SK On closer to 'dream batteries' with solid electrolytes

SK On's prototype of solid-state batteries unveiled at the InterBattery 2023 in March [SK ON]

SK On has developed high-conductivity solid electrolytes and is a step closer to developing solid-state batteries, touted as “dream batteries” for their high energy density and safety.

The Korean battery maker said Thursday it successfully developed solid electrolytes that can possibly increase the energy density of EV batteries by 25 percent under a joint development agreement with a research team led by Professor Park Hee-jung, who teaches materials science at Dankook University. Patent applications for the technology have been completed both in Korea and overseas countries.

Solid electrolytes are critical in making solid-state batteries and are yet to be commercialized. Liquid electrolytes, currently the most common form, are often blamed for fires in EVs.

The developed solid electrolytes improved the conductivity by 70 percent, SK On said. Low conductivity, which directly affects the power of the EVs, has been referred to as one of the biggest formidable obstacles that will hinder quick commercialization.

Battery capacity can be increased by up to 25 percent, the company added. The electrolytes can be also used as a material to solidify lithium-sulfur batteries and lithium-air batteries, which are considered as the next-generation batteries.

"The solid electrolytes with high conductivity and safety will cause ripple effects in the industry as the latest innovative technologies to develop high-quality solid-state batteries," according to Choi Kyoung-hwan, head of SK On's next-generation battery department.

SK On aims to produce a solid-state battery pilot product by 2026 and commercialize the batteries in 2028. Its pilot plant is under construction in Daejeon and will be completed in 2024.

BY SARAH CHEA [chea.sarah@joongang.co.kr]