South Korean company SK On has announced that it has co-developed a polymer electrolyte for lithium metal batteries that can be operated at room temperature. The electrolyte, called “Single Ion-Conducting Polymer Electrolyte” (SIPE), was developed in collaboration with a research team at the University of Texas. SK On expects SIPE to make a significant contribution to improving the performance of solid-state batteries and accelerating their development.
Use at room temperature
SK ON sees polymer electrolytes as the next generation of low-cost, easy-to-manufacture materials for solid-state batteries. However, compared to oxide- and sulfide-based electrolytes, polymer electrolytes have lower ionic conductivity. As a result, they generally operate only at high temperatures of 70°C to 80°C. Compared to existing polymer electrolytes, however, SIPE has increased the ionic conductivity at room temperature tenfold and the lithium ion transfer number fivefold.
High mechanical strength
Another advantage cited by the company is the increased stability of the solid electrolyte interphase (SEI), which suppresses dendrite formation. High mechanical strength is said to enable mass production. When applied to next-generation solid-state hybrid batteries, SK On expects this to improve charging speed and low-temperature performance.