Mercedes S500 PHEV

Putting a bank of batteries into the Mercedes-Benz S-Class is not a new idea – the S500 Vision Plug-in Hybrid concept was unveiled in Frankfurt in 2009, after all – but actually adding a cord to a production version sure is – at least in public. We don't know how long Daimler has been considering making a plug-in hybrid version of the S-Class, but Australian media outlets are reporting that such a vehicle was accidentally disclosed during a recent presentation in Germany.

Motoring and Car Advice both say they saw a graphic of a "W222 S-Class PHEV" that showed a dash indicator of remaining battery range. There was also a "graphic drivetrain schematic featuring an electric motor sitting behind a conventional engine and a battery pack positioned in the boot," writes Car Advice. Despite this, there is, of course, no guarantee that any such vehicle will ever make it to market. And, as we asked years ago when we reviewed the 2010 Mercedes-Benz S400 Hybrid, who is it for?

A M-B spokesman in Australia, Jerry Stamoulis, told Motoring that, "The reality is that there is a lot of spec still to be confirmed; the car is so far away for us. It's (the mainstream S-Class is due here) in December – and if there were plug-in hybrid variants there's no guarantee that they're actually available from launch anywhere in the world." It'll take a while to see if showing off the image was a mistake or a leak to gauge interest, but we admit we like this tease.