A battery by definition is a collection of cells. So the cell is a little can of chemicals. And the challenge is taking a very high-energy cell, and a large number of them, and combining them safely into a large battery.
The X is an amazing car, but we kind of got carried away with the art and technology. Obviously, you want great art. You want great technology. But we did get a little distracted from our mission, which was to advance the cause of electric vehicles. And it probably delayed us a little bit with the Model 3 as well.