Every Watt counts: How Schaeffler is helping to increase the range of electrified vehicles

Date: Thursday 12 October 2023

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More and more drivers are choosing vehicles with an electrified power train, whether that may be fully electric (BEV), plug-in (PHEV) or hybrid (HEV). However, range anxiety remains the number one issue for those unsure about making the change, with every second driver in Europe listing it as one of their top three concerns they have with electrified vehicles^*.

In Germany, one in five new cars with battery-electric drive was sold in July 2023. However, range of electric vehicles is a commonly cited issue, with every second EV/hybrid driver in Europe reporting it as one of the top three concerns they have with their vehicles. On top of that, the motor isn’t the only thing drawing on the battery. Especially in winter, all those creature comforts also use electricity – at the expense of range. Schaeffler is doing a lot of work in this space, as CEO Automotive Technologies Matthias Zink explains:

“Schaeffler is developing solutions to combat range anxiety. Our smart technical solutions and wide range of components and systems for fully electrified powertrains improve the day-to-day practicality of electric vehicles by reducing power consumption and increasing range.” Drivers thus have to charge their cars less frequently. Depending on the design of the vehicle application, vehicle manufacturers can also use the energy savings to make the battery smaller and thus the vehicle more cost-effective.

“Schaeffler is developing solutions to combat range anxiety. Our smart technical solutions and wide range of components and systems for fully electrified powertrains improve the day-to-day practicality of electric vehicles by reducing power consumption and increasing range.”

High-efficiency bearing solutions
All cars need bearings, and electric cars are no exception. A key way of boosting electric vehicle range is to reduce frictional losses, where energy that would otherwise be used for powering the vehicle is lost as heat through bearing friction. Schaeffler has already developed advanced bearing solutions which are meeting this challenge. A set of highly efficient transmission bearings from Schaeffler can significantly reduce friction, saving about 50 watts of energy compared to conventional solutions- which translates directly into extra range. Alternatively, in Winter, those extra 50 watts can be put towards heating the exterior mirrors or steering wheel, without any loss of range. Just as importantly, Schaeffler’s EV transmission bearings are specially adapted for the high rotational speeds of electric-drive transmission input shafts and are designed to accommodate the optimal load.

To extend range even further, Schaeffler offers TriFinity wheel bearings. Wheel bearings are an integral part of an electric vehicle’s chassis system that guide and support the drive shafts and axles, ensuring that wheels can rotate with minimal resistance, even under high mechanical load. They are subjected to immense forces during normal driving operation and are constantly in motion - rotating around 100 million times for every 70,000 miles travelled.
Schaeffler’s TriFinity wheel bearings reduce frictional losses by a massive 67% compared to conventional bearings, a saving of more than 200 watts, which equates to around 13 miles of additional range in a fully charged electric SUV with a 120-kWh battery capacity. Again, in Wintertime, those extra 200 watts can be used for heating the driver and passenger seats. Seat heating systems consume around 100 watts per seat during the intensive heating phase, whereas the TriFinity wheel bearing actually delivers permanent savings.

The triple-row TriFinity wheel bearing also offers a weight saving of about 10% over standard double-row ball bearings in the same footprint. It also offers a longer service life, and boasts more than 20% greater stiffness, so it can transfer greater axle loads, which is a key advantage, especially in heavier electric vehicles.

Overcoming range anxiety with thermal management
Efficient thermal management offers a major opportunity for range improvement – and it’s an area in which Schaeffler has been developing solutions for around 15 years. Since 2011 Schaeffler has been supplying thermal management solutions to vehicle manufacturers.

“In electric vehicle applications, thermal management has become a decisive influence on many customer-relevant features, such as range and comfort. It is therefore becoming an increasingly key competitive factor for vehicle producers” said Dr. Jochen Schröder, Head of Schaeffler’s E-Mobility division.

Schaeffler is developing a portfolio of high-tech solutions for this, ranging from versatile, multi-application components to highly integrated thermal management systems, and 4-in-1 E-Axles that combine the motor, transmission, power electronics and thermal management in a single, optimised unit. The 4-in-1 E-Axle eliminates the additional hoses and cables required by decentralised thermal management systems, so less energy is lost, and because it has fewer parts, it is both lighter and easier for vehicle manufacturers to install.

This fully integrated solution also yields further increases in range and charging speed because it keeps the powertrain, including the battery, consistently at the right temperature – and also keeps the vehicle’s occupants comfortable. Thanks to the optimised interplay between its four subsystems, the 4-in-1 E-Axle can save about 1 kWh of power per 60 miles of travel in a compact electric car with a 75-kWh battery. That’s approximately seven percent more range, or about 23 miles.

Schaeffler is also developing a new type of heat pump for use both in the 4in1 e-axle and as a stand-alone component. The heat pump turns thermal energy from the surrounding air and waste heat from the motor, power electronics and battery into usable heating. This conserves battery power, which is at a premium in the colder winter months. Compared to a compact car with a 75-kWh battery and decentralised thermal management, the same vehicle with a 4in1 e-axle and heat pump system will use around 4 kWh less energy per 65 miles (measured in WLTC, based on an outside temperature of -7°C). That equates to a 17 percent increase in range, or a gain of 30 miles. Alternatively, that saving can be put into added comfort and safety in the form of heated seats and steering wheel, heated exterior mirrors, and a heated rear windscreen (which together use about 410 watts of power^*). Another advantage of the Schaeffler heat pump system is that it uses the naturally occurring refrigerant carbon dioxide (R744), which is much less harmful to the environment than the conventional refrigerant (Rf1234yf). R744 is non-combustible, has a low greenhouse gas potential, and does not damage the ozone layer. For vehicle producers and owners, this represents an investment in both climate protection and the future.

* Power consumption reference values for vehicle functions (Source: ADAC)

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