Researchers at the Daegu Gyeongbuk Institute of Science and Technology (DGIST) have developed a lithium metal battery with a triple-layer solid polymer electrolyte, significantly enhancing fire safety and extending the battery’s lifespan. Led by Principal Researcher Jae-hyun Kim from the Division of Energy & Environmental Technology, the team’s innovation holds promise for applications in electric vehicles and large-scale energy storage systems.
Traditional solid polymer electrolyte batteries often suffer from performance issues due to structural limitations that hinder optimal contact between the electrodes. A major challenge in these batteries is the formation of dendrites—lithium structures that grow during repeated charging and discharging cycles. These dendrites can disrupt battery connections and pose serious safety risks, including fires and explosions.
To address these issues, the DGIST research team designed a triple-layer electrolyte structure, with each layer serving a specific function to enhance safety and efficiency. The electrolyte incorporates decabromodiphenyl ethane (DBDPE) as a flame retardant to prevent fires, zeolite to strengthen the electrolyte’s structure, and a high concentration of lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) to facilitate rapid movement of lithium ions.
The innovative structure features a robust middle layer that increases mechanical strength, sandwiched between softer outer layers that ensure excellent contact with the electrodes. This design promotes smooth lithium ion flow, enhances energy transfer rates, and effectively prevents the formation of dendrites.
Experimental results demonstrated that the new battery retains approximately 87.9% of its performance after 1,000 charging and discharging cycles. This represents a significant improvement over conventional high-energy density batteries, which typically maintain about 70-80% of their performance after the same number of cycles. Notably, the battery’s self-extinguishing capability in the event of a fire significantly reduces fire risks, enhancing overall safety.
“This research is expected to contribute substantially to the commercialization of lithium metal batteries using solid polymer electrolytes,” said Dr. Kim. “Our goal is to provide energy storage devices with enhanced stability and efficiency.”
The study was supported by the Future Materials Discovery Project and the Mid-Career Researcher Program of the National Research Foundation of Korea. The findings were published as the cover article in the journal Small, published by Wiley.
More Information: Triple-Layered Noncombustible PEO-Based Solid Electrolyte for Highly Safe Lithium-Metal Batteries – Heesoo Lim et al., Small.
Source: DGIST News
