For most Milwaukee M18 tools, the REDLITHIUM XC 5.0 Ah battery is the right starting point. Move up to 8.0 Ah or 12.0 Ah for power-hungry tools like saws and grinders, or when you want to work a full day without swapping batteries.
The M18 platform has several lineups (REDLITHIUM, FORGE) and capacities from 2.0 to 12.0 Ah, which makes the choice less obvious than it looks. This guide compares the models in our Milwaukee batteries collection, then explains which charger to pick, including the Milwaukee M18 and M12 multi-voltage charger 48-59-1812, which charges both platforms.
Équipement Polar is a Milwaukee tool retailer in Quebec City and Chicoutimi. The prices below are those on our product pages at the time of publication.
Our Quick Picks
- Starting point → Milwaukee M18 REDLITHIUM XC 5.0 Ah battery : $119
- One step up → Milwaukee M18 REDLITHIUM XC 6.0 Ah battery : $188
- High capacity at a better price → Milwaukee 18V FORGE XC 8.0 Ah battery : $348
- Maximum runtime → Milwaukee 18V FORGE 12 Ah battery : $448
- New M18 fleet → Milwaukee M18 5.0 Ah starter kit (2 batteries and charger) : $309
Comparison table of Milwaukee M18 batteries
| Model | Lineup | Capacity | Price CAD |
|---|---|---|---|
| 48-11-1850 | REDLITHIUM XC | 5.0 Ah | $119 |
| 48-11-1865 | REDLITHIUM XC | 6.0 Ah | $188 |
| 48-11-1881 | FORGE XC | 8.0 Ah | $348 |
| 48-11-1880 | REDLITHIUM | 8.0 Ah | $399 |
| 48-11-1813 | FORGE | 12 Ah | $448 |
| Starter kit | REDLITHIUM XC | 2 x 5.0 Ah and charger | $309 |
Prices in Canadian dollars at the time of publication. Check the price and stock on the product page. Free shipping on orders over $150 everywhere in Canada from equipementpolar.com.
Understanding the M18 platform
M18 and M12: two separate platforms
M18 refers to Milwaukee's 18V tools and batteries, M12 to its 12V ones. The two platforms are not interchangeable: an M18 battery goes on an M18 tool, an M12 battery on an M12 tool. The 48-59-1812 multi-voltage charger charges both types of batteries, but they remain different batteries.
REDLITHIUM and FORGE: two lineups
The REDLITHIUM lineup is the base of M18 batteries, with REDLINK Intelligence technology that lets the battery, the tool and the charger communicate. In this selection, the FORGE lineup covers the 8.0 XC and 12 Ah models: according to Milwaukee's product pages, it aims for high energy density, and the 12 Ah model adds a COOL-CYCLE active cooling system.
What amp-hours really change
Capacity in amp-hours (Ah) mostly determines how long the tool runs between charges. An 8.0 Ah battery has 60% more capacity than a 5.0 Ah. In return, higher capacity costs more: from $119 for the 5.0 Ah to $448 for the 12 Ah.
1. Milwaukee M18 REDLITHIUM XC 5.0 Ah Battery (48-11-1850)
The starting point for any M18 tool fleet. If you only buy one battery, this is the one.
The XC 5.0 Ah is the most affordable M18 battery in this selection. According to Milwaukee, REDLITHIUM XC technology delivers up to 2.5 times more runtime than a standard lithium-ion battery, in a build with an internal metal frame and a shock-absorbing rubber overmold.
For an electrician, carpenter or contractor equipping everyday tools (drill, impact driver, reciprocating saw), it is the reference: enough reserve for a good part of the day, without paying for capacity you will not use.
Pros
- Lowest price in the selection: $119
- Internal metal frame and shock-absorbing base
- REDLINK Intelligence between the battery, the tool and the charger
Things to consider
- On a power-hungry tool used all day, higher capacity means fewer battery swaps
- Less reserve than the 8.0 and 12 Ah models
Ideal for: First M18 purchase, everyday tools, a fleet of several batteries at a good price.
Not ideal for: Full days on a power-hungry tool: see the FORGE 8.0 or the FORGE 12 Ah.
Price: $119
View the XC 5.0 Ah at Polar →2. Milwaukee M18 REDLITHIUM XC 6.0 Ah Battery (48-11-1865)
One step above the 5.0 Ah, in the same lineup and on the same platform.
The XC 6.0 Ah offers 20% more capacity than the XC 5.0 Ah, for $69 more. It suits those who find the 5.0 Ah a little tight without wanting to move up to the price of the 8.0 Ah models.
The product page states it is designed for all tools in the M18 range, including in harsh Quebec winter conditions.
Pros
- 20% more capacity than the XC 5.0 Ah
- Same REDLITHIUM XC lineup and same REDLINK Intelligence
- $160 cheaper than the FORGE 8.0 Ah
Things to consider
- $69 more than the XC 5.0 Ah for 1.0 Ah more
- The capacity gap stays modest if you aim for a full day on a power-hungry tool
Ideal for: Users who find the 5.0 Ah tight, mixed job site and shop use.
Not ideal for: Tight budget: the XC 5.0 Ah covers most uses. Maximum runtime: see the FORGE 12 Ah.
Price: $188
View the XC 6.0 Ah at Polar →3. Milwaukee 18V FORGE XC 8.0 Ah Battery (48-11-1881)
The high capacity of the FORGE lineup, at a lower price than the REDLITHIUM 8.0 Ah.
The FORGE XC 8.0 Ah offers 60% more capacity than the XC 5.0 Ah. According to Milwaukee's product page, FORGE technology maximizes energy density while keeping a compact, balanced format.
As a price reference, the REDLITHIUM 8.0 Ah battery (48-11-1880) costs $399 in our collection, $51 more than this FORGE XC 8.0 Ah. Compare the two product pages to see the lineup differences.
Pros
- 8.0 Ah for $348, $51 less than the REDLITHIUM 8.0 Ah
- 60% more capacity than the XC 5.0 Ah
- Format described as compact and balanced, at 1.2 kg per the product page
Things to consider
- $229 more than the XC 5.0 Ah
- Hard to justify for light tools or occasional use
Ideal for: Long days on power-hungry tools, crews that want fewer charging stops.
Not ideal for: Occasional use or compact tools: the XC 5.0 Ah is enough.
Price: $348
View the FORGE XC 8.0 Ah at Polar →4. Milwaukee 18V FORGE 12 Ah Battery (48-11-1813)
The largest capacity in the selection, for the most demanding job site days.
The FORGE 12 Ah is the highest-capacity M18 battery in this selection, more than double the XC 5.0 Ah. It is sold individually and includes the COOL-CYCLE active cooling system, which aims to reduce downtime by keeping the battery at a good temperature.
It is aimed at crews that work all day on energy-hungry tools, without easy access to a charger.
Pros
- Highest capacity in the selection: 12 Ah
- COOL-CYCLE active cooling
- Fewer battery swaps over a long day
Things to consider
- The most expensive in the selection: $448
- Heavier than the other models in the selection: 1.5 kg per the product page, versus 726 g for the XC 5.0 Ah
Ideal for: Intensive job sites, power-hungry tools, crews far from an outlet.
Not ideal for: Light tools or occasional use: the capacity would never be used.
Price: $448
View the FORGE 12 Ah at Polar →5. Milwaukee M18 5.0 Ah Starter Kit (2 Batteries and Charger)
To start an M18 fleet: two 5.0 Ah batteries and a charger in one purchase.
Two 5.0 Ah batteries sold separately cost $238. The $309 starter kit therefore adds the charger for $71 more. According to the product page, the 2-port charger charges both batteries at the same time and brings them to full charge in about 1 hour.
It is the logical option to start an M18 fleet: one battery works while the other charges.
Pros
- Two batteries and a charger in a single purchase
- Simultaneous charging of two batteries
- A spare battery while the other charges
Things to consider
- Charger designed for 18V batteries: it does not charge M12 batteries
- For a mixed M12 and M18 fleet, the 48-59-1812 charger is more versatile
Ideal for: First M18 tool, new employee to equip, full replacement.
Not ideal for: A fleet that already has several batteries and a charger: buy the battery alone.
Price: $309
View the starter kit at Polar →Need help choosing?
Our advisors in Quebec City and Chicoutimi know every model in this selection. Free advice, in-store or over the phone.
Contact our experts See the Milwaukee batteries collection →Which charger with which battery
The Milwaukee M18 and M12 multi-voltage charger 48-59-1812 replaces two chargers with one. It charges batteries one after the other, in the order you insert them, and monitors cell voltage and temperature. According to the product page, charging takes about 30 minutes for a compact battery and about 60 minutes for a high-capacity battery.
It runs on a 120 V AC outlet, is sold without a battery and costs $35.71. The product page mentions a 5-year limited manufacturer warranty.
| Charger | Compatible | Charging mode | Price CAD |
|---|---|---|---|
| 48-59-1812 (sold on its own) | M18 and M12 batteries | Sequential, one battery at a time | $35.71 |
| Starter kit charger | Milwaukee 18V Li-Ion batteries | 2 ports, simultaneous charging | Included in the $309 kit |
If you switch between M12 and M18 tools, the 48-59-1812 saves you from having two chargers on the bench or in the truck. If you only work with M18 and often charge two batteries at once, the 2-port charger in the starter kit is faster.
Which battery to choose based on your usage
You use compact tools or do finishing work
The XC 5.0 Ah is enough. It costs $119 and covers most everyday uses. No need to pay $448 for capacity that will go unused.
You work on a job site all day
Prioritize capacity. The FORGE XC 8.0 Ah ($348) or the FORGE 12 Ah ($448) reduce the number of battery swaps. Two mid-capacity batteries and a charger within reach can also do the job, depending on your tools.
You work outside in Quebec winters
The product pages in our collection state that REDLITHIUM batteries operate down to -18°C. Plan for a spare battery in addition to the one on the tool, whatever the capacity.
You are starting a new M18 fleet
The $309 starter kit (two 5.0 Ah batteries and a charger) is the simplest entry point. You can then add higher-capacity batteries for the tools that need them.
You have both M12 and M18 tools
The batteries are not interchangeable, but the 48-59-1812 charger at $35.71 charges both platforms.
Practical tip: the model number (48-11-XXXX) is the only reliable way to tell batteries apart. The "M18" label alone says nothing about the lineup or the capacity: check the exact model before ordering a replacement.
Ready to choose your Milwaukee M18 battery?
Équipement Polar sells Milwaukee tools and batteries in Quebec City, Chicoutimi and across Canada. Free shipping on orders of $150 or more. Where to buy Milwaukee tools in Canada.
See Milwaukee batteries → See the M18 and M12 charger →FAQ: Milwaukee M18 Batteries
No. M18 and M12 are two separate platforms, 18V and 12V. An M18 battery goes on an M18 tool and an M12 battery on an M12 tool. Only the 48-59-1812 multi-voltage charger charges both types of batteries.
The XC 5.0 Ah ($119) is the starting point for most uses. For full days on power-hungry tools, the 8.0 Ah models ($348 in FORGE XC) and the 12 Ah ($448) reduce the number of battery swaps.
REDLITHIUM is the base lineup of M18 batteries, with REDLINK Intelligence. FORGE covers the 8.0 XC and 12 Ah models in our selection. According to Milwaukee's product pages, it aims for high energy density, and the 12 Ah model adds COOL-CYCLE active cooling. Compare the product pages for details.
Yes, with the 48-59-1812 multi-voltage charger. It charges batteries one after the other, in the order you insert them.
With the 48-59-1812 charger, about 30 minutes for a compact battery and about 60 minutes for a high-capacity battery, according to the product page. The 2-port charger in the starter kit charges its batteries in about 1 hour.
Équipement Industriel Polar sells Milwaukee M18 batteries in-store in Quebec City (3425 Bd Wilfrid-Hamel) and Chicoutimi, or online at equipementpolar.com. Free shipping on orders over $150, anywhere in Canada in 2 to 5 business days.