Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Solid Electrolyte Composed of Poly(vinyl alcohol) and Oligo(3,4-ethylenedioxythiophene) Having a Crosslinked Structure

가교 구조를 갖는 poly(vinyl alcohol)과 oligo(3,4-ethylenedioxy-thiophene)으로 이루어진 고체 전해질

  • Gyo Jun Song (School of Chemical Engineering, Pusan National University) ;
  • Min Su Kim (School of Chemical Engineering, Pusan National University) ;
  • Nam-Ju Jo (School of Chemical Engineering, Pusan National University)
  • 송교준 (부산대학교 응용화학공학부) ;
  • 김민수 (부산대학교 응용화학공학부) ;
  • 조남주 (부산대학교 응용화학공학부)
  • Received : 2024.04.22
  • Accepted : 2024.07.18
  • Published : 2024.08.10
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Abstract

Currently, lithium secondary batteries have been used as medium- or large-sized energy sources such as electric vehicles and energy storage system (ESS) due to their high energy and eco-friendly characteristics. Currently commercialized lithium secondary batteries do not fully meet the demands for high energy density and safety. Many studies on solid electrolytes are being conducted to satisfy these requirements. In order to commercialize a solid electrolyte, it is important to supplement the low ion conductivity and high interface resistance with an electrode compared to the organic liquid electrolyte. Therefore, in this study, oligo(3,4-ethylenedioxythiophene (EDOT)) is added to poly(vinyl alcohol) (PVA), which is a polymer matrix with ion conductivity and sticky characteristics, to decrease the interfacial resistance with the same type of polythiophene (PTh)-based electrode. In addition, the addition of porous silicon dioxide (SiO2) filler improves lithium salt dissociation ability and increases ionic conductivity. And the electrochemical stability of the solid electrolyte, which has been lowered due to additives, is improved by introducing a cross-linked structure using boric acid (BA).

리튬 이차 전지는 고에너지 및 친환경 특성으로 인해 전기 자동차, energy storage system (ESS) 등의 중대형 에너지원으로의 활용이 대두되고 있다. 현재 상용화되고 있는 리튬 이차 전지의 특성은 고에너지 밀도 및 안전성에 대한 요구를 완전히 충족시키지는 못하고 있다. 이러한 요구들을 충족하기 위해 고체 전해질에 대한 많은 연구가 이루어지고 있다. 고체 전해질을 상용화하기 위해서는 유기 액체 전해질에 비해 낮은 이온전도도와 높은 전극과의 계면 저항을 극복하는 것이 중요한 과제이다. 이에 본 연구에서는 이온전도성을 가지면서 수산기를 갖고 있어 전극과의 접착성이 좋은 고분자인 poly(vinyl alcohol) (PVA) 매트릭스에 oligo(3,4-ethylenedioxythiophene) (oligo(EDOT))을 첨가하여 동종의 polythiophene (PTh) 기반 전극과의 계면 저항을 낮추고, 다공성 silicon dioxide (SiO2) filler를 첨가하여 리튬 염 해리능력을 향상시켜 이온전도도를 높인다. 그리고 첨가제로 인해 낮아진 고체 전해질의 기계적 특성을 boric acid (BA)를 사용하여 가교 구조를 도입함으로써 전기화학적 안정성을 향상시킨다.

Keywords

Acknowledgement

이 논문은 부산대학교 기본연구지원사업(2년)에 의하여 연구되었으며, 이에 감사드립니다.

References

  1. J. M. Kim, J. M. Oh, J. Y. Kim, Y. G. Lee, and K. M. Kim, Recent progress and perspectives of solid electrolytes for lithium rechargeable batteries, J. Korean Electrochem. Soc., 22, 87-103 (2019).
  2. BP Technology Transaction, Secondary Battery Industry Analysis Report 2021, 1st ed., 85-98, BT Times, Seoul, Korea (2021).
  3. Y. G. Lee, S. Fujiki, C. H. Jung, N. Suzuki, N. Yashiro, R. Omoda, D. S. Ko, T. Shiratsuchi, T. Sugimoto, S. B. Ryu, J. H. Ku, T. Watanabe, Y. S. Park, Y. Aihara, D. M. Im, and I. T. Han, High-energy long-cycling all-solid state lithium metal batteries enabled by silver-carbon composite, Nat. Energy, 5, 299-308 (2020).
  4. G. S. Kim, Solid electrolyte and all-solid-state battery research and development trends to improve the safety of high-energy secondary batteries, Electr. Electron. Mater., 30, 3221-3223 (2017).
  5. D. Y. Joo, Domestic secondary battery industry status and development tasks, KIET Industrial Economy, 21, 1-12 (2018).
  6. Y. G. Kang and C. J. Lee, Solid polymer electrolyte for lithiumpolymer secondary battery, Polym. Sci. Tech., 14, 396-406 (2003).
  7. Y. J. Wang and D. J. Kim, Crystallinity, morphology, mechanical properties and conductivity study of in situ formed PVdF/LiClO4/TiO2 nanocomposite polymer electrolytes, Electrochim. Acta, 52, 3181-3189 (2007).
  8. W. I. Chae and T. S. Earmme, Polymer electrolyte for lithium ion secondary battery, NICE, 39, 266-271 (2021).
  9. H. Hwang, Electrochemical Analysis, 1st ed., 194-199, Free Academy, Republic of Korea (2007).
  10. S. A. Odhiambo, G. D. Mey, C. Hertleer, A. Schwarz, and L. V. Langenhove, Discharge characteristics of poly(3,4-ethylene dioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) textile batteries; comparison of silver coated yarn electrode devices and pure stainless steel filament yarn electrode devices, Text. Res. J., 84, 347-354 (2014).