Reviewed by Lexie CornerJan 2 2025
A research team from DGIST's Division of Energy & Environmental Technology has developed a lithium metal battery with a "triple-layer solid polymer electrolyte" that enhances fire safety and extends battery lifespan. This innovation has potential applications in electric vehicles and large-scale energy storage systems. The study was published in Small.
Led by Principal Researcher Kim Jae-hyun, the team addressed challenges associated with conventional solid polymer electrolyte batteries. These batteries often suffer from poor electrode contact due to structural limitations and are prone to dendrite formation—tree-like lithium structures that develop during repeated charging and discharging. Dendrites can disrupt battery connections, posing risks of explosions and fires.
The researchers designed a triple-layer electrolyte structure with distinct functional layers to improve safety and performance. The electrolyte incorporates decabromodiphenyl ethane (DBDPE) to prevent fires, zeolite to enhance mechanical strength, and a high concentration of lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) to accelerate lithium-ion transport.
The triple-layer design includes a durable middle layer that increases mechanical strength and soft outer layers that ensure optimal contact with electrodes, enabling efficient lithium-ion movement. This structure enhances energy transfer, improves ion mobility, and effectively prevents dendrite formation.
Compared to conventional batteries, which retain 70–80 % of their capacity after 1,000 charge-discharge cycles, the new battery maintains approximately 87.9 % of its capacity after the same number of cycles. It also incorporates self-extinguishing properties, significantly reducing fire risks.
The battery’s enhanced safety and durability make it suitable for a wide range of applications, from wearable devices and smartphones to electric vehicles and large-scale energy storage systems.
This research is anticipated to make a significant contribution to the commercialization of lithium metal batteries using [solid polymer] electrolytes while providing enhanced stability and efficiency [to] energy storage devices.
Kim Jae-hyun, Principal Researcher, Daegu Gyeongbuk Institute of Science and Technology
This study was funded by the National Research Foundation of Korea's Mid-Career Researcher Program, led by Dr. Kim Jae-hyun, and the Future Materials Discovery Project, led by Professor Lee Jung-ho of Hanyang University.
Journal Reference:
Lim, H., et al. (2024) Triple-Layered Noncombustible PEO-Based Solid Electrolyte for Highly Safe Lithium-Metal Batteries. Small. doi.org/10.1002/smll.202406200