Tesla's Model S appears to still be on track for its planned 2012 launch and will be using battery technology offering the highest energy density "in the world." Built in Panasonic's new fab in Suminoe, Japan, these 3.1Ah cells (you can just about see one of them being held by the two corporate types above) will be manufactured at a rate of more than 300 million per year. Considering each car would require a few more than 6,000 of them for its full energy storage, that means Tesla would be able to churn out about 48,000 Model S sedans per year. Then again, the company has only sold about 1,000 units of its Roadster so far, so we doubt it'll be pushing Panasonic's max production capacity any time soon. Still, good to know things are progressing in the right direction.