Obama says US must shift cars, trucks off of oil - Article Photos 2/6

President Barack Obama listens to Research Engineer Henning Lohse-Busch as he explains electric car technology during the president's tour of the Argonne National Laboratory in Argonne, Ill., Friday, March 15, 2013. Argonne is the first US science and engineering research national laboratory, and it remains on of the nation’s largest. (AP Photo/Pablo Martinez Monsivais)