Cordless chainsaws are among the most demanding tools in the 18V battery family. They draw high current continuously, especially under load when cutting through hardwood or thick branches. Getting the battery choice right matters more for chainsaws than for most other cordless tools — wrong capacity and you’ll spend more time charging than cutting.
The good news is that Makita, DeWalt and Milwaukee all make batteries perfectly suited to chainsaw work. The trick is matching the right capacity to your actual cutting needs. A 3.0Ah battery will leave you frustrated on a professional job. A 6.0Ah battery transforms the experience if you’re doing serious volume work.
We’ve tested all three brands on chainsaws and compared their performance on real cutting tasks. Here’s what works best for different scenarios.
Quick Recommendations
| Use Case | Makita 18V LXT | DeWalt 20V MAX | Milwaukee M18 |
|---|---|---|---|
| Best all-round | BL1850B (5.0Ah) | DCB205 (5.0Ah) | 48-11-1850 (5.0Ah) |
| Best for heavy use | BL1860B (6.0Ah) | DCB206 (6.0Ah) | 48-11-1860 (6.0Ah) |
| Best lightweight | BL1830 (3.0Ah) | DCB204 (4.0Ah) | 48-11-1840 (4.0Ah) |
Why Battery Choice Matters for Chainsaws
Chainsaws sit at the extreme end of the 18V power tool spectrum. They demand sustained high amperage draw, especially when cutting through dense wood or when the chain binds slightly. A chainsaw that feels sluggish under load is dangerous — you lose control, the chain stalls, and you work harder to force it through the cut. The battery is what determines whether your saw feels alive or struggles.
Capacity directly affects cutting time and how many cuts you can make before swapping batteries. A 5.0Ah battery is your baseline for any serious cutting. This will give you 15–25 cuts through a 6-inch log, depending on wood type and the specific saw. A 6.0Ah battery extends this to 25–35 cuts, which makes a real difference if you’re bucking firewood or clearing storm damage. A 3.0Ah battery is emergency-only — you’ll get 5–10 cuts before needing to swap.
We strongly recommend owning at least two batteries for chainsaw work. Many professionals keep three: one in the saw, one charging, one as backup. Some Makita (DUC353) and Milwaukee (M18 F2CHS50) models use dual 18V packs for 36V operation, which doubles your runtime at the cost of double the weight.
Best Batteries for Makita Chainsaws
Makita BL1850B (5.0Ah) — Best All-Round for Pruning and Light Felling
The BL1850B strikes the right balance for general chainsaw work. Five amp-hours is enough to tackle most domestic cutting tasks without excessive weight. You’ll comfortably prune branches, cut fallen wood into burnable lengths, and handle small trees. The saw will maintain good torque throughout the discharge cycle. Makita’s 18V LXT platform batteries charge quickly and are widely available. This is the battery most Makita chainsaw owners should start with.
Buy Makita BL1850B on Amazon — Model: BL1850B
Makita BL1860B (6.0Ah) — Best for Heavy Use and Professional Work
Step up to the BL1860B if you’re cutting firewood regularly or doing tree felling work. Six amp-hours delivers 30–40% more cutting time than the 5.0Ah, which means significantly fewer battery swaps during a long day. The saw maintains better performance under sustained load. This is the battery choice for contractors and serious DIYers who expect to spend several hours cutting. Weight is noticeable but manageable with two-handed operation.
Buy Makita BL1860B on Amazon — Model: BL1860B
Makita BL1830 (3.0Ah) — Best Lightweight (Limited Use Only)
The BL1830 is genuinely too small for chainsaw work except in emergencies. Three amp-hours will give you perhaps 8–12 cuts before the battery is depleted. It’s designed for light-duty tools, not high-draw applications. Only buy this if you already own it for other tools and need occasional emergency cutting capability. For any regular use, step up to the 5.0Ah.
Buy Makita BL1830 on Amazon — Model: BL1830
All three batteries fit the Makita 18V LXT platform, including the DUC254Z top-handle and DUC353 dual-battery chainsaws.
Best Batteries for DeWalt Chainsaws
DeWalt DCB205 (5.0Ah) — Best All-Round for Pruning and Light Felling
The DCB205 is DeWalt’s sweet-spot capacity for chainsaw work. Five amp-hours delivers solid runtime for most cutting scenarios without excess weight. DeWalt’s 20V MAX chainsaws (DCCS620 12″ rear-handle) perform reliably on this battery, maintaining good cutting speed throughout the charge cycle. This is the battery most DeWalt chainsaw owners should buy first.
Buy DeWalt DCB205 on Amazon — Model: DCB205
DeWalt DCB206 (6.0Ah) — Best for Heavy Use and Professional Work
The DCB206 extends runtime significantly for high-volume cutting. Six amp-hours means roughly 40% more cuts per charge compared to the 5.0Ah. If you’re cutting firewood for winter or doing professional tree services, this is the battery that keeps you working. Weight is noticeable but the extra cutting time justifies it on longer jobs.
Buy DeWalt DCB206 on Amazon — Model: DCB206
DeWalt DCB204 (4.0Ah) — Best Lightweight for Moderate Use
The DCB204 sits between lightweight and practical capacity. Four amp-hours is light enough for extended handheld operation but delivers more cutting time than a 3.0Ah battery. This is a reasonable choice for occasional pruning and light limbing work, though we’d still recommend stepping up to the 5.0Ah for anything more demanding.
Buy DeWalt DCB204 on Amazon — Model: DCB204
All three batteries fit the DeWalt 20V MAX platform, including the DCCS620 rear-handle chainsaw.
Best Batteries for Milwaukee Chainsaws
Milwaukee 48-11-1850 (5.0Ah) — Best All-Round for Pruning and Light Felling
The 48-11-1850 is Milwaukee’s recommended baseline for chainsaw work. Five amp-hours gives good runtime for general cutting without excessive weight. Milwaukee’s M18 chainsaws (M18 FCHS) perform well on this capacity, maintaining power throughout the discharge cycle. This is where most Milwaukee chainsaw owners should start.
Buy Milwaukee 48-11-1850 on Amazon — Model: 48-11-1850
Milwaukee 48-11-1860 (6.0Ah) — Best for Heavy Use and Professional Work
The 48-11-1860 extends your cutting window significantly. Six amp-hours means 25–35 cuts through typical firewood, compared to 15–25 on the 5.0Ah. This is the battery for serious cutting work, tree felling, and professional use. Weight is manageable and the extra runtime more than compensates on longer jobs.
Buy Milwaukee 48-11-1860 on Amazon — Model: 48-11-1860
Milwaukee 48-11-1840 (4.0Ah) — Best Lightweight for Moderate Use
The 48-11-1840 is Milwaukee’s light-duty option. Four amp-hours is reasonable for occasional pruning but falls short on sustained cutting tasks. This battery makes sense if you already own it for other M18 tools and need chainsaw capability, but for dedicated chainsaw work, the 5.0Ah is the better choice.
Buy Milwaukee 48-11-1840 on Amazon — Model: 48-11-1840
All three batteries fit the Milwaukee M18 platform, including the M18 FCHS (40cm bar) and dual-battery M18 F2CHS50.
Full Comparison Table
| Battery | Platform | Capacity | Best For | Buy Link |
|---|---|---|---|---|
| Makita BL1850B | 18V LXT | 5.0Ah | General pruning and light felling | Buy on Amazon |
| Makita BL1860B | 18V LXT | 6.0Ah | Heavy use, firewood, professional work | Buy on Amazon |
| Makita BL1830 | 18V LXT | 3.0Ah | Emergency use only | Buy on Amazon |
| DeWalt DCB205 | 20V MAX | 5.0Ah | General pruning and light felling | Buy on Amazon |
| DeWalt DCB206 | 20V MAX | 6.0Ah | Heavy use, firewood, professional work | Buy on Amazon |
| DeWalt DCB204 | 20V MAX | 4.0Ah | Lightweight, moderate use | Buy on Amazon |
| Milwaukee 48-11-1850 | M18 | 5.0Ah | General pruning and light felling | Buy on Amazon |
| Milwaukee 48-11-1860 | M18 | 6.0Ah | Heavy use, firewood, professional work | Buy on Amazon |
| Milwaukee 48-11-1840 | M18 | 4.0Ah | Lightweight, moderate use | Buy on Amazon |
Frequently Asked Questions
How many cuts do you get from a single chainsaw battery?
Runtime depends on wood type, cut depth, battery capacity, and saw model. A 5.0Ah battery typically delivers 15–25 cuts through a 6-inch log of softwood. Hardwood reduces this to 12–18 cuts. A 6.0Ah battery extends this to 25–35 cuts on softwood. These are real-world figures based on standard cutting conditions — your results will vary.
What’s the minimum battery capacity for chainsaw work?
We recommend 5.0Ah as the practical minimum for any regular cutting. A 3.0Ah battery will frustrate you — you’ll spend more time swapping batteries than cutting. A 4.0Ah battery sits in an awkward middle ground; it’s better than 3.0Ah but doesn’t deliver the value jump of a 5.0Ah. Start with 5.0Ah and consider 6.0Ah if you do sustained cutting work.
Should I buy an 18V or 36V cordless chainsaw?
Some Makita (DUC353) and Milwaukee (M18 F2CHS50) models use dual 18V batteries in one pack for 36V operation. This roughly doubles your runtime and power but adds significant weight and cost. 18V is sufficient for most domestic cutting — trees under 200mm diameter, pruning, limbing, and firewood bucking. 36V is professional-grade for sustained felling and high-volume work. Choose 18V unless you’re running a tree service business.
Can I use a small 3.0Ah battery for pruning work?
Technically yes, but you won’t enjoy it. A 3.0Ah battery will cut 5–10 branches before depleting. You’ll spend most of your time swapping batteries and waiting for charge. A 4.0Ah or 5.0Ah battery is far more practical, even for light pruning. The weight difference is minimal and the cutting time is worth it.
Are Makita, DeWalt and Milwaukee batteries interchangeable on chainsaws?
No — battery platforms are brand-specific. Makita chainsaws use only 18V LXT batteries. DeWalt chainsaws use 20V MAX batteries. Milwaukee chainsaws use M18 batteries. You cannot mix brands. Each platform has its own ecosystem, but within each platform, all batteries of the same voltage are compatible with all tools of that voltage.
