So far the 2009 Tokyo Motor Show has been surprisingly eventful for hosting so few carmakers. Japan's core of brands has been hard at work releasing new products and concepts. One that almost flew under the radar was Carlos Ghosn's announcement that Infiniti will build a zero-emissions electric vehicle.

A concept version is already being developed, with an eye toward the production vehicle's design goals of a stylish, compact, yet high-performance all-electric four-seater. Nothing else about the new car has yet been released, but it's not outside the realm of possibility that Nissan's LEAF electric vehicle will share some of its technology over to the premium Infiniti brand.

External appearances are likely to be very different, however--despite sharing many platforms between the brands, there are markedly different styling and profile characteristics between Nissan and Infiniti products. Do expect there to be a fair bit of styling influence from the Essence concept, as that model is billed as a sort of distillation of the near future of Infiniti design.

Rumors of a possible Infiniti-branded Audi A3/BMW 1-series-sized EV began to emerge on Monday, so the announcement wasn't entirely a surprise.

Infiniti has also previously announced that it will build a hybrid version of the 2011 M sedan, due in 2012. The newly-announced all-electric compact is expected to make its debut around the same time, though no official dates have been released.