GKN’s eAxle migrates to C-segment cars

GKN is attempting to increase its return on investment in hybrid technology by pushing its technology to a wider C-segment OEM audience.

GKN Driveline has simplified, and therefore cut costs of its eAxle technology (at present used by the Porsche 918 Spyder and BMW i8) to make it more attractive for use in what it calls ”affordable compact vehicles”.

It presumably has an eye on more BMW products, as well as those from VW (Audi), Mercedes-Benz and maybe even Ford Motor Company

The company has developed an eAxle module that will enable C-segment vehicles to offer buyers a plug-in hybrid option with improved performance and a reduction in CO₂ emissions of more than 50 per cent.

The new eAxle, a development of the system GKN designed for the Porsche 918 Spyder, is a single-speed design that cuts the weight to 20.9kg while attempting to optimise efficiency, installation space and cost for mass-market vehicle applications.

A two-staged gear-train with a gear ratio of 12.5 provides up to 2000Nm torque and 65kW power for a dynamic pure-electric mode and balanced wheel torques for all-wheel drive mode.

An electromechanically-actuated dog clutch disconnects the electric motor at higher vehicle speeds and an open coupling minimises rotating losses when disengaged.

Such transmission devices require precision engineered gear teeth as well as other acoustic measures to ensure minimal noise emissions and smooth action.

GKN claims its development is helping move the balance of power in vehicles from internal combustion towards electric drives.

A typical C-segment plug-in hybrid could now have an engine output of around 100kW, with an eAxle supplying an additional 65kW of electrical power. The eAxle can improve 0-60 mile/h acceleration times by several seconds, provide a useable pure electric range and reduce a vehicle’s CO₂ emission rating to less than 50g/km.

Engineers can integrate single-speed eAxle modules into the rear assembly of front-wheel drive vehicle platforms to provide a combination of plug-in hybrid and electric all-wheel drive functionalities.

GKN Automotive president of engineering, Peter Moelgg, claims GKN leads the industry in eAxle technology.

“We want to make plug-in hybrids a simple upgrade for consumers and manufacturers,” he declared with an eye on broadening the appeal of the technology.

“With our systems now proven in halo hybrid sports car programmes and premium SUVs, automakers are working with us to launch eAxle technology in a much broader range of vehicles,” he said.

“Innovations by our hardware and software engineers will place the performance and efficiency benefits of plug-ins within the reach of many more motorists,” he added.

Rainer Link, GKN Driveline managing director of eDrive Systems, added his viewpoint to those of his boss: “GKN’s position as the only hybrid technology supplier that can also deliver complete all-wheel drive systems makes us an ideal partner on these programmes. Our vehicle integration teams can support automakers in the tuning of their vehicle’s eAWD mode, ensuring that the torque delivery results in the right front-rear balance and delivers the brand’s trademark driving characteristics.”

GKN claims it has been pioneering the introduction of eAxle technology since 2002. It launched the industry’s first high-voltage eAxle applications with PSA Peugeot Citroen in 2010.

The company was awarded Official Porsche Technology Partner status for its contribution to the plug-in hybrid Porsche 918 Spyder programme. GKN followed this with the world’s first two-speed eAxle in the plug-in hybrid BMW i8. It supplies also the eAxle on the Volvo XC90 T8 Twin Engine PHEV programme.