BF3LiMA기반 자기-도핑형 겔 고분자 전해질의 전기화학적 특성에 미치는 리튬이온 농도의 영향
Effect of Lithium Ion Concentration on Electrochemical Properties of BF3LiMA-based Self-doping Gel Polymer Electrolytes
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초록
전해액 상용성의 boron trifluoride lithium methacrylate (BF3LiMA)를 기본으로 하는 겔 고분자전해질 (gel polymer electrolytes, GPE)에서 BF3LiMA의 농도가 이온전도도, 전기화학적 안정성에미치는 영향을 AC impedance 측정법과 linear sweep voltammetry (LSV)를 통하여 평가하였다. 그 결과 BF3LiMA가 4wt% (고분자함량 21 wt%)일 때, 상온 이온전도도가 5.3 × 10−4S cm−1로서가장 높게 관찰되었으며 4 wt% 전후로 다시 감소하였다. BF3LiMA 기반의 GPE는 음이온이 고정되어 있는 자기-도핑형 계열로서 우수한 전기화학적 안정성을 확인하였다. 한편 BF3LiMA 기반GPE는 리튬금속과 비교적 불안정한 계면반응성을 보여주었지만 흑연/GPE/흑연, LCO/GPE/LCO 에서는 높은 계면안정성을 형성하였다. 따라서 BF3LiMA 기반의 GPE를 통하여 높은 상온 이온전도도와 전기화학적 안정성 및 흑연과 LCO 양극산화물에 대한 우수한 계면특성을 확보할 수 있었다.
Abstract
Boron trifluoride lithium methacrylate (BF3LiMA)-based gel polymer electrolytes (GPEs) were synthesized with various BF3LiMA concentration to elucidate the effect on ionic conductivity and electrochemical stability by a AC impedance and linear sweep voltammetry (LSV). As a result, the highest ionic conductivity reached 5.3 × 10−4 S cm−1 at 25˚C was obtained for 4 wt% of BF3LiMA. Furthermore, high electrochemical stability up to 4.3 V of the BF3LiMA-based GPE was observed in LSV measurement since the counter anion was immobilized in this self-doped system. On the other hand, it was assumed that there was a rapid decomposition of electrolytes on a lithium metal electrode which results in a high solid electrolyte interface (SEI) resistance. However, a high stability toward graphite or lithium cobalt oxide (LCO)electrode thereby a low SEI resistance was observed from the AC impedance measurement as a function of storage time at 25˚C. Consequently, the high ionic conductivity, good electrochemical stability and the good interfacial compatibility with graphite and LCO were achieved in BF3LiMA-based GPE.
참고문헌 (18)
- D. Sadoway, "Self-doped block copolymer electrolytes for solid-state rechargeable lithium batteries", J. Power Sources, 97, pp.621~ (2001)
- H. Xie, "Synthesis and properties of ionic conducting crosslinked polymer and copolymer based on dimethacryloyl poly(ethylene glycol)", European Polymer Journal, 37, pp.1997~ (2001)
- Y. Lee, "Electrochemical characteristics of polymer electrolytes based on P(VdF-co-HFP)", PMMA ionomer blend for PLIB, 2001, pp.97, 616~
- S. Zhang, "Single-ion conductivity and carrier generation of polyelectrolytes", Solid State Ionics, 76, pp.121~ (1995)
- J. Cowie, "Novel single ion, comb-branched polymer electrolytes", Solid State Ionics, 123, pp.233~ (1999)
- X. Sun, "New single ion conductors (“polyBOP” and analogs) for rechargeable lithium batteries", Solid State Ionics, 175, pp.743~ (2004)
- H. Allcock, "Single ion conductors-polyphosphazenes with sulfonimide functional groups", Solid State Ionics, 177, pp.741~ (2006)
- N. Byrne, "Composition effects on ion transport in a polyelectrolyte gel with the addition of ion dissociators", Electrochimica Acta, 50, pp.3917~ (2005)
- X. Sun, "Comb-shaped single ion conductors based on polyacrylate ethers and lithium alkyl sulfonate", Electrochimica Acta, 50, pp.1139~ (2005)
- M. Watanabe, "Anionic effect on ion transport properties in network polyether electrolytes", Electrochimica Acta, 46, pp.1487~ (2001)
- Z. Florjanczyk, "Lithium gel polyelectrolytes based on crosslinked maleic anhydride-styrene copolymer", Electrochimica Acta, 44, pp.3563~ (2000)
- S. Ryu, "Effect of counter ion placement on condutcitity in single-ion conducting block copolymer electrolytes", J. Electrochem. Soc., 152(1), pp.158~ (2005)
- M. Watanabe, "Single ion conduction in polyether electrolytes alloyed with lithium salt of a perfluorinated polyimide", Electrochimica Acta, 45, pp.1187~ (2000)
- N. Choi, "Nanocomposite single ion conductor based on organic-inorganic hybrid", Solid State Ionics, 167, pp.293~ (2004)
- W. Kang, "Synthesis and electrochemical properties of lithium methacrylate-based self-doped gel polymer electrolytes", Electrochimica Acta, 54, pp.4540~ (2009)
- D. Kim, "Electrical properties of the plasticized plymer electrolytes based on acrylonitrilemethyl methacrylate copolymers", Solid State Ionics, 106, pp.329~ (1998)
- D. Vieira, "Conductivity study of a gelatin-based polymer electrolyte", Electrochimica Acta, 53, pp.1404~ (2007)
- J. MacCallum, "Polymer Electrolyte Reviews-1", pp.69~ (1987), Elsevier Applied Science