2025 has seen a slew of announcements for high-speed electric vehicle (EV) motors, with several exceeding 30,000 rpm. What is behind this sudden need for speed? A report from IDTechEx discusses the benefits, challenges, and solutions for taking this approach.

In an internal combustion engine (ICE) vehicle, a higher maximum rpm has been associated with higher performance, allowing drivers to ‘rev’their engines out for longer before changing gear. As power is a function of rpm and torque, a higher-rpm engine can deliver higher power at those higher rpms.

In the EV market, the rpm range increased almost immediately. While the average gasoline car would max out at around 5,000-6,000 rpm, the average EV motor is in the 10,000-15,000 rpm range, a speed that can provide the vehicle’s full speed range without the need for multiple gears.

Smaller and cheaper

For the same power output, EV motors are much more compact than a typical ICE, but this hasn’t stopped the EV developers from trying to make their motors smaller and more power-dense to free up space and reduce costs. One route to this is to increase the motor’s top speed.

Tesla and Lucid released the Model S Plaid and Air, respectively, in 2021, both of which have motors with a maximum revolution speed of around 20,000 rpm. In 2025, several announcements of even higher-speed EV motors from players including BYD, Xiaomi, and GAC exceeded 30,000 rpm.

This push to higher rpms has enabled more compact motors with higher power outputs. If the ultimate performance of a motor remains the same but the motor is smaller, the bill of materials is reduced, and the smaller motor allows more space in the vehicle for occupants or other drivetrain components.

IDTechEx’s database found that for radial-flux PM (permanent magnet) machines, increasing the maximum rpm from 10,000 to 20,000 rpm increased power density by 69%, and further increasing to 30,000 rpm yielded another 41% increase.

Problems and their solutions

Pushing motors to higher speeds isn’t without its trade-offs, though. First, there are the AC (alternating current) losses: motors are typically driven through 3-phase current in the stator windings. For a faster motor, the frequency of the sinusoidal current increases, but so do parasitic losses in the stator windings (copper AC losses) and laminations (iron AC losses). Solutions include fewer poles to lower the required frequency and thinner laminations or amorphous materials.

Secondly, at higher speeds, the centrifugal force acting on the rotor increases, making the rotor’s structure a challenge. Solutions: higher speeds can be enabled by a smaller rotor diameter, so centrifugal forces are reduced. Greater effort can also be put into the structural design of the rotor and magnet geometry. Some have also taken to carbon wrapping the rotor to maintain its structure.

Thirdly, a cooling problem might arise: thermal management can be challenging when everything is more compact. Most players are now utilising direct oil cooling to get the coolant as close as possible to the heat-generating components. This is especially crucial for higher-speed motors. While this can add complexity, it may be possible to eliminate the water jacket used in previous designs.

In fourth place come the gear ratios. As the motor spins faster, a higher gear ratio from the transmission is required to achieve the desired wheel speed. Multiple reduction stages can be used, but each would add further cost and complexity. To prevent adding extra reduction stages (beyond the typical 2), the first-stage gear needs to be very small.

Last but not least, there are the bearings. They will experience greater stress, frictional heat, and any imbalances in the rotor translate directly into dynamic forces on the bearings. The solution: greater engineering focus is placed on ceramic (or hybrid ceramic) bearings. They are becoming a standard solution going forward.

Searching for the balance

There are certainly solutions to the challenges of high-speed motors. Still, there has to be a balance between the potential performance and cost benefits of a smaller, higher-speed motor and the possible additional costs and complexity of solutions to the challenges.

With this in mind, a significant portion of the EV market will likely retain motors with a more moderate speed range. Still, there is undoubtedly increased deployment to come for high-speed motors, electric drive units, and eAxles.

IDTechEx’s latest report, Electric Motors for Electric Vehicles 2026-2036, analyses the current technology and materials landscape for electric motors in EVs and forecasts future trends and demand over the next ten years.

The UK-based research company IDTechEx forecasts that over 140 million electric motors will be required for the EV market in 2036 across segments including cars, trucks, buses, 2-wheelers, 3-wheelers, microcars, and light commercial vehicles.