The electric axle drive system combines three powertrain components into one unit. Source: BoschThe electric axle drive system combines three powertrain components into one unit. Source: Bosch

A new generation electric axle drive, or e-axle, developed by Bosch combines three powertrain components into one unit. The motor, power electronics and transmission form one compact unit that directly drives the car’s axle. The e-axle can be installed in hybrids and electric cars, compact cars, SUVs and even light trucks.

As Bosch customizes the powertrain to each automaker’s requirements, customers no longer have the time-consuming task of developing new components. Bosch already has a flexible, globally applicable manufacturing concept for this component. The concept guarantees that each customer will get a customized solution that can be quickly integrated into its manufacturing operations.

The powertrain can deliver between 50 and 300 kW, and is therefore also capable of powering large vehicles such as SUVs completely electrically. Torque at the vehicle axle can range from 1,000 to 6,000 Newton meters. When installed in hybrid and electric vehicles, front- and rear-axle drive is possible.

An electric axle delivering 150 kilowatts weighs roughly 90 kilograms, and thus far less than the combined individual components used. By combining power electronics, electric motor and transmission in a single component, fewer parts are needed. For example, the new electric powertrain does completely without thick and expensive copper cables linking the components. In addition, the cooling system can be simplified, and there is no need for bearings for rotating components. This reduces the powertrain’s cost while increasing its efficiency. Placing the transmission close to the motor saves valuable installation space, which is always an important factor in the auto industry.

Samples of the electric axle are ready for use, and are currently being tested. Start of production is planned for 2019 at the latest.

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