According to an article in the financial section of today's newspaper, both Tesla and Panasonic have announced that Panasonic will expand the delivery of its "automotive-grade" lithium-ion battery cells to a total of nearly 2 billion battery cells through 2017. It was noted that in November 2010 Panasonic purchased $30 million of Tesla's common stock.
I found this paragraph particularly interesting: " Practically every company that makes a lithium-ion battery has sent its cells to Tesla, which puts them through rigorous testing, with a focus on extending their life and safety. In the cell characterization lab at Tesla's Palo Alto headquarters, nearly 1,000 cells from various vendors are tested against one another. In other labs, battery packs are subjected to stress tests that include freezing temperatures and high humidity."
Tesla expects to deliver 21,000 Model S sedans worldwide this year. Also mentioned was that there are now 16 Supercharger stations along I-5 and Highway 101, between Vancouver and San Diego. A total of 31 stations have been constructed in North America so far.