In an interview with Autocar, company insiders divulged that the platform underpinning the innovative BMW i3 platform could be stretched to create a family car spinoff.

BMW engineers want to add just 100 mm of extra legroom and 150 mm of rear overhang to the four-metre i3 to create a spacious family EV that won't be much longer than a Mini Countryman. The firm has already trademarked the monikers i1 through to i8, so it's possible that the new model could wear the i5 badge.

Lengthening the i3 would be a matter of extending the chassis's longitudinal aluminium extrusions. This is a much cheaper and simpler operation than stretching a conventional steel monocoque. With the body being made out of carbon fibre-reinforced plastics, the pillarless passenger cell can be stretched by extending the roof and floor sections, only the rear door structure would have to be completely re-engineered.

Should the i5 be given the green light, it could be on the cards for a mid-2015 reveal.