Industry cooperation for more efficient electric cars

Science is often criticized for conducting abstract basic research. The way neutron research improves motors for electric cars is demonstrated by a project that will start in spring 2024 between researchers from FRM II, TUM, and RWTH Aachen University in collaboration with automotive supplier Mubea.

The points between the magnets are the embossings in the material of the rotor. They partially block the magnetic fields so that they are optimally conducted, thereby increasing the efficiency of the electric motor. © Reiner Müller, FRM II/TUM

The points between the magnets are the embossings in the material of the rotor. They partially block the magnetic fields so that they are optimally conducted, thereby increasing the efficiency of the electric motor. © Reiner Müller, FRM II/TUM

Although electric cars are already significantly more efficient than modern combustion-powered cars, any improvement in efficiency, however small, can save significant amounts of energy.

Optimal magnetic field in the motor
To increase the efficiency of electric motors, their magnetic fields must be optimized. In a six-year collaboration, researchers from FRM II, the Chair of Metal Forming and Casting Technology at TUM and the Institute of Electrical Machines at RWTH Aachen University have developed a new method for this: they emboss the material and thus selectively block the magnetic fields without impairing the mechanical stability of the highly stressed components. This allows the motors to rotate faster and work more efficiently.

PhD student Simon Sebold at the grating interferometer of the ANTARES instrument. © Bernhard Ludewig, FRM II / TUM

PhD student Simon Sebold at the grating interferometer of the ANTARES instrument. © Bernhard Ludewig, FRM II / TUM

Neutrons see magnetic fields inside
‘Conventional methods only record the magnetic fields on the material’s surface. However, this is not very informative for the processes inside,’ explains Dr Michael Schulz, Head of the Imaging Methods Group at the FRM II and MLZ and scientist at the ANTARES neutron radiography and tomography facility. ‘With our neutron grating interferometer, we can see exactly how the local magnetic fields inside the material behave.’

Funded by the DFG
German automotive supplier Mubea will collaborate with researchers from the ANTARES group at FRM II and MLZ for two years from spring 2024 to determine the most efficient embossing strategy for electric motor components. The Deutsche Forschungsgemeinschaft is funding the project at FRM II with over €136,000.

Simple idea leads to exciting development
Michael Schulz adds: ‘We are very pleased that in this project we have come together from the basic idea of embossing to a direct application for an industrial partner.’ The researchers now look forward to new impetus to align their work with industry requirements.