Cargo Trailer LED light system for the band trailer - dual power source

Items used:
Nilight Truck Bed LED Strip Lights: https://amzn.to/3ibEU0T
Milwaukee M12 Battery Adapter: https://amzn.to/3l8BGNw
12V Single Pole Double Throw Switch: https://amzn.to/3yci4Mc
Switch Base & Face Plate: https://amzn.to/3j4VnTO
LED Upgrade for existing fixture: https://amzn.to/375oQHK
3.0 Amp Battery Upgrade: https://amzn.to/2TJaoCj

I wanted a good led lighting system for our band trailer (6x12 enclosed cargo trailer) and I couldn't find anything tested and proven to purchase. What I put together worked out perfectly so I decided to share and I hope it helps. I'm happy to answer any questions. These lights are super bright, exactly what I was hoping for, and I've had no issues with this setup.

Cost for just the Lights & battery adapter: $47 - can't beat that!
The full package, including the two 3 amp extended batteries was less than $150 - the batteries, genuine milwaukee brand, were half of that - there are generic options and smaller batteries of course.

With this setup, it's easy to charge the batteries and have a spare handy, and you can always flip the switch and run the lights from the truck (if it's running). The standard M12 batteries ran the lights for about 30 minutes (they were older and used - what I had on hand). The 3 Amp extended batteries run the lights forever - at least a couple hours, it's so long that I don't even know.

The Nilight setup came with 3 light strips, intended to light the bed of a truck. They were about 5'5" long and fit the roof ribs perfectly. The included wires were plenty long to reach, i didn't have to add any additional wiring. The extra mounting brackets came with the kit - might not have been necessary, but these being on the ceiling I didn't want them to be falling down.

A car or lawnmower battery is large and a pain to charge. The M12 battery adapter makes it super easy to charge and since I have several M12 tools & batteries I have spares all around and I can grab these from the trailer too. You should be able to find similar adapters if you use a different tool. MAKE SURE you stick with 12v though or you might blow the lights.

I cut the extra switch in so that I could run my lights from the battery or the truck. This is not required - if you want to run your lights on battery only, you can put this in as a self-contained system. I just wanted to be sure I could use the lights either way (before this upgrade, I would have to have my truck running about 30 minutes while we loaded). With this switch, the center connection goes to the lights, one side goes to the battery, and the other to the truck power (which comes through the trailer light connector). In my trailer there was a light switch by the door - so at the top of the wall I simply cut the power coming in from the truck, and put this switch. So at the top I pick my power source, and then the existing switch turns the lights on or off. The Nilight system comes with a built-in switch also and I just leave that on full time and tucked away, but if your trailer doesn't have an existing switch you could use that.

For wiring to the switch, it's easiest to crimp a spade terminal to the wire, and it slides right on the switch connectors. It's like these - https://amzn.to/2VlkfPa - but you only need 3 and can grab those cheap at a local hardware or auto supply store.

note: These are affiliate links. It costs you nothing to use those links and thank me for the info.