Bosch Outlines Importance of Silicon Carbide in e-mobility

Bosch says silicon carbide will help overcome range anxiety consumers have about electric vehicles

At a press event in Dresden, Germany, this month, Bosch outlined the importance of silicon carbide (SiC) in its electromobility vision, and how it would help overcome ‘range anxiety’ for electric vehicles.

Bosch said SiC will set the pace in the power electronics in electric and hybrid vehicles. A major benefit of silicon carbide’s characteristics – in terms of switching speed, heat loss and size – is the 50 percent reduction in energy lost in the form of heat. This saving translates into more efficient power electronics and more energy for the electric motor and therefore for the battery range. Bosch emphasized this means motorists can drive six percent further on a single battery charge. Bosch told EE Times Europe it doesn’t believe anyone has quantified the benefit to range and end consumers this specifically previously.

Range anxiety is one of stumbling blocks for potential buyers of electric cars: nearly one in two consumers (42 percent) decide against buying an electric vehicle because they are afraid the battery will run out while they are on the road. In Germany, this anxiety is even more prevalent, affecting 69 percent of consumers. Alternatively, with SiC, car manufacturers can make the battery smaller for a given range. This reduces the cost of an electric car’s most expensive component, which in turn reduces the vehicle’s price. That is because the much lower heat losses of the chips, combined with their ability to operate at much higher operating temperatures, means manufacturers can cut back on the expensive cooling of the powertrain components. That has a positive impact on electric vehicles’ weight and cost.

Jens Fabrowsky at Bosch
Jens Fabrowsky speaking at Bosch’s press event in Dresden (Source: Bosch)

Jens Fabrowsky, a member of the executive management of Bosch’s automotive electronics division, told EE Times that the company has been carrying out R&D on SiC for some time and has a pilot line in Reutlingen, Germany. He added, “We should have some parts in our hands in some time. We’ll start production on 150mm and will eventually go to 200mm.” He wasn’t able to indicate specific timelines. Fabrowsky also highlighted the fact that Bosch is the only company that both makes the automotive system components and the semiconductors.

Bosch’s Harald Kroeger, member of the board of management, said at the press event in Germany, “Thanks to our deep understanding of systems in e-mobility, the benefits of silicon carbide technology flow directly into the development of components and systems.” In addition to power semiconductors, Bosch’s automotive capability includes microelectromechanical systems (MEMS) and application-specific integrated circuits (ASICs).

Kroeger highlighted the increasing semiconductor content in automotive. Whether in airbags, belt tensioners, cruise control systems, rain sensors, or powertrains, there is scarcely a domain in modern automotive technology that does not rely on chips. In 2018, the value of the chips in an average car was around US$370 (€337) (source: ZVEI). While this amount is growing by 1 to 2 percent annually for applications not relating to infotainment, connectivity, automation, and electrification, on average an electric vehicle has additional semiconductors worth $450 (€410) on board. It is thought this figure will increase again by around $1,000 (€910) as a result of automated driving.

This makes the automotive market one of the drivers of growth in the semiconductor sector. With its semiconductor factories in Reutlingen and Dresden, Kroeger said Bosch is well prepared, commenting, “Our semiconductor know-how helps us not only to develop new automotive functions and IoT applications but also to continuously improve the chips themselves.”