As it turns out, I was more right than I realized.

This week, years after that first sighting, Tesla announced plans for what it calls the “Gigafactory,” a 10-million-square-foot plant for making car batteries. The company hopes that the sheer scale of the operation, combined with the inventiveness of its engineers, will bring battery prices down far enough to finally bring its electric cars into the mainstream.

But it’s not just the prospect of a gasoline-free future that has sparked such excitement about the Gigafactory. The same basic lithium-ion tech that fuels Tesla’s cars also runs most of today’s other mobile gadgets, large and small. If Tesla really produces batteries at the scale it’s promising, cars could become just one part of what the company does. One day, Tesla could be a company that powers just about everything, from the phone in your pocket to the electrical grid itself.