이온성 액체 복합 Poly(ethylene oxide)(PEO) 고체 고분자 전해질의 전기화학적 특성
Electrochemical Properties of Ionic Liquid Composite Poly(ethylene oxide)(PEO) Solid Polymer Electrolyte
1
조회
0
다운로드
2
인용
0
참고문헌
키워드
초록
본 연구에서는 리튬 고분자 이차전지의 안정성과 전기화학적 특성을 향상시키기 위하여 poly (ethylen oxide)(PEO) 를 lithium bis (trifluoromethanesulfonyl)imide, N-butyl-Nmethylpyrrolidinium bis (trifluoromethanesulfonyl)imide 와 블렌딩-가교 법으로 복합화시켜PEO-LiTFSI-Pyr14TFSI 고분자 전해질을 제조하였다. 전기화학적 산화 안정성 테스트에서 PEOLiTFSI- Pyr14TFSI 복합 고분자 전해질은 비록 4.4 V에서 약간의 산화곡선을 보이지만 5.7 V까지안정하였다. PEO-LiTFSI-Pyr14TFSI 고분자 전해질은 온도가 증가할수록 이온전도도가 증가하며, PEO계열의 고분자 전해질의 특성상 상온에서 10-6S cm-1로 낮지만 70℃ 에서는 10-4S cm-1까지증가 하였다. 리튬 고분자 전지의 전기화학적 특성을 측정하기 위해 LiFePO₄ 양극, PEOLiTFSI- Pyr14TFSI 복합 고분자 전해질, 리튬 음극으로 전지를 구성하였으며 0.1 C의 전류밀도에서 방전 용량이 30℃ 에서 40 mAh g-1, 40℃ 에서는 69.8 mAh g-1, 50℃ 에서는 113 mAh g-1 을 나타내 온도의 증가에 따라 방전 용량이 증가함을 알 수 있었다. PEO-LiTFSI-Pyr14TFSI 복합 고분자 전해질은 LiFePO4양극과 함께 50도에서 가장 우수한 충-방전 성능을 보여주었다.
Abstract
In this study, we prepared an ionic liquid composite solid polymer electrolyte (PEOLiTFSI- Pyr14TFSI) with poly(ethylen oxide), lithium bis(trifluoromethanesulfonyl)imide, N-butyl- N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide by blending-cross linking process. Although the PEO-LiTFSI-Pyr14TFSI composite solid polymer electrolyte displayed a small peak at 4.4 V, it had high electrochemical oxidation stability up to 5.7 V. Ionic conductivity of the PEO-LiTFSI-Pyr14TFSI composite solid polymer electrolyte increased with increasing temperature from 10-6 S cm-1 at 30℃ to 10-4 S cm-1 at 70℃. To investigate the electrochemical properties, the PEO-LiTFSI-Pyr14TFSI composite solid polymer electrolyte assembled with LiFePO4 cathode and Li-metal anode. At 0.1 C-rate, the cell delivered 40mAh g-1 for 30℃, 69.8mAh g-1 for 40℃ and 113 mAh g-1 for 50℃, respectively. The PEO-LiTFSI-Pyr14TFSI solid polymer electrolyte exhibited good charge-discharge performance in Li/SPE/LiFePO4 cells at 50℃.
참고문헌 (15)
- J. Kalhoff, "Safer electrolytes for lithium-ion batteries: State of the art and perspectives", ChemSusChem, 8, pp.2154~ (2015)
- 김두환, "에틸렌 카보네이트기를 함유하는 가지형 고체 고분자전해질의 합성 및 물리화학적 특성", 전기화학회지, 18(4), pp.150~155 (2015), 한국전기화학회
- M. Wetjen, "Thermal and electrochemical properties of PEO-LiTFSI-Pyr14TFSI-based composite cathodes, incorporating 4 V-class cathode active materials", J. Power Sources, 246, pp.846~ (2014)
- J. H. Shin, "Characterization of Solvent-Free Polymer Electrolytes Consisting of Ternary PEO-LiTFSIPYR14TFSI", J. Electrochem. Soc, 153, pp.A1649~ (2006)
- G. B. Appetecchi, "Characterization of PEO-based composite cathodes. I. Morphological, thermal, mechanical, and electrical properties", J. Electrochem. Soc, 147, pp.451~ (2000)
- J. K. Kim, "Characterization of N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide-based polymer electrolytes for high safety lithium batteries", J. Power Sources, 224, pp.93~ (2013)
- G. B. Appetecchi, "Effect of the alkyl group on the synthesis and the electrochemical properties of N-alkyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquids", Electrochim. Acta, 54, pp.1325~ (2009)
- P. D. S. Claire, "Degradation of PEO in the solid state: a theoretical kinetic model", Macromolecules, 42, pp.3469~ (2009)
- G. B. Appetecchi, "Hot-pressed, solvent-free, nanocomposite, PEO-based electrolyte membranes: II. All solid-state Li", LiFePO4 polymer batteries, 2003, pp.124, 246~
- 김재광, "Properties of N-butyl-N-methyl-pyrrolidinium bis(trifluoromethanesulfonyl) imide based electrolytes as a function of lithium bis(trifluoromethanesulfonyl) imide doping", 전기화학회지, 14(2), pp.92~97 (2011), 한국전기화학회
- Y. J. Lim, "Ceramic-based composite solid electrolyte for lithium-ion batteries", ChemPlusChem, 80, pp.1100~ (2015)
- P. P. Prosini, "The two-phase battery concept: a new strategy for high performance lithium polymer batteries", J. Power Sources, 786, pp.97~98 (2001)
- S. Matsui, "Liquid-free rechargeable Li polymer battery", J. Power Sources, 97, pp.772~ (2001)
- A. Lahiri, "Characterisation of the solid electrolyte interface during lithiation", delithiation of germanium in an ionic liquid, 2016, pp.18, 5630~
- Y. H. Kim, "Electrochemical properties of PEO-based polymer electrolytes blended with different room temperature ionic liquids", Macromol. Symp, 183, pp.249~250 (2007)