Milwaukee M18 Carry-On Power Supply Review

Milwaukee Provides Portable Jobsite Power With M18 Carry-On Power Supply

Portable power is no stranger to construction sites. However, the challenge of using a battery (or batteries) to power corded tools is. Milwaukee answered that challenge initially with the MX Fuel Carry-On Power Supply. Now, they turn to its massively popular 18-volt system with the Milwaukee M18 Carry-On Power Supply. We’re diving deeper into the design to see what it is… and what it isn’t.

Pros

• Power to run 15-amp corded tools
• Durable, jobsite-ready design
• Pure sine wave output
• Includes 120V AC, USB-A, and USB-C outlets
• Simultaneously charges four batteries
• Compatible with any M18 batteries

Cons

• Not as feature-rich as recreational power supplies
• Lowest-capacity pack limits the runtime

Milwaukee M18 Carry-On Power Supply Performance

Power Source

To power this unit you need four M18 batteries. That’s different from some of the other exterior battery units that step down the watts with lower numbers of batteries. It makes sense, though. You’re not going to run a 2-inch rotary hammer very long if you only slap a single 2.0Ah battery on there. By requiring four batteries, Milwaukee ensures that you have the performance to run power-hungry tools with relevant runtime and it protects the packs by allowing them to share the load.

To get the best performance, make sure you start with four fully-charged batteries of the same capacity. Whichever pack drains first limits your runtime.

As you get close to the end of your runtime, the unit emits a beep that’s loud enough to be heard on a jobsite. However, its standard operating noise level is just 66 decibels.

Output

As for output, the Milwaukee 2845 offers 3600 starting watts and 1800 running watts of pure sine wave energy to power everything from sensitive electronics to 15-amp corded tools. That’s the same as what the MX Fuel unit offers. The output is significantly more than some of the portable power stations in a similar size range. For example, the Jackery 1000 offers just 1000 running watts. The Generac GB1000 and GB2000 are better at 1600 watts, but still short of what you get from Milwaukee.

It’s A Charger

Another notable feature is the ability to charge your M18 batteries simultaneously at a standard 3A rate using the included charging cord.

Note that the outlets aren’t active until you press the power button. When you do, charging stops, even if it’s still plugged into the wall.

Applications

With the Milwaukee M18 Carry-On Power Supply, you get a pair of 120V AC outlets, a USB-A port, and a USB-C port. For tools, you can run 15-amp tools like table saws and compressors. Its pure sine wave energy also enables you to charge sensitive electronics like your phone or laptop.

That’s not all, though. When Hurricane Ian rolled through, we used it to power a full-size refrigerator overnight and to smoke chickens on our Traeger pellet grill. Basically, if you can plug it into a standard wall outlet, the Milwaukee 2845 can run it. Plus, it doesn’t matter if you need to run it inside or outside—there are no gas fumes or smells to worry about.

Milwaukee M18 Carry-On Power Supply Design Notes

What It Isn’t

I talked to a friend who felt Milwaukee punted on this unit, which confused me a bit. What he wanted to see was an LCD screen that showed charging and discharge rates, solar compatibility, and more outlets. In other words, he wanted a recreational portable power supply.

That’s not what Milwaukee primarily designed this unit for, though. It’s first and foremost for power tools and electronics on a jobsite. That’s why it has a roll cage design and optional battery locks. While having the additional feedback on a screen is helpful, it’s at risk of breaking more easily than other components and the information it provides isn’t something you’d monitor as closely on-site. In our opinion, the 4 LED lights and notification beeps do the job well enough.

Size and Weight

Without batteries, the Milwaukee 2845 weighs 28 pounds. By the time you add four 12.0Ah High-Output packs to the mix, it’s 41.7 pounds. Its footprint takes up 15.1 inches long, 12.3 inches wide, and 13.8 inches tall.

Additional Features

• Recommended operating temperature: 32° – 105° F (40° – 105° recommended charging temperature)
• Compatible with shoulder strap (sold separately) for easy carrying
• Compatible with all M18 batteries

Milwaukee M18 Carry-On Power Supply Price

The Milwaukee 2845 retails for $699 bare and there are a couple of kit options available. With four 5.0Ah batteries and the shoulder strap, it’s $1122. It’s a good option if you’re primarily charging devices and/or running tools with lower power demands.

There’s also a kit with four 12.0Ah High Output batteries and the shoulder strap for $1720. This gets you the longest runtime and it’s what we suggest if you’re running tools on the higher end of the power scale.

Milwaukee backs this device with a 3-year limited warranty.

Milwaukee M18 Carry-On Power Supply Quick Comparison

The Bottom Line

The primary goal of the Milwaukee M18 Carry-On Power Supply is to supply power to your corded tools, including in environments you can’t run a gas generator in. However, it’s not designed with all of the features you might find on a recreational portable power supply. For what the product team designed the 2845 to do, it does well. Buy it if you need a battery-powered construction site power supply and enjoy that you can use it recreationally as a secondary application.

Specifications

• Model: Milwaukee 2845-20
• Length: 15.05 in
• Width: 12.25 in
• Height: 13.75 in
• Weight: 28 lbs (without battery)
• Noise level: 66dB(a)
• Starting watts: 3600W
• Running watts: 1800W
• AC output: 120V 15A Duplex
• DC output: USB-A Port: 5V. 2.1 A (10.5W)
• USB-C PD Port: 5/9/12/15/20V, 3A (60W)

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