The high-altitude long-range solar unmanned aerial vehicle (EAV-3) developed by the Korea Aerospace Research Institute, loaded with LG Chem’s lithium-sulfur batteries, successfully conducted a stratospheric flight test.

The stratosphere is the atmosphere between the troposphere (surface to 12 km) and the middle layer (50 to 80 km), with a height of 12 to 50 km.

EAV-3 is a small aircraft that can fly for a long time through solar energy and batteries in the stratosphere at a height of 12km or more. Use the solar panels on the wings to charge, fly with solar cells and battery power during the day, and fly with the batteries charged during the day at night. The EAV-3 has a wingspan of 20m and a fuselage of 9m.

In this flight test, EAV-3 set a record high in the stratospheric flight of Korean domestic drones with a flight altitude of 22km. During the 13-hour flight, the UAV carried out a stable flight for up to 7 hours in the stratosphere at an altitude of 12km to 22km.

Lithium-sulfur batteries, as one of the new generation batteries to replace lithium batteries, use light materials such as sulfur-carbon composite cathode materials and lithium metal anode materials, and their energy density per unit weight is more than 1.5 times that of existing lithium batteries. The advantage is that it is lighter than the existing lithium battery and has better price competitiveness because it does not use rare metals.

LG Chem said that in the future it will produce more lithium-sulfur battery trial products and conduct multi-day long-distance flight tests. It also plans to mass-produce lithium-sulfur batteries with energy density more than twice the existing lithium batteries after 2025.