Sunday 7th January 2007

General Motors introduced the Chevy Volt plug-in hybrid concept car at North American International Auto Show, becoming the first-ever series plug-in hybrid concept car shown by a major car manufacturer. The Volt concept vehicle had four doors with a rear liftgate and seating for four passengers. This was a significant change in design when compared to the General Motors EV1 of the 1990s, which only seated two to reduce weight and to make the necessary room for the lead-acid battery pack. The top speed was also increased on the Volt, from the electronically limited 80 miles per hour (130 km/h) to 100 miles per hour (160 km/h).The Volt operated as a pure battery electric vehicle until its plug-in battery capacity dropped to a predetermined threshold from full charge. From there its internal combustion engine powered an electric generator to extend the vehicle’s range as needed. When the engine was running it could be periodically mechanically linked (by a clutch) to a planetary gear set, and hence the output drive axle, to improve energy efficiency. The Volt’s regenerative braking also contributed to the on-board electricity generation.