SK On has successfully co-developed a groundbreaking polymer electrolyte for lithium-metal batteries, enabling operation at room temperature.
This achievement, a result of collaboration with the late Professor John B. Goodenough’s team at the University of Texas, holds the potential to revolutionize solid-state battery performance and accelerate their development.
Nobel Laureate’s Legacy in Battery Technology
Professor Goodenough, a pioneer in battery technology and the oldest Nobel Prize laureate, had been working with SK On on this project until his passing.
The research, now published in the Journal of Electrochemical Society, showcases a significant leap forward in the field.
This novel polymer electrolyte, SIPE (single-ion conducting polymer electrolyte), significantly improves ionic conductivity and lithium-ion transference number compared to existing polymer electrolytes.
It achieves a tenfold increase in room temperature ionic conductivity and a nearly fivefold increase in lithium-ion transference number, enabling operation at room temperature.
Improved Battery Performance and Safety
The enhanced ionic conductivity and lithium-ion transference number translate to improved battery output and charging performance.
Experimental results demonstrate that batteries with SIPE maintain 77% of their discharge capacity even under high-rate charging and discharging, minimizing capacity loss commonly associated with high-rate charging in solid electrolytes.
The stability of the solid electrolyte interphase (SEI) has also been enhanced, effectively suppressing dendrite formation. This is a crucial step in commercializing lithium-metal batteries, which offer significantly higher energy density than traditional graphite-based cathodes.
Mass Production and Thermal Stability
SIPE’s high mechanical durability facilitates mass production, and its exceptional thermal stability allows it to withstand temperatures exceeding 250°C.
When integrated into next-generation hybrid solid batteries, it promises to enhance charging speed and low-temperature performance.
SK On’s Head of Next Generation Battery R&D Office, Kim Tae-kyung, expressed optimism about the research findings, stating that they expect to expedite the development of solid-state batteries utilizing polymer electrolytes.
This breakthrough reinforces SK On’s commitment to leading the next-generation battery market.
Ongoing Development of All-Solid-State Batteries
SK On continues to pursue the development of two types of all-solid-state batteries: polymer-oxide composites and sulfide-based batteries.
The company aims to produce pilot prototypes in 2025 and 2026, respectively, with commercial prototypes targeted for 2028 and 2029. The construction of a sulfide-based next-generation battery pilot plant at their Battery Research Institute in Daejeon, South Korea, is expected to be completed in the second half of next year.