6 Best Extended Run Batteries For Cordless Chainsaws That Finish the Job
Maximize your cordless chainsaw’s potential. Our guide reviews the 6 best extended run batteries for longer run-time and the power to finish any job.
There’s nothing more frustrating than being halfway through clearing a downed oak on the back fenceline, only to have your chainsaw battery die. You’re a long walk from the barn, daylight is fading, and the job is only half done. The right battery isn’t a luxury; it’s the difference between a productive afternoon and a wasted one.
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Why Battery Amp Hours Matter for Farm Chores
Amp hours (Ah) are the fuel tank for your cordless chainsaw. A higher Ah number, like 9.0Ah, simply means the battery can deliver its power for a longer period than a smaller one, like a 2.0Ah. Think of it this way: voltage is the horsepower of the engine, but amp hours are the size of the gas tank.
For farm chores, this is everything. You’re not just making a few quick cuts next to the garage; you’re often working far from a power source for an extended time. Clearing brush, bucking up a winter’s worth of firewood, or limbing trees along a pasture requires sustained cutting. A small battery might get you 15-20 minutes of work, while a large extended-run battery can push you for an hour or more, letting you finish the task in one go.
Don’t get bogged down in the math. Just know that when a battery is advertised as "extended run," it’s because of its high amp-hour rating. For the kind of work we do, anything under 4.0Ah is best left for light trimming. For serious work, you need to be looking at 6.0Ah and up to avoid constant trips back to the charger.
DeWalt FLEXVOLT 9.0Ah: Maximum Power Output
The DeWalt FLEXVOLT system is built around a clever idea: the battery automatically changes its voltage to match the tool. When you snap this 9.0Ah battery into a 20V DeWalt tool, it delivers 9.0 amp-hours of runtime. But put it on a 60V FLEXVOLT chainsaw, and it reconfigures itself to deliver 3.0Ah at a much higher voltage, giving you incredible cutting power.
This makes it a beast for tough jobs. That high-voltage output translates directly to chain speed and torque, letting you power through dense hardwood without the saw bogging down. It’s the battery you grab when you need to fell a medium-sized tree or buck up thick, stubborn rounds for the wood splitter.
The main tradeoff here is weight. This is a substantial battery, and you’ll feel it after an hour of work. But if your primary concern is raw power to get through the most demanding cuts, the FLEXVOLT 9.0Ah is hard to beat. It turns a cordless saw into a true gas replacement for many farm tasks.
EGO 56V 7.5Ah ARC Lithium for Longest Runtime
EGO built its reputation on battery technology, and this 7.5Ah pack is the reason why. Its unique "ARC Lithium" design helps dissipate heat, which is the number one killer of battery life and performance. This means it not only runs longer but maintains its power throughout the charge cycle without fading.
This battery is the marathon runner of the group. The combination of high voltage (56V) and massive capacity (7.5Ah) delivers the longest, most consistent runtime you’ll find. It’s perfect for those all-afternoon jobs, like clearing an entire overgrown fenceline or processing a large brush pile. You can often work until you need a break, not because the battery does.
While EGO tools are excellent, you are buying into a dedicated outdoor power equipment system. Unlike DeWalt or Milwaukee, you won’t be running your impact driver with this battery. But if your goal is maximum, uninterrupted cutting time for property maintenance, this battery lets you work from start to finish without thinking about the charger.
Milwaukee M18 HD12.0: Pro-Grade Endurance
Milwaukee’s M18 High Output 12.0Ah battery is the definition of professional-grade endurance. It was designed for the most demanding job site tools, and that toughness translates perfectly to the farm. This battery is built to be dropped, rained on, and pushed to its thermal limits all day long.
The sheer capacity of 12.0 amp-hours is staggering. On an M18 Fuel chainsaw, this translates into an incredible number of cuts per charge. This is the battery for someone who plans to spend the entire day cutting firewood, effectively replacing a tank of gas. Its advanced electronics communicate with the tool to prevent overload, ensuring you get maximum power without damaging the equipment.
Like the DeWalt, this is a heavy battery. It’s best paired with Milwaukee’s larger M18 Fuel 16" chainsaw, where its weight is better balanced. For a smaller limbing saw, it would be overkill. If you’re already invested in the M18 system and need a battery that simply will not quit, the HD12.0 is the top of the mountain.
Makita 18V LXT 6.0Ah: Best for System Users
Makita takes a different approach. Instead of a single, massive high-voltage battery, their more powerful chainsaws use two 18V LXT batteries together to create a 36V system. The 6.0Ah battery is the sweet spot for this setup, offering a fantastic balance of runtime and weight.
The genius of this system is its versatility. You have two 6.0Ah batteries that can power your chainsaw with serious performance, but you can also pop a single one into your drill, impact driver, or circular saw. For anyone already running Makita tools, this is a huge advantage. It means fewer types of batteries and chargers to keep track of in the workshop.
Using two batteries provides a combined 6.0Ah at 36V, which is plenty of juice for most farm-scale jobs, from post-storm cleanup to preparing firewood. It may not have the absolute longest runtime of an EGO or the sheer grunt of a FLEXVOLT, but for a user deep in the Makita ecosystem, it’s the most practical and efficient choice.
Ryobi 40V 6.0Ah: Top Value for Large Yards
Ryobi has mastered the balance between performance and price, and their 40V 6.0Ah battery is a prime example. It delivers solid runtime and sufficient power for the vast majority of tasks a hobby farmer will encounter, but at a fraction of the cost of the pro-grade brands. This is the workhorse battery for the budget-conscious.
This battery provides a significant upgrade over the smaller 2.0Ah or 4.0Ah batteries that often come with the tool. It gives you the confidence to tackle larger projects, like clearing a few saplings or cutting up a winter’s supply of kindling, without worrying about running out of power halfway through. It’s more than capable for seasonal pruning and cleaning up fallen limbs.
Is it built to withstand the daily abuse of a professional crew? No. But it doesn’t need to be. For weekend work and seasonal property maintenance, the Ryobi 40V 6.0Ah battery provides the best overall value, giving you the extended runtime you need to get the job done without breaking the bank.
Greenworks Pro 80V 4.0Ah: High-Voltage Power
The Greenworks 80V system demonstrates a different side of the power equation. By using a very high voltage, they can achieve incredible cutting performance with a battery that has a lower amp-hour rating, like this 4.0Ah pack. The high voltage delivers power to the motor with extreme efficiency, resulting in chain speeds that rival gas saws.
This battery feels surprisingly light for the power it puts out. It’s an excellent choice for tasks that require both power and maneuverability, like limbing trees from a ladder or clearing thick, tangled brush where you’re constantly changing your cutting angle. The system also benefits from very fast charge times, so even if you do run it down, you’re not waiting for hours to get back to work.
The tradeoff is that a 4.0Ah battery, even at 80V, won’t have the same epic runtime as a 7.5Ah or 12.0Ah pack. You’re trading some longevity for explosive power and a lighter-weight tool. It’s a fantastic option for intense, shorter-duration jobs where cutting speed is the top priority.
Matching Battery and Chainsaw for Best Results
The biggest battery isn’t always the best choice. The key is to match the battery to both the tool and the task at hand. Putting a massive, 8-pound Milwaukee HD12.0 on a small 12-inch top-handle saw would be a disaster. The balance would be terrible, and the fatigue would be immense.
Think about the job.
- Light Limbing and Pruning: A smaller, lighter 4.0Ah or 5.0Ah battery is perfect. You’ll appreciate the reduced weight when reaching overhead.
- General Firewood and Fenceline Clearing: This is the sweet spot for the 6.0Ah to 9.0Ah batteries. They provide the ideal blend of runtime and power without excessive weight.
- All-Day Bucking and Felling: When you’re processing a whole tree or cutting for hours, the biggest batteries like the EGO 7.5Ah or Milwaukee 12.0Ah are your best friends. The extra weight is a worthy trade for not having to stop.
Ultimately, the goal is to create a balanced tool that has enough power and runtime to finish the job you’ve started. Don’t just buy the battery with the biggest number on it. Consider how it will feel after an hour of work and whether the runtime it provides truly matches the scale of your projects.
Choosing the right extended-run battery transforms your cordless chainsaw from a convenient trimming tool into a serious piece of farm equipment. It’s about investing in uninterrupted workflow and the confidence that you can finish what you start, no matter how far you are from the nearest outlet. That kind of reliability is what makes modern battery power a true game-changer for the small farm.
