Fluoride-free batteries: protecting the environment and increasing efficiency

A research team led by Professor Soojin Park and Seoh Nam from POSTECH’s Department of Chemistry, in collaboration with Hansol Chemical’s Battery Materials R&D Center, has developed a new fluorine-free binder and electrolyte designed to advance environmentally friendly, high-performance battery technology . Their research results were recently published in the journal Journal of Chemical Engineering, international journal of chemistry.

As environmental concerns increase, the importance of sustainable materials in battery technology is growing. Traditional lithium batteries rely on fluorinated compounds such as polyvinylidene fluoride (PVDF) and lithium hexafluorophosphate (LiPF) binders_6, LP) salts. However, this “PVDF-LP” system releases highly toxic hydrogen fluoride (HF), which reduces battery performance and life. Additionally, PVDF is not biodegradable, and with tightening European Union (EU) regulations on PFAS, the use of these substances is expected to be banned by 2026.

Scientists from POSTECH and Hansol Chemical have developed a non-fluorinated battery system to comply with upcoming environmental regulations and increase battery performance. They created lithium perchlorate (LiClO₄LC-based electrolyte replacing fluorinated LP electrolytes with a non-fluorinated aromatic polyamide (APA) binder using proprietary Hansol Chemical technology. This innovative “APA-LC” system is completely free of fluorine compounds.

The “APA binder” strengthens the bond between the active cathode material and the aluminum current collector, preventing electrode corrosion in the electrolyte and significantly extending battery life. Additionally, the “LC system” enriched with lithium chloride (LiCl) and lithium oxide (Li₂O) lowers the energy barrier at the interface, promoting ion migration, leading to faster lithium diffusion and excellent output performance compared to the existing LP system. Overall, the APA-LC system exhibited greater oxidation stability than the conventional PVDF-LP system and maintained 20% higher capacity after 200 cycles at a high charge/discharge rate of 1°C, in the range of 2.8–4.3V in coin cell test .

The research team used the APA-LC system to produce a 1.5 Ah (amp-hour) high-capacity bag cell. The cell retained excellent discharge capacity and showed good performance during fast charging tests. This marks the world’s first successful demonstration of a battery system that is fully scalable and practical, made entirely of non-fluorinated materials and without any fluorinated compounds.

Professor Soojin Park of POSTECH expressed the importance of the research, saying: “We have not only replaced fluorinated systems; We have proven that they maintain high performance and exceptional stability.” He continued: “Our solution will help increase the sustainability of the battery industry by facilitating the transition to non-fluorinated battery systems while ensuring environmental compliance.”

Managing Director Young-Ho Yoon of Hansol Chemical’s Secondary Battery Materials business noted, “By addressing regulatory issues surrounding PFAS, we have positioned ourselves in the global cathode binder market, which is expected to reach KRW 1.7 trillion by 2026.” He added: “Continued research will solidify our position as a leading supplier of environmentally friendly secondary battery materials.”