A new electric motor known as Ampere, being developed in the UK, is slated to be the world’s most power-dense, delivering 20kW per kg.

A collaboration between Equipmake and HiETA, the Innovate UK-backed project will combine advanced additive manufacturing techniques with thermal efficiency. Its metal structure will be 3D printed instead of milled from a single billet, reducing the quantity of high-strength alloys and magnetic material required, while also minimising weight. The companies are aiming for peak power of 220kW at 30,000rpm and a weight of less than 10kg, which would make Ampere around four times more power-dense than conventional electric motors.
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In a statement, Ian Foley, managing director of Equipmake said: “This exciting project has the potential to totally change our concept of what an electric motor can offer, and with such a huge amount of performance in a such a small package at as low a cost as possible, this motor is set to further revolutionise e-mobility, whether that’s in automotive or aerospace. We are grateful to Innovate UK for their support and are looking forward to getting the very first Ampere prototypes up and running very soon.”
Key to the performance of Ampere will be the motor’s thin walls and complex internal geometries, created by HiETA using selective laser melting (SLM). The technique allows components to be built using very fine layers of metal powder, which – unlike selective laser sintering (SLS) – are fully melted into single components rather than simply fused together.
“Ampere provides the opportunity to apply both HiETA’s thermal management expertise and complex, thin-walled structure manufacture enabled by additive manufacture to electric motor design to realise ambitious power densities,” said Andy Jones, innovation programme manager at HiETA.
“We typically reduce the size of thermal management components by five times compared with conventional techniques which will allow next-generation heat transfer features to be integrated into the rotor, stator and electronics cooling. In addition, the freedoms of additive manufacture will be used to optimise structural performance.”
People really need to stop calling products after SI units.
Was “Ampere” really the best name the marketing department could come up with?
This motor claims to achieve 2.6x the mechanical power output per unit mass when compared to another highly developed 200kW @ 17500rpm, 26kg electric motor designed in 2013 at McLaren Applied Technologies for EV motorsport! However , a lot of this new motor’s impressive gain in maximum specific power is achieved by spinning its rotor 71% faster than that of the Mclaren (power being proportional to rotor speed of course), hence wonder if the additive manufacturing process has better sound-proofing properties compared to the traditional method of stamped laminations?
Does that power to weight ratio include the weight of the gearbox needed to convert 30,000 rpm into something a bit more useable?
Steve, exactly. Torque density is more useful in real applications.