LG Chem, Korean’s largest chemical company, has produced a prototype lithium-sulfur battery that completed multiple high-altitude flights in a solar-powered unmanned aerial aircraft (UAV), dubbed EAV-3. The aircraft was made by the Korea Aerospace Research Institute (KARI).
A solar-powered UAV is a drone that can recharge itself during flight via solar power. This feature is useful because the aircraft could charge their battery during the day and then use it to stay in the air at night. Efforts are actively underway worldwide to develop this technology to be applied to aircraft, primarily because it can perform tasks in an eco-friendly manner at a lower cost.
On August 30, LG Chem installed the lithium-sulfur battery (Li–S battery) on an EAV-3 at the KARI site in Goheung and conducted a 13-hour flight test from 8:36 AM to 21:47. LG Chem is the first firm in Korea to conduct flight tests using a Li–S battery.
The EAV-3 is 9m long, with a wingspan of 20m, and weighs around 21 kg (46 lbs). The UAV is equipped with ultra energy-dense cells that are denser than advanced lithium-ion batteries currently available on the market. In fact, the company claims that the energy-density is up to 50% higher!
The flight tests revealed “a stable charge/discharge function of a lithium-sulfur battery, the next generation battery, in the extreme environment of the stratosphere”, at freezing temperatures of -70°C (-94°F) and near ‘vacuum state’ atmospheric pressures of 1/25 of one at ground level.
What is the stratosphere? It’s one of Earth’s atmospheric layers from 12 to 50 km above sea level, between the troposphere (the ground to 12km) and the mesosphere (50 to 80km). During the flight tests, the EAV-3 achieved a new record of flying at the highest altitude in the stratosphere in South Korea, at 22 km (13.7 miles), which is impressive for a domestic unmanned aircraft.
LG Chem plans to introduce the next-generation lithium-sulfur batteries to the market and begin “mass-producing” them by 2025.
