Panasonic Corporation and Tesla Motors today announced that Panasonic has invested $30 million in Tesla. The investment was made through the purchase of Tesla common stock in a private placement at a price of $21.15 per share. The investment builds upon a multi-year collaboration of the two companies to accelerate the market expansion of the electric vehicle.

Panasonic is the world’s leading battery cell manufacturer and a diverse supplier to the global automotive industry. Tesla currently uses Panasonic battery cells in its advanced battery packs and has collaborated with Panasonic on the development of next generation battery cells designed specifically for electric vehicles. While Tesla’s current battery strategy incorporates proprietary packaging using cells from multiple battery suppliers, Tesla has selected Panasonic as its preferred lithium-ion battery cell supplier for its battery packs.

“Panasonic aims to be the number one Green Innovation Company in the Electronics Industry by 2018, the 100th anniversary of our founding,” said Naoto Noguchi, President of Energy Company, a unit of Panasonic responsible for the battery cell business. “Our sophisticated lithium-ion battery cell technology, combined with Tesla’s market-leading EV powertrain technology, helps us fulfill this goal by promoting sustainable mobility. We are proud to strengthen our relationship with Tesla Motors.”

“It is an honor and a powerful endorsement of our technology that Panasonic, the world’s leading battery cell manufacturer, would choose to invest in and partner with Tesla,” said Tesla CEO and cofounder Elon Musk. “Panasonic offers the highest energy-density cells and industry-leading performance with cutting edge Nickel-type cathode technology. Our partnership with them will enable us to further improve our battery pack while reducing cost.”

In addition to producing its own vehicles, Tesla also builds electric powertrains, including battery packs, for other automobile manufacturers. Panasonic and Tesla have agreed to explore joint marketing and sales of battery packs that would be designed and assembled by Tesla using Panasonic’s battery cells.