Tesla Inc.'s former director of battery technology has joined Plenty Inc. to lead the vertical farming startup's plan to build indoor growing rooms around the world.

Kurt Kelty, who joined Tesla in 2006 and left earlier this year, was one of the longest-serving executives at the carmaker led by Elon Musk.

He joins SoftBank Group Corp.-backed Plenty as the senior vice president of operations and market development. Kelty had previously spent more than 14 years at Panasonic Corp.

"At Tesla I was employee number 50 or 60," Kelty said in an interview. "It's a very different company from when I joined. I wanted to figure out where I would contribute to the next big wave. I see my next 10-year run as growing Plenty."

Telecommunications giant SoftBank led a $200 million investment in Plenty in July. The startup is betting that with its technology and the backing of SoftBank Chief Executive Officer Masayoshi Son, it has the connections and capital to accelerate international development.

Plenty says it can yield up to 350 times more produce in a given area than conventional farms — with 1 percent of the water.

At Tesla, Kelty said he spearheaded the Gigafactory battery manufacturing facility near Reno, Nevada, with Musk. Kelty had spent a significant amount of his time in Japan and had previously focused on selling Tesla vehicles there.

At Plenty, Kelty's first priority is getting a mass production facility running in the U.S. Kelty compares the experience to bringing the Roadster — an early Tesla model — to production the first time.