전기화학회지 (Journal of the Korean Electrochemical Society)

  • 제10권4호
  • /
  • Pages.239-244
  • /
  • 2007
  • /
  • 1229-1935(pISSN)
  • /
  • 2288-9000(eISSN)
한국전기화학회 (The Korean Electrochemical Society)
권호 표지
DOI QR코드

DOI QR Code

음이온 치환을 이용한 Li1-xFeO2-yFy-LixMnO2 (Mn/(Mn + Fe) = 0.8, 0≤y≤0.15) 양극 활물질의 합성 및 전기화학적 특성

Synthesis and Electrochemical Properties of Li1-xFeO2-yFy-LixMnO2 (Mn/(Mn + Fe) = 0.8, 0≤y≤0.15)) Cathode Materials by Anion Substitution

  • 허정배 (전남대학교 응용화학공학부, 기능성 나노 신화학소재 사업단) ;
  • 박금재 (전남대학교 응용화학공학부, 기능성 나노 신화학소재 사업단) ;
  • 이윤성 (전남대학교 응용화학공학부, 기능성 나노 신화학소재 사업단)
  • Heo, J.B. (Faculty of Applied Chemical Engineering, Center for Functional Nano Fine Chemicals, Chonnam National University) ;
  • Park, G.J. (Faculty of Applied Chemical Engineering, Center for Functional Nano Fine Chemicals, Chonnam National University) ;
  • Lee, Y.S. (Faculty of Applied Chemical Engineering, Center for Functional Nano Fine Chemicals, Chonnam National University)
  • 발행 : 2007.11.28
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

산소자리에 치환된 불소가 $Li_{1-x}FeO_2Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8) 양극 활물질에 미치는 영향을 고찰하기 위해 다양한 양의 불소를 치환시킨 $Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8, $0.05{\le}y{\le}0.15$) 양극 활물질을 고상법을 이용하여 합성하였다. 불소 미치환 시료 및 치환양이 0.05와 0.1의 시료의 경우, $1-1.5\;{\mu}m$ 크기의 막대 형상 분말 형태에 50-100 nm정도의 작은 구형 입자들이 주위에 분포되어 있는 형태이었다. 반면, 불소 치환양이 0.15인 시료의 경우, 그 모양이 구형으로 변화되어지며 입자가 급격하게 성장하였다. 합성된 시료를 이용하여 제작된 셀들의 충 방전 수행 결과, $Li/Li_{1-x}FeO_{1.9}F_{0.1}-Li_xMnO_2$ 셀이 163 mAh/g의 가장 높은 초기용량을 보였으며 50 싸이클 후에도 95%의 높은 가역 특성을 보였다. 특히, 활물질내의 불소 치환양이 증가할수록 초기 방전용량도 같이 증가하였으나, 불소이온의 치환양이 일정량을 (y>0.1) 넘는 경우에는 산소 자리에 불소이온이 완전하게 치환되지 못하고 불순물로 존재함으로써 전지의 가역특성을 현저하게 저하시키는 요인으로 작용함을 확인하였다.

In order to investigate the effect of fluorine ion in the $Li_{1-x}FeO_2Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8) cathode material, it was synthesized $Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8, $0.05{\le}y{\le}0.15$) cathode materials at $350^{\circ}C$ for 10hrs using solid-state method. $Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ (Mn/(Mn + Fe) = 0.8, $0.0{\le}y{\le}0.1$ was composed many large needle-like particles of about $1-1.5\;{\mu}m$ and small particles of about 50-100 nm, which were distributed among the larger particles. However, $Li_{1-x}FeO_{1.85}F_{0.15}-Li_xMnO_2$ material showed slightly different particle morphology. The particles of $Li_{1-x}FeO_{1.85}F_{0.15}-Li_xMnO_2$ were suddenly increased and started to be a spherical type of particle shape. $Li/Li_{1-x}FeO_{1.9}F_{0.1}-Li_xMnO_2$ cell showed a high initial discharge capacity of 163 mAh/g and a high cycle retention rate of 95% after 50 cycles. The initial discharge capacity of $Li/Li_{1-x}FeO_{2-y}F_y-Li_xMnO_2$ ($0.05{\le}y{\le}0.15$) cells increased according to the increase of F content. However, the cycleability of this cell was very rapidly decreased when the substituted fluorine content is over 0.1. We suggested that too large amount of F ion fail to substitute into the $Li_{1-x}FeO_2-Li_xMnO_2$ structure, which resulted in the severe decline of battery performance.

키워드

참고문헌

  1. K. Mizushima, P. C. Jones, P. J. Wiseman, and J. B. Goodenough, '$Li_xCoO_2$ (0 https://doi.org/10.1016/0025-5408(80)90012-4
  2. J. N. Reimers, and J.R. Dahn, 'Electrochemical and In Situ X-Ray Diffraction Studies of Lithium Intercalation in $Li_xCoO_2$', J. Electrochem. Soc, 139, 2091, 62 (1992) https://doi.org/10.1149/1.2069499
  3. Tsutomu Ohzuku, Atsushi Ueda, Masatoshi Nagayama, Yasunobu Iwakoshi, and Hideki Komori, 'Comparative study of $LiCoO_2$, $LiNi_{1/2}Co_{1/2}O_2$ and $LiNiO_2$ for 4 volt secondary lithium cells', Electrochimica Acta, 38, 1159 (1993) https://doi.org/10.1016/0013-4686(93)80046-3
  4. G G Amatucci, J.M. Tarascon, and L.C. Klein 'Cobalt dissolution in $LiCoO_2-based$ non-aqueous rechargeable batteries', Solid state Ionics, 83, 167 (1996) https://doi.org/10.1016/0167-2738(95)00231-6
  5. J. C. Anderson and M. Schieber, 'Order-disorder transitions in heat-treated rock-salt Lithium Ferrite' J. Phys. Chem. Solids, 25, 961 (1962) https://doi.org/10.1016/0022-3697(64)90033-2
  6. Y. Sakurai, H. Arai, and J. Yamaki, 'Preparation of electrochemically active ${\alpha}-LiFeO_2$ at low temperature', Solid State Ionics, 113-115, 29 (1998)
  7. C. Barriga, V. Barron, R. Gancedo, M. Gracia, J. Morales, J.L. Tirado and J. Torrent, 'Lithium ferrite formation by precipitation from Fe(ni) solutions', Solid State Chem, 77, 132 (1988) https://doi.org/10.1016/0022-4596(88)90100-4
  8. J. C. Anderson, S. K. Dey, and V. Halpen, 'The magnetic susceptibilities of $LiFeO_2$', J. Phys. Chem. solids, 26, 1555 (1965) https://doi.org/10.1016/0022-3697(65)90056-9
  9. R. Kanno, T. Shirane, Y Kawamoto, Y. Takeda, M. Takano, M. Ohashi, and Y Yamaguchi, 'Synthesis, Structure, and Electrochemical Properties of a New Lithium Iron Oxide, $LiFeO_2$, with a Corrugated Layer Structure', J. Electrochem. Soc, 143, 2435 (1996)
  10. Y. Sakurai, H. Arai, S. Okada, and J. Yamaki, 'Low temperature synthesis and electrochemical characteristics of $LiFeO_2$cathodes', J. Power Sources, 68, 711 (1997) https://doi.org/10.1016/S0378-7753(96)02579-7
  11. Y. S. Lee, C. S. Yoon, Y K. Sun, K. Kobayakawa, and Y. Sato, 'Synthesis of nano-crystalline $LiFeO_2$ material with advanced battery performance', Electrochem. commun., 4, 727 (2002) https://doi.org/10.1016/S1388-2481(02)00436-8
  12. T. Matsumura, R. Kanno, Y. Inaba, Y. Kawamoto, and M. Takano, 'Synthesis, Structure, and Electrochemical Properties of a New Cathode Material, $LiFeO_2$, with a Tunnel Structure', J. Electrochem. Soc., 149, 1509 (2002) https://doi.org/10.1149/1.1516769
  13. Y. S. Lee, S. Sato, Y. K. Sun, K. Kobayakawa, and Y. Sato, 'Preparation of Mn-substituted $LiFeO_2$ : A solid solution of $LiFeO_2$ and $Li_xMnO_2$', Electrochem. Commun., 5, 359 (2003) https://doi.org/10.1016/S1388-2481(03)00067-5
  14. G. J. Park, Y S. Lee, K. S. Nahm, and Y. Sato, 'Synthesis and Electrochemical Properties of $Li_{1-x}Fe_{0.8}Ni_{0.2}O_2-Li_xMnO_2$ (Mn/ (Fe + Ni + Mn) = 0.8) Material', J. Power Sources in Press
  15. Y.-J. Kang, J.-H. Kim and Y.-K. Sun, 'Structural and electrochemical study of Li-Al-Mn-O-F spinel material for lithium secondary batteries', J. Power Sources, 146, 237 (2005) https://doi.org/10.1016/j.jpowsour.2005.03.037
  16. Yun-Sung Lee, Sung-Jun Cho, and Masaki Yoshio, 'Preparation and Electrochemical Properties of $Li_{1.1}Mn_2O_{3.9}F_{0.1}$ Material for Lithium Secondary Battery', Korean Journal of Chemical Engineering, 23(4), 566 (2006) https://doi.org/10.1007/BF02706795
  17. G. G. Amatucci, N. Pereira, T. Zheng, and J.M. Tarascon, 'Failure Mechanism and Improvement of the Elevated Temperature Cycling of $LiMn_2O_4$ Compounds Through the Use of the $LiAl_xMn_{2-x}O_{4-z}F_z$ Solid Solution', J. Electrochem. Soc., 148, A171 (2001) https://doi.org/10.1149/1.1342168