Solar Ammo Can

by Ben N on March 2, 2018


With my recent work in solar, quite a few people have started asking me about designing small BATTERY-based solar systems.

I thought it would be nice to work on a project demonstrating basic solar battery charging principals, and at the same time, have a handy and useful project when I was done. Thus, the Solar Ammo Can was born!

I chose to use a 50 caliber plastic ammo can/storage container. It’s a nice size, has a sturdy handle on top, and is weather-proof. I’ve used a lot of these same containers as tool boxes and for storage. They are great for camping supplies.

Here’s an overview of the project and what it does.

Of course, actually assembling the project is a little more complicated. On the other hand, I really did mostly use off-the-shelf parts (or mail order at worst!) I did that to make sure that the project would be made from straight-forward components anyone could get. Here’s the step-by-step assembly video, followed by the list of components.

For this project, we used:

MTM 50 Caliber Ammo Can

Sealed Lead Acid Battery, 15AH capacity ​

20A Solar Charge Controller

Four In One Socket Panel

Banana Jacks

12 AWG stranded wire in both black and red (From local hardware store)

Crimp on electrical terminals,

spade and 1/4″ ring terminal

Silicone adhesive or hot glue

Industrial type hook and loop fastener (Velcro)

Wire Nuts or Wago (Brand) Lever Lock Nuts.

Fuse Holder and Fuse.

6-32 and 8-32 nuts, bolts, and washers

PV Solar panel. Any 12V nominal solar panel of about 10 to 20 watts is perfect for this project. Here’s one which looks affordable, and it about the right size and style for the project.

DC Power Adapter (Wall Charger) Any DC wall power adapter of higher than 12V (13.2, 14.4, 18) and one amp will work fine. I already had a 18V 1.3A power adapter handy. Here’s a similar adapter.

USB Gooseneck LED Light These small USB lights work great. They are very simple and durable. Fantastic for camping.

100 Watt AC Power Inverter. This device converts DC power to AC power so that you can run typical household devices from a battery. A 100 watt version is very compact and inexpensive. I already had one, which I used for this project. Here is a similar version.

Once I had all the components, it was just a matter of laying them out and fitting them all in the box. Rather than drilling through the side of the ammo can (and wrecking the weather-proofness!) I decided that all the components should go INSIDE the box. To do that, I’d have to make some sort of a faceplate for the parts to mount to. I scanned the components so that I could bring them into a vector graphic program where I could arrange them, and then use that to make a cut file for a laser-cutter. I then visited a friend, and used his laser cutter to make the faceplate.

Due to many requests, we’ve made the laser-cut solar ammo faceplate available for sale. See it here:

Assembling the components to the faceplate is just a matter of putting components through the holes and adding a few screws, nuts, and washers.

For the electrical, I just followed the schematics on the Solar Charge Controller and the Four-in-One socket panel. The main thing to remember is that all the power goes through the solar charge controller. Besides controlling the charge, this device also acts as a low-voltage cut-off to prevent loads from over-discharging the battery.

A main fuse is connected between the solar charge controller and the Positive side of the battery. I used a 20A fuse, as the charge controller and other components are all rated at a maximum of 20A.

Wiring was completed with 12 awg stranded copper wiring, color coded red for positive and black for negative. Wago lever locks are nice connectors that can take the place of wire nuts. They make solid connections, but also allow you to add another wire later, or remove one. They are great for prototyping projects!

I glued down the battery inside the ammo can and placed a piece of self-adhesive industrial Velcro on top of the battery. A matching piece of Velcro went on the back of the faceplate. After plugging in the battery wires, I simply Velcro’d down the faceplate over the top of the battery.

At that point, the Solar Ammo Can is ready for action! It’s handy for camping and emergencies. The Solar Ammo Can will charge a phone or tablet, run a light or radio, and can even run low-power AC devices. The Solar Ammo Can weighs less than 10 lbs, and cut easily be lifted and carried by nearly anyone.

I already had a solar panel appropriate for this project. I looked around to see what’s out there for an affordable panel that would match and found this one.
Here’s my video review and how to use it.

If you haven’t already, please take a look the YouTube videos, and feel free to comment either at the video on YouTube, or right here at
As always, please like, share, and subscribe!

Until next time, stay charged up!


{ 5 comments… read them below or add one }

1 Tadeu Carlos Marques November 3, 2019 at 2:57 pm

I would like to know where I find the instructions to properly connect the cables to each other, as there is no such instruction in the videos

2 Tim Record September 15, 2020 at 4:18 pm

I followed the instructions, plugged everything up like photos you posted but can’t get the switch to work properly. When the switch is off and I connect the battery, nothing happens. No power whatsoever to the four position connector. But, when I turn the switch on and then plug up the battery, it works fine. I’ve tried two different switches and get the same result. Would you please DM me so I can troubleshoot it?

3 admin September 15, 2020 at 4:52 pm

I showed two different ways to wire up the switch.
One of those two ways works exactly as you describe. That kills all the power when you aren’t using the ammo can.

Take a look at the diagram on the box that came with your 4-in-1 port for the simple way of having it wired up.

4 McKay February 1, 2021 at 11:32 pm


Thanks so much for this project. It’s been awesome! As far as making sure the controller is setup correctly to not overdraw or overcharge the battery did you just keep the default settings on the charger?


5 admin February 2, 2021 at 5:53 pm

I believe that the default low-voltage disconnect on that particular controller is too low.
I’d suggest actually setting the LVD to 12.0V
That’s about half the capacity of the battery. Not discharging your battery more than half way really helps keep its life from being cut short.
Here’s some more good tips on 12V systems –

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