So far, Mercedes' exploration of electric vehicles has been fairly diverse.

It started, logically, with the Smart Fortwo Electric Drive. But then it jumped to the other end of the scale with the SLS AMG Electric Drive supercar.

The next stop could be the Mercedes S-Class luxury sedan, as the company is considering following up a plug-in hybrid variant with a full battery electric version.

According to Top Gear (via Autoblog Green), Mercedes' chief of large cars Dr Uwe Ernstberger says that while an all-electric S-Class isn't an immediate priority, a full battery electric car "will be done in the future".

The car's battery pack is the perennial sticking point--Mercedes is keen to work on finding the right capacity and size to work for S-Class customers.

The priority, he says, is not to sacrifice the S-Class's famed creature comforts and technology simply to carry a battery pack around.

Mercedes has already confirmed an S-Class plug-in hybrid, which Dr Ernstberger says is ideal for occasional trips into the city. The car's electric range is between 15-18 miles, enough to cover brief spells in cities considering zero-emission centers.

The rest of the time, a relatively small (for a luxury sedan) 3-liter V-6 gasoline engine will provide the power--328 horsepower of it--and refinement that Mercedes buyers expect. Importantly, a compact lithium-ion battery pack won't impact upon the car's packaging.

It could be a while before we see an all-electric S-Class though, as even the plug-in hybrid model won't hit U.S. shores until early 2015.

We may be waiting less for a different aspect of S-Class technology though--autonomous driving.

"I think the S-Class is at the very top of the movement of autonomous driving," Ernstberger told Top Gear. The new S-Class already features several autonomous functions--and it's only really legislation stopping Mercedes going further.

What specifications would you like to see from an all-electric S-Class? Leave your thoughts in the comments section below.


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