Tesla's founders on Elon Musk and the early days

Elon Musk is the most famous CEO of Tesla, but he's not the company's founder. The original executives, Martin Eberhard and Marc Tarpenning, founded the company in 2003. CNBC sat down with them to talk about the idea for Tesla Motors, the battery, Elon Musk and building its first car, the all-electric Roadster.