Milwaukee now offers two different M12 3.0Ah battery packs – a compact battery, and an XC battery. What’s the difference?
Somebody asked this on the Garage Journal forum, and it’s a great question. The answer can be extended to questions about other battery platforms, but things can get messy since there are more variables changing. For instance, the new Dewalt 20V Max compact 3.0Ah battery pack has larger cells than the bigger high capacity 3.0Ah battery, and so things aren’t entirely relatable.
The forum question asked about whether runtime is the same, with only the battery size changing.
While answering this requires making some assumptions in order to ignore several unknowns, hopefully my explanation makes sense. But also, please keep in mind that it’s been untested.
Background: M12 3.0Ah Compact Battery Pack
The compact 3.0Ah M12 battery pack, model no. 48-11-2430, has three lithium-ion cells.
Price: $59 for (1), $110 for (2)
Background: M12 XC 3.0Ah Compact Battery Pack
The XC M12 battery pack, model no. 48-11-2402, has six lithium-ion cells.
Price: $69 for (1), $119 for (2) – or $99 at Home Depot and during promo seasons
For light Milwaukee M12 tool usage, say driving small fasteners, powering an LED flashlight at low brightness, or powering a heated jacket at low heat, runtime should be similar.
For such uses, the compact battery pack has a small size and pricing advantage.
Heavy Duty Applications
This is where things change.
Given what I have seen in other examples, the Milwaukee M12 XC battery will have the advantage here.
Milwaukee’s XC batteries also given certain tools, mainly drills, a slight bump up in power. This has been true for M18 tools, but I don’t recall if I’ve heard of similar for M12 tools. Luckily, we know someone who recently tested things out – Doresoom Reviews.
It’s unclear as to which other tools XC batteries might provide a power or performance boost for, but there are other benefits as well.
XC battery packs have twice the number of lithium-ion cells compared to compact battery packs – 6 cells compared to 3. For light duty tasks, there’s no practical difference.
Consider heavier duty work, where the power output of a battery pack increases. The compact battery pack might inch close to its output ceiling, and its internal temperature will increase, sometimes by quite a bit. A tool might then turn off, either due to over-current or over-temperature conditions.
Again, I’d like to remind you that this is all in theory.
The power output of an XC battery pack, will also increase in power output, but there’s greater overhead before it reaches on-paper limits. The battery pack’s operating temperature might still increase, but the XC pack should run cooler than a compact battery pack that’s being taxed under the same operating conditions.
Consider a situation where two barrels have to be filled with water. To fill the first barrel, one person is transferring water with a 3 gallon container. In the other boat, two people each have 1.5 gallon containers.
Let’s say the barrels are filled with 1 gallon per minute. The barrels will likely fill at the same rate. 2 gallons per minute? The person working alone might be filling their barrel a little slower. 3 gallons per minute? The team has more of an advantage.
If you’re saying “but 3 gallons of water doesn’t weigh all that much,” let’s say 3 gallons of cement. Or sand. Who will be faster or less fatigued, one person with a 3 gallon container, or two people with 1.5 gallon containers?
I’m not certain about 1.5Ah cells, but the last I checked, 2.0Ah and 3.0Ah cells had much higher maximum current discharge rates than 3.0Ah cells. This would make the 3.0Ah compact battery pack a little more prone to running hotter at high current operation.
This, in demanding applications, an XC battery pack should last longer, with less risk of over-current or overheating protections kicking in, at least compared to compact battery packs.
Size, Weight, and Ergonomic Differences
Compact batteries are smaller and lighter than XC batteries. This can be a convenience.
XC batteries have larger flat bottoms, allowing tools to stand up on a table, floor, or other stable horizontal surface. This makes it easier or at least quicker to set down and retrieve certain tools.
The compact battery pack costs less than the XC battery, individually. Home Depot has a special on (2) packs of batteries, but the same is true for the XC battery.
If taking holiday season promo pricing into account, you can get (2) 3.0Ah XC batteries for less money than you can get (2) 3.0Ah compact batteries.
A 4.0Ah XC battery pack can be found for $69 at some retailers, $79 at others. If you’re just buying one battery, that gets you longer runtime than the 3.0Ah compact battery, for a proportionally less increase in cost.
Determining pricing advantages is tricky here. Things are somewhat close enough that pricing is probably the least important factor when comparing compact and XC batteries.
What it comes down to is what you plan to use the battery for. Will you be using it with a cordless saw? Heavy applications? Do you want to be able to set a tool down quickly, and have it at the ready for quick pickup? Or do you want your tool to be as small and light as possible?
If you want to guarantee maximum power potential, or the longest runtime in demanding use, the XC battery is likely the better bet. Stepping up to the 4.0Ah XC battery provides added advantage.
If you want to be able to set a tool down with greater stability, the XC is the better choice.
If you want a smaller and lighter tool, the compact should serve you well.
If you want the most bang for the buck, make a table and determine which battery will give you the most amp-hours of charge capacity per dollar.