For the price of a mid-range Android phone, [Kenneth Finnegan] turned a 50 caliber ammo can into a 50 amp-hour portable power supply. The battery pack uses four 3.5 V LiFePO 4 cells wired in ...

with an overall goal of shaving roughly 20 pounds off of the current weight of a can of .50 cal ammo, as Task & Purpose previously reported. Because polymer ammo is highly heat-absorbent, the new ...

He decided to make a 12V power supply out of an antique ammo can he found at an army surplus store. The .50 cal ammo box wasn’t in the greatest condition when he picked it up, so he completely ...