전기방사법을 이용한 LiFePO4 양극 활물질의 합성 및 전기화학적 특성
Synthesis and Electrochemical Properties of LiFePO4 Cathode Material obtained by Electrospinning Method
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초록
본 연구에서는 LiFePO4의 입자크기를 조절함으로써 우수한 전극특성을 나타낼 수 있도록 최적의 입자크기(50~100 nm)를 가지는 LiFePO4 양극 활물질을 전기방사법을 이용하여 합성하였다. XRD 분석결과 FeP, Fe2P 등의 불순물이 존재하지 않는 Pnma의 공간군을 가지는 잘 발달된 사방정 구조의 LiFePO4가 합성됨을 확인하였으며, SEM 분석을 통하여 시료의 입자형태 및 크 기를 관찰하였다. 0.1 mA/cm2의 전류밀도와 2.8~4.0 V의 전위영역에서 충·방전 테스트 수행시 135 mAh/g의 초기 방전용량을 나타내었으며, 50 싸이클 후에도 99.9% 이상의 용량 보존율을 보이는 우수한 싸이클 특성을 나타내었다
Abstract
LiFePO4 material was synthesized by electrospinning method to obtain optimal particle size (50~100 nm) without carbon coating or ball milling. This material showed an orthorthombic structure with Pnma space group without any impurities, such as FeP or Fe2P, in the XRD pattern. The particle morphology and particle shape were observed by SEM analysis. Li/LiFePO4 cell showed a high initial discharge capacity of 135 mAh/g, at current density of 0.1 mA/cm2 with a cut-off voltage of 2.8 to 4.0V. This cell exhibited a perfect cycle performance over 99.9% cycle retention rate up to 50 cycles
참고문헌 (18)
- A. K. Padhi, "'Phospho-olivines as Positive-Electrode Materials for Rechargeable Lithium Batteries'", J.Electrochem. Soc, 144, pp.1188~ (1997)
- T. Ohzuku, "'Comparative Study of LiCoO2, LiNi1", 2Co1, Electrochim. Acta, pp.1993, 38[DOI]
- K. Striebel, "'The Development of LOw Cost LiFePO4-based High Power Lithium-ion Batteries'", J. Power Sources, 146, pp.33~ (2005)
- N. Ravet, "'Electroactivity of Natural and Synthetic Triphylite'", J. Power Sources, 97, pp.503~ (2001)
- P. P. Prosini, "'Determination of the Chemical Diffusion Coefficient of Lithium in LiFePO4'", Solid State Ionics, 148, pp.45~ (2002)
- A. S. Andersson, "'Lithium Extraction", Insertion in LiFePO4 : an X-ray Diffraction and Mössbauer Spectroscopy Study', 2000, pp.130, 41~
- M. Gaberscek, "'PoRous, Carbon-decorated LiFePo4 Prepared by Sol-gel Method Based on Citric Acid'", Solid-State Ionics, 176, pp.1801~ (2005)
- C. Delacourt, "'Size Effects on Carbon-Free LiFePO4 Powders The Key to Superior Energy Density'", Electrochem. Solid-State Lett, 9, pp.A352~ (2006)
- H. Huang, "Approaching Theoretical Capacity of LiFePO4 at Room Temperature at High Rates’", Electrochem. Solid-State Lett, 4, pp.A170~ (2001)
- S. Yang, "'Reactivity, Stability and Electrochemical Behavior of Lithium Iron Phosphates'", Electrochem. Commun, 4, pp.239~ (2002)
- F. Croce, "'A Novel Concept for the Synthesis of an Improved LiFePO4 Lithium Battery Cathode'", Electrochem. Solid-State Lett, 5, pp.A47~ (2002)
- R. Dominko, "'Impact of the Carbon Coating Thickness on the Electrochemical Performance of LiFePO4", C Composites', 2005, pp.152, A607~
- A. D. Spong, "'A Solution-Precursor Synthesis of Carbon-Coated LiFePO4 for Li-Ion Cells'", J. Electrochem. Soc, 152, pp.A2376~ (2005)
- G. X. Wang, "'Characterization of LiMxFe1-xPO4 (M=Mg, Zr, Ti) Cathode Materials Prepared by the Sol-Gel Method", Electrochem. Solid-State Lett, 7, pp.A503~ (2002)
- D. Choi, "'Surfactant bAsed Sol–gel Approach To Nanostructured Lifepo4 For High Rate Li-ion Batteries'", J. Power Sources, 163, pp.1064~ (2007)
- N. Yu, "Nanofibers of LiMn2O4 by electrospinning'", J. Colloid and Interface Science, 285, pp.163~ (2005)
- C. Shao, "'Preparation of LiCoO2 Nanofibers by Electronning Technique'", J. Physics and Chemistry of Solids, 67, pp.1423~ (2006)
- A. S. Andersson, "'The Source Of Firstcycle Capacity Loss in LiFePO4'", J. Power Sources, 97, pp.498~ (2001)