Prospects for R8 E-tron Darken, as Audi Shifts Focus to Plug-in Hybrids The Audi R8 E-tron, a purely electric version of Audi's sinuous, midengine flagship GT, was scheduled to go on sale at the end of the year. The car's march toward the dealership, however, appears anything but assured. According to a report by Car and Driver this week, spiraling battery costs and limited driving range were conspiring to delay the R8 E-tron, or stop the program entirely. But Brad Stertz, corporate communications manager for Audi of America, said the program had in fact not been derailed, though the R8 E-tron remained more of a road-based laboratory than a prototype about to enter production. "All along, Ingolstadt has been saying there would be a limited production run at first," Mr. Stertz said in a telephone interview on Thursday, referring to the corporate base of Audi AG. In a follow-up e-mail, he wrote, "The plan for the R8 E-tron is for the production of 10 in an initial series run, which will continue to serve as a technology platform." Those 10 vehicles would be "strictly for internal use," he said. Though he would not commit to a timetable, Mr. Stertz said Audi would eventually "consider the circumstances surrounding the feasibility of subsequent builds." He declined to address explicitly the prospects of the R8 E-tron's making its date with dealers by the end of this year. The R8 E-tron has been several years in the making for Audi, which unveiled the car in concept form during the 2009 Frankfurt motor show. The automaker recently ran an R8 E-tron prototype at the 12.9-mile Nürburgring racetrack in Germany, where it set what Audi claimed was a lap record for an electric-powered, production-intent vehicle, with a time of 8 minutes 9 seconds. The prototype that ran the Nürburgring, which was mechanically identical to the eventual production car, Audi said, was equipped with a lithium-ion battery pack with 49 kilowatt-hours of capacity. The rear-drive coupe accelerates from zero to 62 miles per hour in 4.6 seconds, Audi claims. Range for the prototype is estimated at 134 miles, slightly better than many E.V.'s, although relatively high energy capacity helps in that regard; a Nissan Leaf makes do with roughly half the battery capacity. The range is also slightly lower than that of the Mercedes-Benz SLS AMG Electric Drive prototype, estimated by Mercedes at 155 miles. That car, unveiled at the Paris motor show last month, is listed at 416,500 euros in Germany, roughly $540,000, a premium of more than $300,000 over the standard gasoline-powered model sold in America. The introduction of another R8-based E.V. project, the F12, is intended to run "in parallel" with the E-tron program, Mr. Stertz said. Unlike the R8 E-tron, the F12 has all-wheel drive and electric motors positioned at the front and rear axles. The car's lithium-ion battery pack is also divided into two separate parts, for better packaging and weight distribution. Development of the F12 was financed with help from the German government and was a collaborative effort of Audi, Bosch and the RWTH Aachen University. Audi said the powertrain, though still under development, was adaptable to a wide range of vehicles, including city cars and S.U.V.'s. Audi's hesitation about selling a purely electric vehicle is nothing new. "Ingolstadt is continuing to move forward on plug-in hybrid E-tron models for volume production," Mr. Stertz said. This conforms with recent statements by Audi executives that champion plug-in hybrid powertrain vehicles over purely electric ones. In an interview with Wheels in June, Jeff Curry, director of e-mobility and sustainability strategy at Audi of America, called plug-in hybrids "the best of both worlds," thanks to their combination of an electric-drive mode and overall range comparable to a normal gasoline- or diesel-powered vehicle. Audi intends to introduce a plug-in hybrid variant of its new A3 model, set to be sold as a sedan in the United States, by 2014. The larger A4 sedan and full-size Q7 crossover are also expected to receive plug-in treatments within the next two to three years.