Donut Motors and the Elaphe in the Room at CES 2025
Damn the unsprung weight and full speed ahead on wheel-mounted e-motors!
Momentum is building to clear the skateboard chassis of electric motors, freeing up valuable packaging space for people and cargo while taking advantage of finer control of traction for braking and stability controls. Lightyear and Lordstown Motors each had grand plans to produce vehicles with in-wheel motors before each went bankrupt, but their problems weren’t attributable to the location of their motors. Three big players in this burgeoning field displayed their wares at CES 2025, each making newsy claims.
Donut Lab
“Highest torque and power density in the world, by far.” That’s the bold claim made by Donut Lab, a subsidiary of Finland’s Verge Motorcycles. And while it’s available in hub-less (open center) wheel form on the $30,000 boutique Verge TS bike, at CES 2025 the company introduced a family of five related motors capable of powering cars, semis, motorcycles, scooters, and aerial drones. The headline-grabbing 21-inch hypercar version makes 845 hp and 3,172 lb-ft of torque per motor in a package that weighs just 88 pounds. Another 21-inch version optimized for longevity in semi-tractor duty makes 268 hp and 2,213 lb-ft. Two-wheeler options include a 17-inch, 46-pound one for motorcycles that makes 201 hp and 885 lb-ft, and a 12-inch 18-pound one for scooters good for 20 hp and 221 lb-ft. Last is the 4.7-inch-diameter 3.3-pounder that makes 4 hp and 15 lb-ft.
Donut Lab touts its design’s simplicity, ease of construction, and light weight as advantages, citing a study converting a compact SUV (think Model Y) to Donut Lab wheel-motors. It claims its system enables a $2,000 overall bill-of-materials cost savings, 6 cubic feet of space savings onboard, 187 pounds of overall mass savings, plus an 8-hour reduction in assembly time.
Exact specifics of the motor’s workings are still in short supply, but photos indicate sort of an inside-out radial-flux design that rings the stator with individual coil windings arrayed like pistons in a radial engine. These act on permanent magnets that, at least in the motorcycle’s case, are built into a carbon-fiber wheel. This placement maximizes the leverage these magnets can exert.
Photos and models available to date afford no clues as to how a mechanical brake is arranged (bicycle-style pads grabbing the rim are not in evidence). Watch this space as time goes by for more info on what exactly makes these intriguing motors tick, but we’re hopeful that in the next installment of the 007 franchise, Q Branch will deploy a Latvian Oruga single-track snow bike powered by the Donut Lab motor.
DeepDrive
DeepDrive’s claim to fame is that its single stator energizes two rotors, which has helped attract investment from BMW and Continental. At the Continental booth at CES 2025 we got to see a cutaway of the motor to get a better idea of how it works—though the company is so cagey about its IP that the cutaway was missing the stator winding, and the rotors were devoid of magnets. (C’mon, patent that thing already and show us how it works!)
What we can show (and tell) you is that the stator is mounted to a cylindrical ring that is then mounted to what looks like a drum brake backing plate, and that the rotor magnets mount to what looks like a pair of concentric cylinders that form the brake drum. And because it’s all so drum-like, the demo included an actual drum brake inside, with shoes expanding against a completely separate steel piece, not the rotors. It serves both service and parking brake functions.
We’re told the linings are expected to last the lifetime of the car (because strong regen means they’ll seldom get use), and that they can be electrically or hydraulically actuated. This novel design is said to greatly reduce eddy currents. That means that for an equivalent power/torque output, the DeepDrive motor requires less permanent-magnet material and less cooling than conventional motors.
Motors are in the works to fit within 16- and 19-inch rims. Varying the width of the stator/rotors can further fine tune the power to suit different applications. Continental reps forecast the first DeepDrive applications hitting the road in 2028.
Elaphe Sonic.1
One of Slovenian Elaphe’s big selling points is that its ring-shaped motors fit inside a wheel leaving enough space for a typical, large brake and caliper fitment suitable to very high-performance vehicles. The gullwinged ItalDesign Quintessenza, first displayed in China, has since been fitted with two 400 hp/1,843-lb-ft front and two 671-hp/4,425-lb-ft rear Elaphe wheel motors. And indeed, they each have a big 15.7-inch disc and multi-piston caliper visible, to suggest hypercar track capability.
Elaphe also touts the extreme precision control its motors allow—high-bandwidth sensing of torque, position, and speed at 10 kHz and millisecond torque response greater than 350 lb-ft/millisecond. These capabilities allow Elaphe motors to reduce time to launch and accelerate by 10 percent relative to equivalent power from other motors, to shorten stopping distances by up to 15 percent, and to improve lateral acceleration by 15 percent via torque vectoring. Elaphe even claims its motors themselves generate engine-like vibroacoustics—both sound and vibration—that add emotion to the visceral acceleration. Production of some sort is claimed to be coming in the third quarter of 2025.
I started critiquing cars at age 5 by bumming rides home from church in other parishioners’ new cars. At 16 I started running parts for an Oldsmobile dealership and got hooked on the car biz. Engineering seemed the best way to make a living in it, so with two mechanical engineering degrees I joined Chrysler to work on the Neon, LH cars, and 2nd-gen minivans. Then a friend mentioned an opening for a technical editor at another car magazine, and I did the car-biz equivalent of running off to join the circus. I loved that job too until the phone rang again with what turned out to be an even better opportunity with Motor Trend. It’s nearly impossible to imagine an even better job, but I still answer the phone…
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