File photograph of General Motors Cadillac Converj concept vehicle at the North American International Auto Show in Detroit

 
File photograph of General Motors Cadillac Converj concept vehicle at the North American International Auto Show in Detroit
General Motors introduces its new Cadillac Converj concept vehicle during press days at the North American International Auto Show in Detroit, Michigan in this January 11, 2009 file photograph. The production of the Cadillac ELR, the first plug-in hybrid electric vehicle from General Motors Co, is to begin in late 2013 at the same plant that makes the Chevrolet Volt, a top GM officical said on October 16, 2012. REUTERS/Rebecca Cook/Files