Lithium-Sulfur Batteries Power High-Altitude Aircraft For 11-Day Flight
Lithium sulfur (Li-S) batteries reach another milestone as the Airbus Defense and Space Zephyr 7 prototype High Altitude Pseudo-Satellite (HAPS) aircraft finished a southern hemisphere winter weather flight of over 11 days duration controlled by satellite communications.
Because of short winter days, along with over 250 hours of flight, Zephyr 7 flew longer on batteries than on the solar array.
The ultimate goal for High Altitude Pseudo-Satellite (HAPS) aircrafts is year-round capability.
The Zephyr 7 is a solar/battery powered all-electric UAV equipped with Sion Power (Li-S) batteries. Energy density of those cells stand at 350 Wh/kg. The whole aircraft’s weight is just over 110 lbs. (50 kg) and it has a wing span of 70 feet (22.5 m).
“The custom built Li-S battery pack was designed and assembled by Sion Power in Tucson, Arizona. The battery utilized Sion’s unique, high specific energy Li-S cells which provide 350 Wh/kg, the highest available for a rechargeable battery. The Li-S battery pack was carefully engineered to minimize total pack weight. Advanced electronic controls maintained the battery condition throughout the flight.”
“Once launched, Zephyr can remain above a region for weeks delivering persistent services at a fraction of the cost of satellites and is significantly more cost effective than other conventionally powered manned or unmanned aircraft. This latest flight is part of an ongoing program to develop Zephyr into a year-round capability and provided the data which will be used to refine the design for the Zephyr 8, the next generation of HAPS.”
Sion Power’s CEO, Dr. Dennis Mangino stated:
“This flight represents a further major accomplishment for Sion’s lithium sulfur technology proving the viability of our high energy, rechargeable battery system. As a winter flight, the aircraft flew longer on the batteries than on the solar array, a world first.”
Jens Federhen, head of the Airbus Zephyr program, commented:
“The performance of the Sion Li-S battery was excellent and the Zephyr was able to exploit the full capacity of the battery due to the high reliability and consistency of the cells, essential for this winter flight. Sion’s Li-S batteries are an enabling technology for the Zephyr program and we look forward to joint future flights.”