The first Tesla I ever saw was stripped down to the chassis, a bare-metal incarnation of the company’s flagship electric Roadster on display at an event in Silicon Valley. Without the need for an internal combustion engine, the two-seater’s petite frame was dominated by a huge battery. My first thought: “This looks like a giant cell phone on wheels.”

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.