 The Chevrolet Volt concept car debuted at the January 2007 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 battery pack size was reduced , from about 10 @.@ 6 cu ft ( 300 L ) in volume in the EV1 , to 3 @.@ 5 cu ft ( 100 L ) in the Volt . 
