The “gold” of the electric-car future

Automotive-sector | The work thyssenkrupp is carrying out at a research center in the northeast of Bochum is set to change the game for the electric car segment: On the site of the historic steel mills, once famed for the manufacture of wire rope and casting of church bells, the company today produces a component that is vital to the working of an electric motor – electrical steel. As a leading manufacturer of this “gold” for the new era of transportation, thyssenkrupp is working to continuously extend the operating range of electric vehicles.

Looking round the huge E-Mobility Center Drives buildings at Castroper Strasse 228, the first thing that strikes you are the shimmering matte-finish coils of a very special, very thin (as low as 0.18 millimeter) material known as electrical steel. At first glance the job of this high-tech product is pretty unspectacular: “It improves the performance and efficiency of electric motors – from household mixers to wind turbines,” says Marco Tietz, head of applications development for the material at the site. But for him the heavy coils of electrical steel surrounding him are anything but unspectacular, they are no less than the Holy Grail of e-mobility. As significant for the future of motoring as the Apple I was for the breakthrough of the personal computer.

E-mobility tests electrical steel to the limit

But what makes electrical steel so valuable for the future of the electric car? The answer can be found deep inside the motor of an electric vehicle. The electrical steel used in the stators and rotors has a crucial influence on the efficiency of the motor: The better it minimizes core losses, the greater the efficiency of the motor – and thus the range of the vehicle. While the motors in industrial machinery operate at speeds of only 5,000 to 8,000 revolutions per minute, many of today’s powerful electric motors reach speeds four times as high. The heat this creates drastically increases the potential core losses. In addition, due to the higher speeds the electrical steel has to withstand higher mechanical loads. No wonder, then, that researchers the world over are working on improved electrical steels.

Setting new standards for electric motors

In 2015 thyssenkrupp developed an electrical steel that is particularly well suited to meeting the requirements of electric vehicles: Core losses have already been reduced to almost 30 percent below the levels of conventional grades, while the steel’s enormous strength allows high-speed motors to be installed in very small spaces. That’s a game changer for customers too: Numerous OEMs are currently testing the new product in their prototypes.

Taking it further

The experts at thyssenkrupp are already researching into new, even more efficient generations of electrical steel. Marco Tietz is among those whose days are spent working on electric motors that consume less power, are lighter, longer-lasting and more affordable, so as to extend the operating range of electric vehicles. At E-Mobility Center Drives in Bochum he has ideal conditions for his work. “To make this material you have to meet the highest standards. This is where thyssenkrupp has a distinct advantage: Our metallurgy is so good that, together with our colleagues, we’re able to develop and test new approaches quickly and easily.” So the continued development of this key player in the evolution of the electric car is in good hands at thyssenkrupp.