British battery specialist Oxis Energy is cooperating with US aircraft manufacturer Bye Aerospace to develop lightweight lithium-sulfur cells for battery packs in future Bye Aerospace electric aircraft.
The joint project starts in September and aims to achieve a battery cell energy density of 500 Wh/kg by early 2020. Initially, however, 400 Wh/kg cells will be installed, while Bye Aerospace is to receive the first 400 kWh of lithium-sulfur (Li-S) cells this year. The project is scheduled to run for a total of five years.
“Our Li-S cells and battery systems are ideally suited for aviation,” says Huw Hampson-Jones, CEO of Oxis Energy. “They are over 50% lighter than the current Li-ion cell and battery systems… The use of the same cell format across batteries will also help our customers to minimise cost and improve serviceability.”
With the eFlyer 2 and eFlyer 4, Bye Aerospace already offers two small electric aircraft. The electric motors are powered by Siemens technology, among others. The Norwegian OSM Group has already purchased 60 eFlyer 2 and BlackBird purchased 110 eFlyer 4. According to the company, Bye Aerospace has tallied 624 purchase confirmations in total. Together with Uber Elevate, Bye is also working on a project for an electric vertical take-off aircraft (VTOL).
“New Li-S battery cells from Oxis have the potential to greatly enhance the quality, cost and performance of eFlyer 4 and our other future aircraft projects,” said George Bye, CEO of Bye Aerospace. “The average age of the global market for Turboprop fleet is 28 years. OXIS has the potential to provide a Li-S battery cell that is truly a game-changer.”
Oxis is currently planning to manufacture the Li-S cells in Brazil on a large scale. Pre-products for the cathodes and electrolytes are to be made in Wales, UK. The company has not yet specified the exact capacities of the two plants. Among the investors is Safran, with whom Oxis also wants to cooperate in the development of battery systems for commercial aircraft.