Airbus shifts its battery chemistry and supplier for its high-altitude Zephyr drone

December 19, 2018 | Case Study

When Airbus announced that its solar- and battery-powered high-altitude UAV Zephyr had flown for 25 days straight and broken the world record for longest continuous flight, we assumed that Zephyr had continued to use Sion Power's lithium-sulfur (Li-S) batteries given its three-year Li-S supply deal with the company. However, four months after Airbus announced the record-breaking flight, Amprius clarified that the flight was powered not by Sion's Li-S batteries, but rather by Amprius' silicon nanowire anodes composed of pure silicon. Amprius claims that batteries equipped with its silicon nanowire anodes can achieve 1,200 Wh/L and 435 Wh/kg, which is indeed much higher than the 330 Wh/L and 400 Wh/kg that Sion achieves with its Li-S batteries.