Ammo Can Battery; 50 Ah LiFePO4 Clad In Army Green

March 30, 2020 by Mike Szczys 23 Comments

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 LiFePO₄ cells wired in series to achieve a nominal 12 V supply that stands in for a traditional lead-acid battery. The angel of second-hand purchases was smiling on this project as the cells were acquired on eBay in unused condition, complete with bus bars and mounting spacers. All it took to fit them in the case was to grind off the spacers’ dovetails on the outer edges.

There are many benefits to Lithium Iron Phosphate chemistry over traditional lead acid and [Kenneth] spells that out in his discussion of the battery management system at work here. While the newer technology has a much better discharge curve than lead-acid, there’s a frightening amount of power density there if these batteries were to have a catastrophic failure. That’s why there are Battery Management Systems and the one in use here is capable of monitoring all four cells individually which explains the small-gauge wires in the image above. It can balance all of the cells to make sure one doesn’t get more juice than the others, and can disconnect the system if trouble is a-brewin’. Continue reading “Ammo Can Battery; 50 Ah LiFePO4 Clad In Army Green” →

Ammo Can Holds A 14,000 Lumen LED Flashlight

March 28, 2019 by Tom Nardi 10 Comments

For most people, a flashlight is just something you keep in a drawer in the kitchen in case the power goes out. There’s even a good chance your “flashlight” is just an application on your phone at this point. But as we’ve seen many times before from mechanical keyboards to Power Wheels, hardcore niche communities can develop around the most innocuous pieces of hardware; and the lowly flashlight is no different.

Case in point, this 14,000 lumen LED flashlight built by [Bryson Hicks]. Designed around a 100 watt module from Stratus LED, the flashlight uses a number of 3D printed components to make itself at home in a suitably hardcore enclosure: a metal ammo can. With the addition of some modular electronics and a rather slick little control panel, his light is ready to deliver an unreasonable level of brightness anywhere he wishes.

The Stratus LED module includes its own driver, and just needs to be hooked up to a suitably beefy power source to do its thing. [Bryson] went with a 4500 mAh LiPo battery that he says gets him about a one hour runtime at full brightness. For somewhat less intense operation, he’s added a potentiometer which interfaces with the module’s driver board to control the LED output. Considering how fast the light sucks down the juice, adding a small LCD battery charge indicator to the top of the device seems like it was a prudent decision.

To prevent you from cooking anyone’s eyes at close range, the light requires you to first “arm” it by flipping the military style protected switch. Once the switch is in the on position, an illuminated push button is used to actually turn the LED module on and off. You can also snap the toggle switch back into the closed and covered position if you needed to kill the light in a hurry.

This isn’t the first preposterously bright LED flashlight we’ve seen around these parts. There’s something of an arms-race between hackers and makers to develop increasingly bright lights they can carry around, on the off chance they need to illuminate an entire neighborhood.

A Custom, Workshop Squeezebox

May 1, 2015 by Brian Benchoff 3 Comments

Launched over 10 years ago, the Squeezebox was one of the most popular network streaming devices sold. The idea was simple: put some MP3s on a computer, connect the Squeezebox to a LAN, and stream those tunes. Someone at Logitech had the brilliant idea that MP3s and other audio files should be stored in an online service a while back, something that didn’t sit well with [Richard]. He went out and built his own Squeezebox with a Raspberry Pi, out of an ammo box, no less.

Most of the project is based on another Squeezebox Raspi mashup over at Instructables. This was a wall-mounted project, and not encased that keeps 7.62 ammunition secure during transport. It did, however, provide enough information for [Richard] to use in his project.

To make his Squeezebox look a little more industrial and sturdy, he cut a few holes in a NATO ammo can for speakers, a TFT touchscreen display, and a USB charger port. Inside, a pair of powered speakers, a USB hub, and a powerbank were added, making this a portable streaming solution that can take a beating.

12V Ammo Power Box Keeps It Retro

January 26, 2014 by James Hobson 10 Comments

[Brandon Fiquett] does a lot of amateur radio communications and needed a rugged portable power supply that he could take with him on the road. 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 sanded it, re-painted it, and lubricated the rubber seal. Inside, he loaded it with four 7.1Ah sealed lead acid batteries, complete with 12V cigarette fused sockets, banana plug jacks, a 5V USB charger and an integrated 12V lead-acid battery charger. The lid also features an LED strip light, and everything is laid out very nicely inside of the box. It looks great, but [Brandon] has a long list of improvements to add, including a solar charge controller, volt and amp meters, and an LED power switch.

Ammo cans make solid project boxes. We’ve seen countless ammo can speaker setups, and even a more intricate ammo can PSU — though we prefer [Brandon’s] method since all the connections are under the lid, keeping it completely weather proof.