Oxford, UK-based OXIS Energy Ltd. is collaborating with Bye Aerospace of Denver, Colorado, to produce a common lithium-sulfur (Li-S) advanced battery cell for the high-voltage battery pack to be considered for Bye's future electric aircraft. The project will commence in September 2019. OXIS manufactures and produces all aspects and components in the making of the Li-S cell.

“Aviation is one of OXIS' target markets, and in the first instance, Regional Rapid Air Taxi Transportation. A key measure of OXIS' suitability is to be able to consistently produce cells in excess of 400Wh/kg, which are already undergoing evaluation. OXIS expects to achieve 500Wh/kg by early 2020,” said Huw Hampson-Jones, CEO OXIS Energy. OXIS’ Li-S cells and battery systems are more than 50% lighter than the current Li-ion cell and battery systems, with high energy at the power required. The use of the same cell format across batteries will also help customers minimize cost and improve serviceability.

“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. Our collaboration with OXIS is separate from the current eFlyer 2 agreements and intentions we have with confirmed and our future supply chain partners,” said George Bye, CEO of Bye Aerospace. Bye Aerospace is developing FAR 23-certified general aviation aircraft, starting with the eFlyer 2, for the flight training role.

Bye Aerospace is working with OXIS on the Li-S battery cell characteristics to significantly improve the eFlyer 4 and future air taxi aircraft designs' performance.

In ground tests in Europe, Li-S has demonstrated a significant improvement in simulated flight duration compared with Lithium NMC; it will now undertake a further series of tests which will indicate OXIS Li-S performance.

During the next 18 months, the aim is to move toward production of commercial cells and battery systems to meet the volume roll-out criteria set by Bye Aerospace.