Milwaukee M18 Compact vs XC Batteries

Difference Between Milwaukee M18 Compact & XC Batteries

Milwaukee Tool has some pretty advanced battery technology and offers this in two sizes: the Milwaukee M18 Compact vs XC Batteries (eXtra Capacity). But is there a difference? It turns out there is. Both of the M18 lithium-ion battery packs offer increased run-time with up to 40% less weight than typical 18V NiCd batteries. Both contain Milwaukee’s Digital Power Management System, which helps to ensure that optimal battery life and run-time are achieved while protecting the battery and tool during tough jobsite applications. Let’s face it, we’ve all abused tools, so when Milwaukee added overload protection into the battery to prevent the tool from frying the motor or overloading the battery by drawing too much current when being abused (*cough, mixing thin-set, *cough) we knew we had reached a new era of “smart” batteries.


Editor’s Note: Check out our articles on Milwaukee battery warranty periods as well as Milwaukee RedLithium battery technology.

Milwaukee M18 Compact vs XC Batteries

To illustrate just how far we’ve come, realize that each M18 lithium-ion battery comes with a temperature management system to keep the battery in an ideal temperature range and individual cell voltage monitoring to help ensure optimal charging and discharging. It’s features like these that help assure consumers that these new batteries are much more than dummy cells that have a one-year shelf life. In fact, M18 batteries are built with discharge protection, solving one of the main problems with both NiCd and NiMH and preventing cell damage from over-discharging the battery.

Each M18 battery, including both the Compact and XC models, comes with an integrated battery fuel gauge. It’s a small membrane button that activates up to 4 LED lights on the front of the battery, telling the user the remaining run-time for the battery pack. If an old NiCd were a trusty compass, these lithium-ion batteries would be the equivalent of a GPS.

Milwaukee M18 Compact vs XC Batteries

Smart M18 Compact Batteries?

With all this technology, it’s no wonder we call these batteries “smart.” Rather than use a completely universal shoe connection for all lithium-ion batteries, consumers will note that the Compact battery actually has an additional raised molded detent (whereas the XC only has one). This physically prevents the Compact battery from being inserted into incompatible tools.

What this means is that you can’t insert a Compact battery into the M18 SawZall, for example. This is done to protect users from damaging the tools by overworking the motors to compensate for lack of power, plus it ensures a better user experience (can you imagine trying to power a power-hungry cordless tool with half the capacity?).

This physical battery barrier, along with the 5 electrical connection points (unusual for a DC-powered device), uses electronics and sensors so that a hybrid-battery tool, like the hammer drill, can know which battery is in and adjust the torque accordingly.

Full Compatibility with Milwaukee M18 Tools

Per Milwaukee, the M18 Compact battery (48-11-1815) works only on the following tools (expect this list to grow as the company adds more tools):

  • 2601 – Cordless Drill/Driver
  • 2602 – Cordless Hammer Drill/Driver
  • 2632 – Cordless ProPEX Expansion Tool
  • 2650 – Cordless 1/4″ Hex Compact Impact Driver
  • 2651 – Cordless 3/8″ Compact Impact Wrench
  • 2652 – Cordless 1/2″ Compact Impact Wrench
  • 2625 – Hackzall Cordless One-handed Reciprocating Saw
  • 2790 – Jobsite Radio
  • 0880 – Cordless Wet/Dry Vacuum
  • 2735 – LED Worklight
  • 2710 – AC/DC Wall and Vehicle Charger
  • 49-24-0171 – Cordless Worklight
  • 48-59-1801 – Lithium-ion Battery Charger

Every tool, however, can utilize the XC (48-11-1828) battery and gain additional run-time (and sometimes additional torque, as is the case with Milwaukee’s line of hammer-drills). In short, the differences are important, but the overall execution and concept is way cool, demonstrating that Milwaukee Tool has some very intelligent tools & batteries.

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