Toyota will invest another $500 million in eVTOL maker Joby to support the certification and production of its S4 electric air taxi. The Japanese automaker was an early investor in the company, having invested $394 million in 2020. Toyota will now own about 22 percent of Joby's common shares.

Joby CEO JoeBen Bevirt, explained that the investment builds on seven years of collaboration between the two companies. "The knowledge and support shared by Toyota has been instrumental in Joby's success," he said in a statement. "Both companies are very committed to shaping this next generation of transportation as we move to the air for our daily transportation needs."

Besides cash, Toyota has been providing manufacturing and engineering expertise as Joby ramps up production in a new facility. It will also supply key powertrain and other components for the electric aircraft. The five-seat S4 will have a range of about 100 miles on a single battery charge.

Joby recently completed its third aircraft, noting in August that the fourth of five FAA certifications were now complete. It plans to have its eVTOL in service by 2025 and has been working on developing infrastructure networks in the U.S. and other regions of the world. It has been particularly active in the United Arab Emirates, which could have the first working eVTOL networks.

Joby and another California-based competitor, Archer, are considered the primary air-taxi companies in the US, while Lilium and Volocopter in Germany and Vertical Aerospace in the U.K. are leaders on the other side of the Atlantic.

In 2022, Delta Air Lines invested $60 million in Joby for a 2 percent equity stake. Joby last year delivered the first eVTOL to Edwards Air Force Base as part of its partnership with the U.S. Air Force's $131 million AFWERX Agility Prime contract. "The longstanding support of the DOD and NASA has been critical to the rapid development of electric aviation and eVTOL aircraft," Bevirt said at the time. "It demonstrates how successful public-private partnerships can bring new technology to life at speed."

Bevirt founded Joby in 2008 to help relieve carbon pollution and crowded urban highways. But he largely kept the company in stealth mode until 2022, when it went public.

Joby then began to do continuous "road shows" in different countries to introduce the technology to the general public. It is currently showcasing its eVTOL in New York's Grand Central Station until October 5.