국립 부경대학교

PKNU prof. Cho Kie-Yong's team developed a separator that suppresses thermal runaway in secondary batteries

- giving new self-extinguishing capabilities by coating separator of a lithium-ion battery with a fluorine-based polymer

- published in the international academic journal <Journal of Materials Chemistry A> and selected as the cover paper

The research team led by professor Cho Kie-Yong (industrial chemistry) at Pukyong National University announced that they had developed a separator that suppresses 'thermal runaway' of lithium-ion secondary batteries used in electric vehicles.

The research team, consisting of professor Cho Kie-Yong, Park Jae-Won, a master's researcher, Kwon Young-Je, a doctoral student at Pukyong National University, and professor Yoon Jeong-Sik from Incheon national university, developed a separator that improves the thermal stability of lithium-ion batteries and suppresses flames by introducing self-extinguishing ability.

The research team attempted to coat a commercial polypropylene separator with a functionalized fluorine-based polymer and developed this separator using a cross-linking (reaction that creates new chemical bonds in chain-like natural and synthetic polymers to form a three-dimensional network structure).

Recently, the development of transportation based on hydrogen cells or lithium-ion batteries has been underway to reduce carbon emissions, but the fatal drawback of electric vehicles manufactured based on lithium-ion batteries is safety concerns such as thermal runaway due to ignition of organic electrolyte.

The separator for lithium-ion secondary batteries developed by professor Cho's research team is expected to suppress such thermal runaway phenomenon by not only improving thermal stability but also having self-extinguishing capabilities.

The fluorine-based polymer coating layer improves the high-temperature safety characteristics of the separator by suppressing thermal shrinkage of the separator at high temperatures through the crosslinking reaction of the polymer. In addition, when burning, the electrolyte and coating layer of the separator decompose together, showing self-extinguishing ability by suppressing continuous ignition in the event of a battery fire through sub catalytic extinguishment.

The first author of the paper researcher, Park Jae-Won, said, "we hope to not only resolve user's concerns about the safety of lithium-ion batteries through our research, but also enable lithium-ion batteries to be used in more diverse fields for an eco-friendly future."

As for this research, it was conducted with support from the Regional innovation project (RIS) based on cooperation between local governments and universities, and the research project supported by the Ministry of trade, industry and energy and the National research foundation and the research, 'Fluorine-rich modification of self-extinguishable lithium-ion battery separators using cross-linking networks of chemically functionalized PVDF terpolymers for highly enhanced electrolyte affinity and thermal-mechanical stability' was published in the internationally renowned journal <Journal of Materials Chemistry A> (IF 11.9 / JCR top 8.8%) on January 28 and was also selected as the cover paper. <Pukyong Today>

△ The research team led by professor Cho Kie-Yong (prof.Cho Kie-Yong, Park Jae-Won, Kwon Young-Je, Kim Se-Hoon, Bae Ji-Woo, prof. Lee Min-Jeong, and prof. Yoon Jeong-Sik from the left)