to recharge multiple batteries while out flying. The pack can hold an additional 12-15 1300mAh Li-po packs, providing extended power supply in the field. A clever aspect of this setup is its modularity - two robust zipties secure the battery pack's components together, allowing for effortless disassembly and reassembly as needed. However, it's essential to note that this design does not incorporate a BMS (Balance Management System). As such, users will require a dedicated balance charger to ensure proper charging and maintenance of the cells.