Tesla May Have Invented a Million-Mile Electric Car Battery

Is Elon Musk’s tech for vehicles built to last 76 years, or the key to a driverless car-on-demand future? Yes.

Illustration: Giacomo Bagnara

Since Edison a century ago, the world of batteries has been riven with exaggeration and fibs. U.S. university and private labs routinely announce purportedly important new leaps…