SK On said on Thursday that it has developed an oxide solid electrolyte with high ion conductivity.
The South Korean battery maker, together with Dankook University Professor Hee Jung Park, coated a controllable additive on Li-La-Zr-O that improved the ion conductivity by 70% than before (1.7 mS/cmž).
The findings were published in Advanced Functional Materials issue IF19.9, SK On said.
While increasing the speed of lithium-ion conductivity decreases stability, the company said it used a technology that uniformly controls the microstructure of LLZO.
Conventional solid electrolyte suffers performance drop when exposed to water and carbon dioxide for a long time but this electrolyte showed high stability, SK On said.
SK On is currently developing both polymer oxide and sulfide solid-state batteries.
It is aiming to produce prototypes of them by 2026 and start mass production in 2028. At its lab in Daejeon, a pilot line for the batteries is being constructed that is set to go live next year.
While oxide solid electrolyte has lower ion conductivity than sulfide electrolyte, it has less reaction to cathode materials and can control lithium dendrite formations. The graphite anode can be replaced with lithium metal.
Battery capacity can also be significantly increased by up to 5.5V compared to lithium-ion battery’s 4.3V.