Almost every day old iPhones and other used personal electronics arrive by the truckload at a warehouse in Carson City, Nev., where workers crack them open, pull out their batteries and strip them for raw materials.
To JB Straubel, one of the brains behind Tesla Inc., TSLA -1.13% that refuse holds the key to driving the electric car revolution forward—and making the vehicles affordable enough for everyone to own one.
Mr. Straubel, Tesla’s longtime chief technology officer, pioneered the lithium-ion battery powertrain design that helped propel the Silicon Valley company to what is now the highest valuation in the car industry. Since leaving Tesla about a year ago, he has been trying to solve a problem created by that success: Where to find all the nickel, cobalt and lithium needed to make the batteries that power Tesla’s cars and their growing list of rivals.
Extracting those materials from nature, through mining and other processes, is costly and difficult, and production is lagging far behind expected demand. Mr. Straubel’s company, Redwood Materials, is taking a different tack, quietly aiming to build the biggest car battery-recycling operation in the U.S. The 44-year-old is betting that he can perfect a fast and efficient way of collecting and repurposing those materials to disrupt the centuries-old mining industry.