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.

He oversaw development of the Tesla Roadster. Musk is also a member of the board of trustees of the California Institute of Technology (Caltech).

Musk holds a bachelor's degree in Business from the The Wharton School and a second bachelor's degree in Physics from University of Pennsylvania School of Arts and Sciences. He is currently the CEO and Chief Designer of SpaceX CEO and Product Architect of Tesla Motors and Chairman of SolarCity. While at those companies he oversaw the construction of the first electric car of the modern era the Tesla Roadster a private rocket known as Falcon 9/Dragon and the Internet payment system PayPal.