Next month, Audi will reveal the e-tron quattro concept at the Frankfurt auto show as a preview of the brand’s first all-electric crossover, set to go on sale in 2018.

The easy assumption would be that the latest Audi EV would be based on one of its existing crossover models, but the company says this concept was designed “from the ground up” as an electric, and includes some “creative” aero tricks to create what its maker says is the most aerodynamic crossover on the market (even though this one isn’t on the market yet): there are movable aero elements up front, out back and on the sides, plus an enclosed, flat underbody, all of which Audi says work toward at coefficient of drag (Cd) of just 0.25. For comparison’s sake, the Tesla Model S’ Cd is 0.24, and the recently introduced Audi A4 bests that, at 0.23.

That slippery shape (the body, sized between the brand’s Q5 and Q7, looks more like a lifted, rakish hatchback more than an SUV) allows for a 500-km driving range, says Audi; an EV gets nowhere without a battery, however, and this concept’s lithium-ion cell lives under the floor, between the front and rear axles, positioning that was chosen for its positive effect on the car’s centre of gravity. At this point, it’s worth noting that this apes the basic design of the forthcoming Tesla Model X, which will be a key competitor for the latest electron-driven Audi.

The only other drivetrain detail Audi provides is that there will be three electric motors: one for the front axle, and two for the rear. We’ll be curious to see whether more is revealed in Frankfurt, but we figure Audi will choose to reveal more between now and the car’s 2018 on-sale date.

A futuristic interior includes the same organic LED lighting (OLED) tech as we saw in its Prologue Avant and Allroad concepts, as do the headlights.

The 2015 Frankfurt auto show runs September 17 through 27.

The cabin of the Audi e-tron quattro concept tapers strongly toward the rear end, approaching the idealized shape of an aerodynamically optimized droplet.

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