Brushless motors already replaced brushed designs in most cordless tools, and the next step is a change inside the stator. A segmented brushless motor winds the stator coils in separate sections that are joined after winding, which packs more copper into the same space. Manufacturers describe the result as the most power-dense motor they have produced: more power, higher efficiency, smaller size, and less weight in one package. Understanding brushless motor tiers, from standard brushless to Fuel-class designs, puts the segmented stator in context before you compare tools.
The first tools with segmented motors are high-powered cordless circular saws, and the same technology is expected in more tools where power density is a top priority. This article explains the stator design, the electronics changes, and what the shift means for runtime and tool choice.
How a Brushless Motor Works, From the Stator Out
A brushless motor replaces the mechanical commutator and brushes of older designs with an electronic controller that switches current through the stator coils. The rotor turns because the magnetic field rotates around it. The stator is the ring of coils, and its geometry sets the ceiling for power and efficiency. The payoff shows up most clearly in compact cordless power tools, where the motor has to fit a small housing without giving up output.
The comparison between a standard brushless motor and a segmented unit is visible at a glance: the segmented stator has fewer gaps between coils, and the winding pattern looks denser. Inside the tool, the difference shows up as higher peak output and a motor that holds speed under load.
From Conventional to Segmented Windings
In a conventional stator, coils are wound around a one-piece core, which leaves air gaps between coil groups. A segmented stator is wound in separate pieces and then welded together, which removes most of those gaps. The freed space is filled with more copper windings, and more copper means more power for the same motor size.
Why Fewer Air Gaps Means More Power
Air gaps are wasted volume: they add size without adding torque. Copper carries the current that creates the magnetic field, so packing more copper into the stator raises output. The trade-off is manufacturing cost, because each segment is wound and joined separately, which is why the design will not appear in every tool.
Power Density and Efficiency in Real Terms
Power density is the output per unit of motor size, and it is the number that matters when a tool has to fit a saw body or a drill housing. The segmented motor delivers more torque per cubic inch, which lets manufacturers keep the tool size down while pushing performance up. Efficiency is the second half of the story: a motor that wastes less energy as heat leaves more battery capacity for actual work, which extends runtime between charges.
The practical test is simple: run the same cut with an older motor and a segmented motor on the same battery. The segmented tool finishes faster, and the battery indicator stays higher when the cut is done. Those two measurements, time and remaining charge, capture both halves of the improvement.
Reading Efficiency Curves
Brushless motors are most efficient in a middle band of the speed and torque range. The electronic controller keeps the motor in that band by adjusting current, which is why a well-matched motor and controller outperform a bigger motor with sloppy control.
The Ergonomics Side of a Lighter Motor
Weight savings change how a tool feels over a full shift. A lighter saw reduces arm fatigue, and the same design thinking shows up across the gear a worker carries; technical workwear such as the FreeFlex tech pants reviewed by Pro Tool Reviews is built around the same goal of reducing fatigue and improving comfort.
Electronics That Keep Up With the Motor
A powerful motor is only as good as the electronics that feed it. The segmented motor launch pairs the stator with a redesigned controller and thicker power wiring, roughly 8-gauge superflex wire, which lowers resistance between the battery and the motor. High current draw needs low-resistance paths, and this part of the design is what transformed cordless power tool performance in the last generation of tools.
Thicker Wire, Less Resistance
Every connection in the power path drops voltage under load. Thicker wire cuts that drop, so the motor sees higher voltage exactly when it needs it, at the start of a cut. The superflex insulation keeps the heavier wire manageable inside the tool housing.
Thermal Management
Copper losses and switching losses generate heat, and heat degrades both motor and battery. The redesigned package shrinks the electronics and improves airflow, which lets the tool sustain power longer before thermal limiting kicks in.
Where High Power Density Matters Most
The tools that benefit most are the ones that stall first with older motors. Drills and drivers stall when the bit binds, and saws stall when the blade loads up in dense material. A power-dense motor holds speed through the stall point, which is why cordless drill technology keeps improving construction productivity; operators spend less time feathering the trigger and more time cutting.
The manufacturer confirmed that segmented motors will ship in more tools where high power in a smaller size is the top priority, without naming specific models. For planning purposes, expect the technology in tools that currently struggle to match their corded equivalents.
Drills and Drivers
In a drill, extra headroom means the chuck keeps turning through a knot in lumber or a seized screw. In an impact driver, the motor feeds the hammer mechanism faster, which shortens drive times on long fasteners.
Saws and Grinders
Circular saws are the current flagship for the segmented design because they need sustained power, not just bursts. Grinders sit in the same category: they draw current continuously, so motor efficiency translates directly into runtime.
| Tool class | What power density delivers | User-visible result |
|---|---|---|
| Circular saws | Sustained speed through dense stock | Fewer stalls and straighter cuts |
| Drills and drivers | Headroom at the stall point | Faster fastening, less trigger feathering |
| Grinders | Continuous high current delivery | Longer runtime between charges |
| Compact tools | Full output in a smaller body | Less fatigue and better access |
Battery Pairing and Platform Considerations
The segmented motor was designed to match the most powerful battery in the 18V family, a 12Ah high-output pack with FORGE cell technology. Motor and battery are tuned as a system: the motor draws what the battery can deliver, and the battery is built to hold voltage under that draw. For buyers, the practical question is whether existing packs can feed a segmented-motor tool, and the answer shows up in the recommended battery on the spec sheet. The same logic already plays out in cordless circular saws for construction work, where saw and battery are sold and rated together.
Battery technology moved in parallel. The 12Ah FORGE pack uses a cell format that improves cooling and lowers resistance, so it can sustain the current a segmented motor draws. Older packs may still run the tool, but the performance gap will show in cut speed and runtime.
Matching Motor to Battery
Pairing a power-hungry motor with a weak battery wastes both: the motor cannot reach full output, and the battery overheats. Manufacturers rate tools with a recommended minimum pack, and staying above that line protects runtime and battery life.
Runtime Trade-Offs
High-output batteries weigh more and cost more. A 12Ah pack extends runtime but changes the balance of a tool in your hand. Crews often run a mix: high-output packs for cutting tools and lighter packs for drills and drivers.
Planning Tool Purchases Around New Motor Technology
Segmented motors will not appear in every tool, because the manufacturing cost is higher than conventional brushless stators. They will show up where power density is the priority: saws, grinders, and future high-drain tools. Buyers who track how brushless motor technology in cordless power tools for construction keeps moving can time purchases around generational upgrades instead of buying a tool that is one step behind.
Buying Checks for the Next Generation
- Confirm the recommended battery for the tool and whether you already own it.
- Compare power ratings against the previous generation, not the marketing.
- Check that accessories stay compatible with the new motor package.
- Price the tool against the total platform cost, including battery upgrades.
Motor technology moves in steps. Segmented stators are the latest step, and they arrive first in the tools that strain the old design the most. When your current saw or grinder stalls on the job, that is the moment to look at what the new motors actually deliver.