Tony O'Kane | Jan 4, 2012

Mercedes-Benz is rumoured to be working on an ultra-lightweight spin-off of its E-Class sedan, reportedly dubbed E Superlight, which will be ready for a production debut in 2015.

Expected to launch in late 2015, the four-door E Superlight will take its styling cues from the F800 and F-125 concept cars, and may feature rear suicide doors and a B-pillarless design.

Carbon-fibre will feature prominently in its construction. Mercedes-Benz is apparently aiming for a kerb weight of just under 1300kg - around 350kg lighter than the current E-Class sedan.

The E Superlight's all-carbon chassis will also give it tremendous rigidity, meaning previously impractical features like pillarless rooflines and gullwing doors may also become a production reality.

A 125kW hydrogen fuel cell and 37kW electric powertrain are expected to be offered in the production E Superlight, however more traditional petrol, diesel and hybrid powertrains may also see service in the featherweight Benz.

Full technical details have yet to be officially announced though, and with the car's proposed launch date so far away don't expect any definitive stats to surface anytime soon.

Mercedes-Benz's aspirations for the E Superlight are reportedly quite modest, with only 20,000 sales targeted for the first full year of production - a fraction of current global E-Class volume.

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