濕氏化學法由於具有成本低、簡單的製作流程和容易控制化學計量比與顯微結構的優點，因此被廣泛用於製造薄膜與研究。然而，薄膜的品質高度依賴於前驅物溶液的性質。在本研究中，幾丁聚醣用作前驅物溶液的螯合劑，因Li/ Co離子能與幾丁聚醣產生螯合作用，使前驅物溶液可以均勻分散。利用此前驅物溶液可以有效的沉積鋰鈷氧化物薄膜。由循環伏安與充放電的測試，以此溶膠凝膠的前驅物溶液所製備的鋰鈷氧化物薄膜可具有初次放電電容量達129mAh/g。 以同樣的方式亦可於可撓曲的不銹鋼基材上沉積LiCoO2陰極。經500°C的熱處理，X光繞射結果顯示，LiCoO2前驅物可獲得層狀結構，然而當退火溫度高於600°C時，不銹鋼基材將會被氧化，並進一步與LiCoO2反應。此外，循環伏安與充放電的測試顯示該製程條件下的LiCoO2具有電化學的特性，於600℃退火熱處理的LiCoO2薄膜的電化學性能在不同溫度下得到的薄膜相比，具有更好的循環特性。具有奈米板形狀的LiCoO2可以就由水熱法的方式獲得。經水熱法的製程可獲得六方晶的LiCoO2與立方晶的Co3O4兩相薄膜，其兩相形成主導因素為pH值的控制。另外，循環伏安與充放電的測試顯示，以此方法所製備的LiCoO2薄膜亦具有被用作鋰離子電池陰極材料的電化學可逆性與性質。

Wet chemical method is one of the methods which were widely used to fabricate thin films, due to low cost, simple processing and easy to control the composition stoichiometry and desired microstructure. However, the quality of the deposited thin films was highly dependent on the nature of precursor solution. In this study, the addition of chitosan in the precursor solution was found to be an effective method for the deposition of LiCoO2 thin films. Due to the chemical bonding between chitosan and cations, Li/Co ions can be homogeneously distributed in the precursor solution at a molecular scale. Such a precursor solution is beneficial for the deposition of a single-phase LiCoO2 film on a Pt-coated silicon substrate. The CV and charge–discharge test also showed that the prepared thin film cathode deposited from the chitosan-added precursor solution exhibited initial discharge capacity of 129 mAh g−1. Thus, the lithium/ cobalt acetates-containing precursor solution with chitosan addition is a unique and appropriate way to prepare a dense and single-phase LiCoO2 film. By the same process, the LiCoO2 cathode can be deposited on a flexible stainless steel. After annealing at ca. 500°C, the results of XRD showed that the LiCoO2 gel was crystallized in a layered structure. When the annealing temperatures were kept at 700°C, the stainless steel substrate was oxidized and reacted with LiCoO2. The structure of LiCoO2 was no longer observed. The SEM observation indicated that the average grain size of films increased with increasing temperature. The thickness of spin-coated films is ca. 1–3 μm. Also, the CV measurement showed that the LiCoO2 film exhibited a good electrochemical reversibility to be used as cathode material. Compared to the electrochemical properties of the films obtained at various temperatures, the 600°C-annealed LiCoO2 film exhibits a better cycle retention than 500°C-annealed LiCoO2 film. Nanosheet LiCoO2 can be obtained by hydrothermal process at a low temperature. After hydrothermal process, the XRD results indicate that the LiCoO2 and Co3O4 phase formed and crystallized in hexagonal and cubic structure respectively and the pH value was the key factor that dominates the phase purity and crystal shape. Also, the CV measurement and charge-discharge test showed that the LiCoO2 film exhibited electrochemical reversibility to be used as cathode material for Li-ion battery.

1. J.-M. Tarascon and M. A. Armand, “Issues and challenges facing rechargeable lithium batteries”, Nature, 414, p.359 (2001)
2. J. Hajek, French Patent, 8, 10 (1949)
3. M. S. Whittingham, “Electrochemical energy storage and intercalation chemistry”, Science, 192, p.1226 (1976).
4. M. S. Whittingham, Chalcogenide battery, US Patent 4009052
5 . “Battery Recall Update”, Adv. Batt. Technol., 25, p.4 (1989)
6. R. Kanno, Y. Takeda, T. Ichikawa, K. Nakanishi and O. Yamamoto, “Carbon as negative Electrodes in Lithium Secondary Cells”, J. Power Sources, 26, p.535 (1989)
7. J. O. Besenhard, M. Hess and P. Komeda, “Dimensionally stable Li-alloy electrodes for secondary batteries”, Solid State Ionics, 40-41, p.525 (1990)
8. M. Lazzari and B. Scrosati, “A Cyclable Lithium Organic Electrolyte Cell Based on Two Intercalation Electrodes”, J. Electrochem. Soc., 127, p.733 (1980)
9. T. Nagaura, and K. Tozawa, “Lithium ion rechargeable battery”, Prog. Batteries Solar Cells, 9, p.209 (1990)
10. P. Poizot, S. Laruelle, S. Grugeon, L. Dupont, and J.-M. Tarascon, “Nano-sized transition metal oxides as negative electrode material for lithium-ion batteries”, Nature, 407, p. 496 (2000)
11. C. L. Liao, Y. H. Lee, S. T. Chang and K. Z. Fung, “Structural Characterization and Electrochemical Properties of RF-Sputtered Nanocrystalline Co3O4 Thin-Film Anode”, J. Power Sources, in press
12. Y. H. Lee, I. C. Leu, S. T. Chang, C. L. Liao, K. Z. Fung, “The electrochemical capacities and cycle retention of electrochemically deposited Cu2O thin film toward lithium”, Electrochimica Acta, 50, p.551 (2004)
13. Y. H. Lee, I. C. Leu, C. L. Liao, S. T. Chang, M. T. Wu, J. H. Yen, and K. Z. Fung, “Fabrication and Characterization of Cu2O Nanorod Arrays and Their Electrochemical Performance in Li-Ion Batteries”, Electrochemical and Solid-State Letters, 9, p.A207 (2006)
14. E. Zhecheva, R. Stoyanova, G. Tyuliev, K. Tenchev, M. Mladenov, S. Vassilev, “Surface interaction of LiNi0.8Co0.2O2 cathodes with MgO”, Solid State Sciences, 5, p.711 (2003)
15. H. Zhao, L. Gao, W. Qiu, X. Zhang, “Improvement of electrochemical stability of LiCoO2 cathode by a nano-crystalline coating”, Journal of Power S ources, 132, p.195, (2004)
16. H. Liu, Z. Zhang, Z. Gong, Y. Yang, “A comparative study of LiNi0.8Co0.2O2 cathode materials modifiedby lattice-doping and surface-coating”, Solid State Ionics, 166, p.317 (2004)
17. L. J. Fu, H. Liu, C. Li, Y. P. Wu, E. Rahm, R. Holze, H. Q. Wu, “Surface modifications of electrode materials for lithium ion batteries”, Solid State Sciences, 8, p.113 (2006)
18. K. Kanehori, K. Matsumoto, K. Miyauchi; T. Kudo, “Thin film solid electrolyte and its application to secondary lithium cell”, Solid State Ionics, 9-10, p 1445 (1983)
19. J. B. Bates, D. R. Gruzalski, C. F. Luck, “ Rechargeable solid state lithium microbatteries”, IEEE Micro Electro Mechanical Systems, 7-10, p.82 (1993)
20. R. B. Goldner, S. Slaven, T. Y. Liu, T. E. Haas, F. O. Arntz, P. Zerigian, “Properties of a carbon negative electrode in completely inorganic thin film Li-ion batteries with a LiCoO2 positive electrode”, Materials Research Society Symposium-Proceedings, v.369, Solid State Ionics IV, p.137 (1995)
21. J. B. Bates and N. J. Dudney , “Thin Film Rechargeable Lithium Batteries for Implantable Devices” , American Society for Artificial Internal Organs Inc., 43 , p.M644 (1997)
22. 盧俊安、林鴻欽、邱國展, “從Orgainc Electronic Conference 2007　觀察軟性電子未來之發展趨勢”, 工業材料, 252, p.80 (2007)
23. http://www.materialsnet.com.tw/DocView.aspx?id=7325
24. 林美雲譯, “使用LiMn2O4系正極材料的鋰離子二次電池”, 工業材料, 145, p.116 (1999)
25. 洪逸明, “鋰離子二次電池陰極材料LiMn2O4±δ之合成及其電化學性質”, 國立成功大學材料科學及工程研究所博士論文, p.16-24 (2001)
26. K. Mizushima, P. C. Jones, P. J. Wiseman and J. B. Goodenough, “LixCoO2 (0  x  1): a new cathode material for batteries of high energy density”, Solid State Ionics, 3/4, p 171 (1980)
27. R. J. Gummow, M. M. Thackery, W. I. F. David and S. Won, “LixCoO2 (0  x  1): a new cathode material for batteries of high energy density”, Mat. Res. Bull., 15, p.783 (1980)
28. E. Rossen, J.N. Reimers, and J.R. Dahn, “Synthesis and electrochemistry of spinel LT-LiCoO2”, Solid State Ionics, 62, p.53 (1993)
29. B. Garcia, J. Farcy, J. P. Pereira-Ramos, J. Perichon, N. Baffier, “Low-temperature cobalt oxide as rechargeable cathodic material for lithium batteries”, J. Power Sources, 54, p.373 (1995)
30. T. Ohzuku, H. Konori, K. Sawai, and T. Hirai, “Natural graphite as an anode for rechargeable nonaqueous cells”, Chem. Express, 5, p.733 (1990)
31. R. J. Gummow, M. M. Thackeray, W. I. F. David and S. Hull, “Structure and electrochemistry of lithium cobalt oxide synthesized at 400℃” Mat. Res. Bull., 27, p.327 (1992)
32. M. Yoshio, Y. Todorov, K. Yamato, H. Noguchi, J. I. Itoh, M. Okada and T. Mouri, “Preparation of LiyNi1-xMnxO2 as a cathode for lithium-ion battery”, J. Power Sources, 74, p.46 (1998)
33. C. Delmas, Mater. Sci. Eng., B3, p.97 (1980)
34. L. P. L. M. Rabou and A. Roskam, “Cycle-life improvement of Li/LiCoO2 batteries”, J. Power Sources 54, p.316 (1995)
35. H. Stephen, T. Stephen, Solubilities of Inorganic and Organic
Compounds, Pergamon Press, New York, 1963.
36. A. K. Padhi, K. S. Nanjundaswamy, and J. B. Goodenough, J. Electrochem. Soc., 144(4), p.1188 (1997).
37. A. K. Paclhi, K. S. Nanjunclaswamy, C. Masquelier, S. Okada, and J. B. Goodenough, J. Electrochem.Soc., 144(5), p.1609 (1997).
38. A. K. Padhi, K. S. Nanjundaswamy, C. Masquelier, and J. B. Goodenough, J. Electrocheni. Soc., 144(8), p.2581 (1997).
39. E.-H. M. Diefallah, “ Kinetic analysis of Thermal Decomposition
Reactions. Part VI. Thermal Decomposition of Manganese(II) Acetate
Tetrahydrate＂, Thermochimica Acta 202 p.1 (1992).
40. M.A. Mohamed, S.A. Halawy,“Kinetic and Mechanistic Study of the
Non-Isothermal Decomposition of Manganese(II) acetate tetrahydrate＂,
Thermochimica Acta 242 p.173 (1994).
41. G.E. Tobon-Zapata, E.G. Ferrer, S.B. Etcheverry, E.J. Baran,“Thermal
Behaviour of Pharmacologically Active Lithium Compounds＂, Journal
of Thermal Analysis and Calorimetry 61 p.29 (2000).
42. F. Yao, W. Chen, H. Wang, H. Liu, K. Yao, P. Sun, H. Lin,“A Study on Cytocompatible Poly(chitosan-g-l-lactic acid) ＂ , Polymer 44 p.6435 (2003).
43. C. Zhang, Q. Ping, H. Zhang, J. Shen,“Synthesis and Characterization
of Water-Soluble O-Succinyl-Chitosan＂, European Polymer Journal 39,
p.1629 (2003).
42. S.J. Kim, S.R. Shin, Y.M. Lee, S.I. Kim,“Swelling Characterizations of
Chitosan and Polyacrylonitrile Semi-Interpenetrating Polymer Network
Hydrogels＂, Journal of Applied Polymer Science 87, p.2011 (2003).
44. J. N. Reimers, J. R. Dalin, “Electrochemical and In Situ X-ray diffraction studies of lithium intercalation in LiCoO2”, J. Electrochem. Soc., 139, p.2091 (1992)
45. M.S. Yazici, D. Krassowski, J. Prakash, “Flexible graphite as battery anode and current collector”, Journal of Power Sources, 141, 171–176(2005)
46. Ki Tae Nam, Dong-Wan Kim, Pil J. Yoo, Chung-Yi Chiang, Nonglak Meethong, Paula T. Hammond, Yet-Ming Chiang, Angela M. Belcher“Virus-Enabled Synthesis and Assembly of Nanowires for Lithium Ion Battery Electrodes”, SCIENCE, 312, p.12 (2006)
47. Shu Saeki, Jaeryeong Lee, Qiwu Zhang, Fumio Saito“Co-grinding LiCoO2 with PVC and water leaching of metal chlorides formed in ground product”, International Journal of Mineral Processing, 74, p.373-378 (2002)