The KERS setup and the concept road car both used a lithium ion battery pack. According to the diagram published in the magazine, the road car will have the battery and the power electronics mounted on either side of the rear transaxle. An electric motor is incorporated into the transaxle itself. If the road car is similar to the race car, this will essentially be a mild hybrid system providing automatic start-stop, regenerative braking and electric boost. Judging the situation by the battery size, the Ferrari won't offer any pure electric propulsion. The system is expected to boost urban driving mileage by over 30 percent from the current 8.7 mpg (U.S.) to a slightly less miserable 13.8 mpg. Thanks to Daniele for the tip!