Bye Aerospace Explores Lithium-Sulfur Battery Solution

The company aims for a new technology for its larger aircraft.

The eFlyer 2 taxis at Centennial Airport in Colorado on July 30.Bye Aerospace

Most folks are quickly gaining familiarity with lithium-ion batteries as they play an ever-increasing part in our lives. However, when it comes to delivering power for an airplane, where weight is critical, they reach a limit to their utility.

That's why George Bye, CEO of Bye Aerospace, is excited to share the company's latest partnership with OXIS Energy. OXIS, based in Abingdon, England, has been developing a different type of battery technology, using lithium-sulfur (Li-S) cells for the storage of energy. The cells stand to achieve a higher energy density than commensurate lithium-ion (Li-ion) cells—which translates into lower weight. "Energy density is almost twice what we have in the most current, modern lithium-ion battery," as Bye shared with Flying magazine.

Bye Aerospace will work with OXIS to “get the battery out of the lab and onto the airplane.” He estimates that they will spend about a year or a year-and-a-half of testing and development to take the already mature technology into an operational place.

The four-seat eFlyer 4 is the initial target for the new battery system, followed by future larger aircraft projects suitable for air taxi operations. While the eFlyer 2 is focused on the training market, with a 3-hour endurance and range enough for the cross-country flights towards the private pilot certificate, the eFlyer 4 aims at flying longer. In its current state of development, it’s projected to fly 200 to 300 nm, or for roughly 4 hours. With the Li-S technology, Bye sees a potential for a 7- or even 8-hour endurance. “If true,” says Bye, “it’s a gigantic technical advantage,” and will help the airplane reach its full market potential.

The eFlyer 2 will stay on course with its current development plan, agreements, and supply chain, according to a company release.