A New Era for EVs: Donut Lab’s Lightweight In-Wheel Motors

• Donut Lab’s second-gen in-wheel motors deliver a jaw-dropping 845 horsepower, cutting down on weight and sporting a futuristic hubless design that could reshape EV innovation.
• By cutting manufacturing costs in half and creating more cabin space, these motors are reshaping EV design.
• While the added unsprung mass might impact performance and comfort, Donut Lab’s technology holds exciting potential for automotive and commercial use.

Donut Lab is reimagining electric motors and the vehicles they drive. electric motors. At CES 2025, they showcased their second-gen-in-wheel drive motors, delivering big power and torque, low weight, and their signature “big hole” design. 

EV design is still rooted in old combustion car layouts, with motors in the body and connected to wheels through a drivetrain. In-wheel motors reimagine this, creating space for cargo and passengers. There is a challenge, though. The motors are huge and heavy, but Donut Lab is ready to take on the challenge.

The second-gen doughnut motor from Donut Lab squeezes into a 21-inch wheel, delivering 630 kW (845 hp) and 4,300 Nm (3,171 lb-ft) of torque per unit. Sounds game-changing, but here’s the catch: without a gearbox to multiply the torque, that figure isn’t as revolutionary as it seems. It’s not a massive leap over something like the Tesla unit.

Donut Lab’s motor takes the spotlight for its lightweight design—a key challenge for EVs. Weighing just 88 pounds (40 kg), it’s about one-third the weight of a standard electric drive unit. This weight savings translates to more range. Even with two motors per axle, eliminating bulky components like half-shafts and CV joints could result in weight savings of hundreds of pounds. Less weight equals more range, and more motors without the weight penalty means better control and power—a double win!

The company claims its motors cost up to 50% less to manufacture, streamlining production by cutting about 120 parts. This could lead to more affordable EVs in the future. Shifting the motor to the wheel arches also opens up chassis space, which could be used for more cargo, extra batteries, a roomier cabin, or bold aerodynamic designs—think Jaguar I-Pace or Polestar 3, but even more extreme.

The big issue here is that while Donut Lab’s wheels are lighter than previous in-wheel motors, they’re still heavier than traditional wheels. To make matters worse, the extra weight is placed in the least ideal location: below the suspension. Adding unsprung mass, as it’s called, affects performance and comfort much more than if the same weight were added to the chassis. Rotating mass is even trickier to manage. With over 80 extra pounds per wheel, it’s bound to impact braking, handling, and ride quality—though just how much remains to be seen.

In addition to the 21-inch automotive wheel, Donut Lab unveiled a semi-truck version designed for efficiency. This version features a lower operating RPM and delivers 200 kW and 2,212 lb-ft (3,000 Nm) per wheel. The company’s expanding lineup will also include a 12-inch scooter motor (15 kW) and a 120mm drone motor (3 kW). Donut’s 150 kW, 17-inch motorcycle motor is already powering a few boutique electric bikes, so seeing this technology in cars in the future is more likely than you might think.