Surface Treatment of LiFePo4 Cathode Material for Lithium Secondary Battery
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In this study, nano-crystallized Al2O3 was coated on the surface of LiFePO4 powders via a novel dry coating method. The influence of coated LiFePO4 upon electrochemical behavior was discussed. Surface morphology characterization was achieved by transmission electron microscopy (TEM), clearly showing nano-crystallized Al2O3 on LiFePO4 surfaces. Furthermore,it revealed that the Al2O3-coated LiFePO4 cathode exhibited a distinct surface morphology. It was also found that the Al2O3 coating reduces capacity fading especially at high charge/discharge rates. Results from the cyclic voltammogram measurements (2.5-4.2 V) showed a significant decrease in both interfacial resistance and cathode polarization. This behavior implies that Al2O3 can prevent structural change of LiFePO4 or reaction with the electrolyte on cycling. In addition, the Al2O3coated LiFePO4 compound showed highly improved area-specific impedance (ASI), an important measure of battery performance. From the correlation between these characteristics of bare and coated LiFePO4, the role of Al2O3 coating played on the electrochemical performance of LiFePO4was probed.
Abstract
In this study, nano-crystallized Al2O3 was coated on the surface of LiFePO4 powders via a novel dry coating method. The influence of coated LiFePO4 upon electrochemical behavior was discussed. Surface morphology characterization was achieved by transmission electron microscopy (TEM), clearly showing nano-crystallized Al2O3 on LiFePO4 surfaces. Furthermore,it revealed that the Al2O3-coated LiFePO4 cathode exhibited a distinct surface morphology. It was also found that the Al2O3 coating reduces capacity fading especially at high charge/discharge rates. Results from the cyclic voltammogram measurements (2.5-4.2 V) showed a significant decrease in both interfacial resistance and cathode polarization. This behavior implies that Al2O3 can prevent structural change of LiFePO4 or reaction with the electrolyte on cycling. In addition, the Al2O3coated LiFePO4 compound showed highly improved area-specific impedance (ASI), an important measure of battery performance. From the correlation between these characteristics of bare and coated LiFePO4, the role of Al2O3 coating played on the electrochemical performance of LiFePO4was probed.
참고문헌 (17)
- A. M. Andersson, "Surface Characterization of Electrodes from High Power Lithium-Ion Batteries", J. Electrochem. Soc., 149, pp.1358~ (2002)
- T. Ohzuku, "Layered Lithium Insertion Material of LiCo1", 3Ni1, 3O2 for Lithium-Ion Batteries, pp.Chem. Lett, 2001[DOI]
- O2 (0 < x < 1, "2)", J. Electrochem. Soc., 149, pp.1332~ (2002)
- Y. Cui, "Enhanced electrochemical properties of LiFePO4 cathode material by CuO and carbon co-coating", Journal of Alloys and Compounds, 490, pp.236~ (2010)
- S. Franger, "Optimized Lithium Iron Phosphate for High-Rate Electrochemical Applications", J. Electrochem. Soc., 151, pp.1024~ (2004)
- J. Barker, "Lithium Iron(II) Phospho-olivines Prepared by a Novel Carbothermal Reduction Method", Electrochem. Solid-State Lett., 6, pp.53~ (2003)
- E. M. Bauer, "Versatile Synthesis of Carbon-Rich LiFePO4 Enhancing Its Electrochemical Properties", Electrochem. Solid-State Lett., 7, pp.85~ (2004)
- P. P. Prosini, "Improved electrochemical performance of a LiFePO4- based composite cathode", Electrochim. Acta., 46, pp.3517~ (2001)
- A. A. Salah, "Reduction Fe3+ of Impurities in LiFePO4 from Pyrolysis of Organic Precursor Used for Carbon Deposition", J. Electrochem. Soc., 153, pp.1692~ (2006)
- Y. G. Wang, "The Design of a LiFePO4", Carbon Nanocomposite With a Core–Shell Structure and Its Synthesis by an In Situ Polymerization Restriction Method, 2008, pp.47, 7641~
- D. Choi, "Surfactant based sol-gel approach to nanostructured LiFePO4 for high rate Li-ion batteries", J. Power Sources, 163, pp.1064~ (2007)
- K. Zaghib, "Surface Effects on the Physical and Electrochemical Properties of Thin LiFePO4 Particles", Chem. Mater., 20, pp.462~ (2008)
- C. Delacourt, "Size Effects on Carbon-Free LiFePO4 Powderse", Electrochem. Solid-State Lett., 9, pp.352~ (2006)
- J. Cho, "Novel LiCoO2 Cathode Material with Al2O3 Coating for a Li Ion Cell", Chem. Mater., 12, pp.3788~ (2000)
- J. T. Son, "Electrochem. Solid-State Lett. submitted.", ~
- S. -W. Oh, "Improvement of electrochemical properties of LiNi0.5Mn1.5O4 spinel material by fluorine substitution", J. Power Sources, 157, pp.464~ (2006)
- I. Belharouak, "Li(Ni1", 3Co1, 3)O2 as a suitable cathode for high power applications, pp.J. Power Sources, 2003[DOI]