由於磷酸鋰鐵 (LiFePO4, LFP) 汙染低、成本低、熱穩定性高、循環壽命長、可耐大電流放電等優點，使其為前景最看好的陰極材料之一。本論文是以固相法制備LFP正極材料，利用濕式研磨來降低LFP顆粒大小，再利用噴霧乾燥來進行碳塗佈二次造粒，來探討經過噴霧乾燥對磷酸鋰鐵正極複合材料 (LFP/C) 之影響。
將所製備好的LFP/C經由XRD, SEM, DLS, BET, Raman and EA來檢測分析。經由XRD分析顯示，所製備的正極材料為橄欖石結構，具有高結晶性且不含雜相。而EA的量測，碳含量都維持在6-7%的範圍內，並不會隨著噴霧參數而有太大之變化。Raman的部份，不同的噴霧參數變換對於石墨化程度及磷酸根包覆性是有顯著的差異。並且將LFP/C以低密度充放電及高密度充放電來量測電池之性能，經過充放電的分析後，其克電容量在0.1C下有140mAh/g，10C部分還可達到69.84mAh/g。由此可知，經由噴霧乾燥過後，對於LFP/C正極複合材料性能有相當明顯的提升。

Lithium iron phosphate (LiFePO4, LFP) is a promising alternative cathode material because of its low material cost, environmental friendliness, superior thermal safety, and long operational life. In this study, LFP cathode materials were prepared by solid-state method combined with the wet grinding process to reduce the particle size. Then, the thin carbon film was subsequently coated on the surface of LFP particles by using the spray drying and annealing treatment. The effects of spray drying on the electrochemical properties of lithium iron phosphate/carbon (LFP/C) composites were also investigated.
The prepared LFP/C cathode composites were characterized by XRD, SEM, DLS, BET, Raman and EA analysis. XRD analysis indicates the prepared cathode materials with the olive-type phase have a high crystallinity and no impurity phase is observed. EA analysis shows that the carbon content of LFP/C is in the range of 6-7% that is independent of spray drying operation. Raman analysis illustrates that the operating condition of spray drying has an obvious influence on the extent of carbon graphitization and coverage on the LFP surface. Moreover, the charging/discharging analysis shows that the prepared LFP/C composites exhibit high capacity of 140mAh/g at 0.1C and 69.84mAh/g at 10C, respectively. The results shows that performance of LFP/C composites as the cathode materials can be significantly improved by using the spray drying.

明志科技大學碩士學位論文指導教授推薦書 i
明志科技大學碩士學位論文口試委員審定書 ii
明志科技大學學位論文授權書 iii
誌謝 iv
摘要 v
Abstract vi
目錄 vii
表目錄 xi
圖目錄 xiv
第一章 緒論 1
1.1前言 1
1.2鋰離子電池簡介 2
1.3研究動機 6
第二章 文獻回顧 7
2.1鋰離子電池的工作原理 7
2.2磷酸鋰鐵陰極材料的介紹 8
2.3磷酸鋰鐵 (LiFePO4) 充放電描述 11
2.4磷酸鋰鐵 (LiFePO4) 陰極材料合成方法 13
2.4.1噴霧乾燥法 (Spray Drying Method) 14
2.4.2固態反應法 (Solid-State Reaction Method) 18
2.4.3碳熱還原法 (Carbon-Thermal Method) 19
2.4.4微波加熱法 (Microwave Heating Method) 21
2.4.5水熱法 (Hydrothermal Method) 24
2.4.6共沉澱法 (Precipitation Method) 26
2.4.7溶膠凝膠法 (Sol-Gel Method) 27
2.4.8噴霧熱裂解法 (Spray Pyrolysis Method) 28
2.5磷酸鋰鐵材料的改質 29
2.5.1改變LiFePO4粒徑大小 29
2.5.2摻雜不同的金屬改質 (Doping) 30
2.5.3添加高導電性塗佈層 31
2.5.3.1碳修飾 (Carbon Coating) 31
2.5.3.2添加金屬粒子與金屬氧化物 33
第三章 實驗方法 35
3.1 實驗藥品 35
3.2 儀器設備與器材 36
3.3實驗步驟 38
3.3.1以固相法製備磷酸鋰鐵陰極材料 38
3.3.2以噴霧乾燥進行碳塗佈來製備LiFePO4/C正極複合材料 39
3.4材料鑑定分析 41
3.4.1物理性質之分析 42
3.4.1.1表面型態分析-掃描式電子顯微鏡(SEM) 42
3.4.1.2粉末尺寸大小-雷射粒徑分析儀 (DLS) 42
3.4.1.3 XRD 結構分析-X-ray繞射分析儀 43
3.4.1.4包覆碳材結構分析-顯微拉曼光譜儀(Raman) 43
3.4.1.5比表面積分析儀(BET) 44
3.4.2化學性質分析 45
3.4.2.1碳含量分析-元素分析儀(EA) 45
3.4.3電化學性質分析 46
3.4.3.1電池性能測試 46
3.4.3.2界面阻抗分析 (AC) 47
3.4.3.3循環伏安分析 (CV) 47
第四章 結果與討論 48
4.1 LiFePO4正極材料鑑定分析 49
4.1.1 LiFePO4正極材料X光繞射分析 49
4.1.2 LiFePO4正極材料拉曼光譜鑑定 50
4.1.3 SEM與粉體粒徑分析 (DLS) 來觀察粉體型態與粒徑大小 52
4.1.4 LiFePO4正極材料電性分析 54
4.2噴霧乾燥參數變化對LiFePO4/C之影響 57
4.2.1不同氣體流速對LiFePO4/C之影響 57
4.2.1.1不同氣體流速的掃描式電子顯微鏡分析 57
4.2.1.2不同氣體流速的碳元素、比表面積及粒徑分析量測 60
4.2.1.3不同氣體流速的拉曼光譜儀分析 61
4.2.1.4不同氣體流速電性分析比較 64
4.2.2不同固成分對LiFePO4/C之影響 80
4.2.2.1不同固成分的掃描式電子顯微鏡分析 80
4.2.2.2不同固成分的碳元素、比表面積及粒徑分析量測 81
4.2.2.3不同固成分的拉曼光譜儀分析 83
4.2.2.4不同固成分電性分析比較 85
4.2.3不同進料量對LiFePO4/C之影響 98
4.2.3.1不同進料量的掃描式電子顯微鏡分析 98
4.2.3.2不同進料量的碳元素、比表面積及粒徑分析量測 99
4.2.3.3不同進料量的拉曼光譜儀分析 101
4.2.3.4不同進料量電性分析比較 103
4.2.4不同溫度對LiFePO4/C之影響 113
4.2.4.1不同溫度的掃描式電子顯微鏡分析 113
4.2.4.2不同溫度的碳元素、比表面積及粒徑分析量測 114
4.2.4.3不同溫度的拉曼光譜儀分析 116
4.2.4.4不同溫度電性分析比較 118
4.3交流阻抗分析 128
4.4 慢速循環伏安分析 129
第五章 結論 130
第六章 參考文獻 131

1. Tarascon, J.M. and M. Armand, “Issues and challenges facing rechargeable lithium batteries” Nature., 2001, 414, 359-367.
2. 黃炳照，”鋰離子電池技術”，台灣化學工程學會誌，2011，58卷第5期，1-9.
3. 費定國，”鋰離子電池在電動車市場之展望”，工業材料雜誌，2006，229期，141-146.
4. 楊模華，”鋰電池材料技術發展”，工業材料雜誌，2006，237期，135-144.
5. J. Yamaki, S. Tobishima, K. Hayashi, K. Saito, Y. Nemoto, M. Arakawa, “A consideration of the morphology of electrochemically deposited lithium in an organic electrolyte”, J. Power Sources., 1998, 219, 74.
6. M. Armand, D. W. Murphy, J. Broadhead, B. C. H. Steele, “Materials for Advanced Batteries” Plenum press, New York., 1980, 145, 381.
7. A. K. Padhi, K. S. Nanjundaswamy, and J. B. Goodenough. “Phospho-olivines as Positive-Electrode Materials for Rechargeable Lithium Batteries” J. Electrochem. Soc., 1997, 144, 1188-1194.
8. A. K. Padhi, K. S. Nanjundaswamy, C. Masquelier, S. Okada, J. B. Goodenough, “Effect of Structure on the Fe3+/Fe2+ Redox Couple in Iron Phosphates” J. Electrochem. Soc., 1997, 144, 1609–1613.
9. S. Andersson and J. O. Tomas, “The source of first-cycle capacity loss in LiFePO4”J. Power Sources., 2001, 498, 97-98.
10. A. B. D. Nandiyanto, K. Okuyama, “Progress in developing spray-drying methods for the production of controlled morphology particles: From the nanometer to submicrometer size ranges” Advanced Powder Technology., 2011, 22, 1–19.
11. F. Gao, Z. Tang, J Xue, “Preparation and characterization of nano-particle LiFePO4 and LiFePO4/C by spray-drying and post-annealing method” Electrochimica Acta., 2007, 53, 1939–1944.
12. F. Yu, J. Zhang, Y. Yang, G Song, “Preparation and characterization of mesoporous LiFePO4/C microsphere by spray drying assisted template method” J. Power Sources., 2009, 189, 794-797.
13. Q. B. Liu, S. J. Liao, H. Y. Song, Z. X. Liang, “High-performance LiFePO4/C materials: Effect of carbon source on microstructure and performance” J. Power Sources.,2012, 211,52-58
14 Yamada, S. C. Chung, K. Hinokuma, “Optimized LiFePO4 for Lithium Battery Cathodes” J. Electrochem. Soc., 2001, 148, 224–229.
15. H. C. Kang, D. K. Jun, B. Jin, E. M. Jin, K. H. Park, H. B. Gu, K. W. Kim, “Optimized solid-state synthesis of LiFePO4 cathode materials using ball-milling” J. Power Sources., 2008, 179, 340-346.
16. B. Q. Zhu, X. H. Li, Z. X. Wang, H. J. Guo, Mater. Chem. “Novel synthesis of LiFePO4 by aqueous precipitation and carbothermal reduction“ Mater. Chem. Phys., 2006, 98, 373-376.
17. C. H. Mi, G. S. Cao, X. B. Zhao, “Low-cost, one-step process for synthesis of carbon-coated LiFePO4 cathode” Mater. Lett.,2005, 59, 127–130.
18. L. Wang, G. C. Liang, X. Q. Ou, X. K. Zhi, J. P. Zhang, J. Y. Cui, “Effect of synthesis temperature on the properties of LiFePO4/C composites prepared by carbothermal reduction” J. Power Sources., 2009, 189, 423-428.
19. M. Higuchi, K. Katayama, Y. Azuma, M. Yukawa, M. Suhara, “Synthesis of LiFePO4 cathode material by microwave processing ” J. Power Sources., 2003, 119–121, 258–261.
20. L. Wang, Y. Huang, R. Jiang, D. Jia, “Preparation and characterization of nano-sized LiFePO4 by low heating solid-state coordination method and microwave heating” Electrochim. Acta., 2007, 52, 6778–6783.
21. A. V. Murugan, T. Muraliganth, A. Manthiram, “Rapid microwave - solvothermal synthesis of phosphor-olivine nanorods and their coating with a mixed conducting polymer for lithium ion batteries“ Electrochem. Commun., 2008, 10, 903–906.
22. S. Yang, P. Y. Zavalij, M. S. Whittingham, “Hydrothermal synthesis of lithium iron phosphate cathodes” Electrochem. Commun., 2001, 3, 505-508.
23. J. Chen, M. S. Whittingham, “Hydrothermal synthesis of lithium iron phosphate” Electrochem. Commun., 2006, 8, 855–858.
24. K. Kanamura, S. Koizumi, K. Dokko, “Hydrothermal synthesis of LiFePO4 as a cathode material for lithium batteries” J. Mate. Sci., 2008, 43, 2138-2142.
25. K. Dokko, S. Koizumi, K. Sharaishi, K. Kanamura, “Electrochemical properties of LiFePO4 prepared via hydrothermal route” J. Power Sources., 2007, 165, 656–659.
26. G. Meligrana, C. Gerbaldi, A. Tuel, S. Bodoardo, N. Penazzi, “Hydrothermal synthesis of high surface LiFePO4 powders as cathode for Li-ion cells”J. Power Sources., 2006, 160, 516–522.
27. K. S. Park, J. T. Son, H. T. Chung, S. J. Kim, C. H. Lee, H. G. Kim, “Synthesis of LiFePO4 by co-precipitation and microwave heating” Electrochem. Commun., 2003, 5, 839–842.
28. G. Arnold, J. Garche, R. Hemmer, S. Strobele, C. Vogler, M. W. Mechren, “Fine-particle lithium iron phosphate LiFePO4 synthesized by a new low-cost aqueous precipitation technique“ J. Power Sources., 2003, 119, 247–251.
29. J. C. Zheng, X. H. Li, Z. X Wang, H. J. Guo, S. Y. Zhou,“LiFePO4 with enhanced performance synthesized by a novel synthetic route” J. Power Sources., 2008, 184, 574–577.
30. 費定國、黃楷斌，” 鋰離子電池陰極材料LiFePO4近年研究進展(上)”，工業材料雜誌，2009，274期，163-167.
31. F. Croce, A. D. Epifanio, J. Hassoum, A. Deptula, T. Olczac, B. Scrosatia, “A novel concept for the synthesis of an improved LiFePO4 lithium battery cathode” Electrochem. Solid-State Lett., 2002, 5, A47-A50.
32. D. Choi, P. N. Kumta, ”Surfactant based sol–gel approach to nanostructured LiFePO4 for high rate Li-ion batteries” J. Power Sources., 2007, 63, 1064–1069.
33. 費定國、黃楷斌，” 鋰離子電池陰極材料LiFePO4近年研究進展(中)”，工業材料雜誌，2009，275期，127-136.
34. M.-R. Yang, T.-H. Teng, S.-H. Wu, “LiFePO¬4/carbon cathode materials prepared by ultrasonic spray pyrolysis” J. Power Sources., 2006, 159, 307-311.
35. M. Konarova, I. Taniguchi, “Preparation of LiFePO4/C composite powders by ultrasonic spray pyrolysis followed by heat treatment and their electrochemical properties” Mater. Res. Bull., 2008, 43, 3305-3317.
36. K. Zaghib, P. Charest, A. Guerfi, J. Shim, M. Perrier, K. Striebel, “Safe Li-ion polymer batteries for HEV applications” J. Power Sources., 2004, 134, 124–129.
37. Nonglak Meethong, et al., “Aliovalent Substitutions in Olivine Lithium Iron Phosphate and Impact on Structure and Properties” Adv. Funct. Mater., 2009, 19, 1060-1070.
38. H. Liu, C. Li Q. Cao, Y. P. Wu and R. Holze, “Effects of heteroatoms on doped LiFePO4/C composites” J. Solid State Electrochem., 2008, 12, 1017-1020.
39. S. L. Bewlay, K. Konstantinov, G. X. Wang, S. X. Dou, H. K. Liu, “Conductivity improvements to spray-produced LiFePO4 by addition of a carbon source” Mater. Lett., 2004, 58, 1788-1791.
40. Wei-Jun Zhang, “Structure and performance of LiFePO4 cathode materials: A review” J. Power Sources, 2011, 196, 2962–2970.
41. T. Nakamura , Y. Miwa , M. Tabuchi , Y. Yamada, “Structural and surface modifications of LiFePO4 olivine particles and their electrochemical properties.” J. Electrochem. Soc., 2006, 153, A1108-A1114.
42. S. W. Song , R. P. Reade , R. Kostecki , K. A. Striebel, “Electrochemical studies of the LiFePO4 thin films prepared with pulsed laser deposition.”, J. Electrochem. Soc., 2006, 153, A12.
43. Chung,S.-Y., et al., “Electronically conductive phospho-olivines as lithium storage electrodes” Nat. Mater., 2002, 1, 123-128.
44. H. Liu, G. X. Wang, D. Wexler, J. Z. Wang, H. K. Liu, “Electrochemical performance of LiFePO4 cathode material coated with ZrO2 nanolayer” Electrochem. Commun.,2008, 10, 165–169.
45. H. Liu, C. Li, H. P. Zhang, L. J. Fu, Y. P. Wu, H. Q. Wu, “Kinetic study on LiFePO4/C nanocomposites synthesized by solid state technique” J. Power Sources, 2006, 159, 717.
46. Y. Hu., M. M. Doeff, R. Kostecki, R. Finones, “Electrochemical performance of sol-gel synthesized LiFePO4 in lithium batteries” J. Electrochem. Soc., 2004, 151，A1279-A1285.
47. Kuei-Feng Hsu, Sun-Yuan Tsay, Bing-Joe Hwang, “Physical and electrochemical of properties of LiFePO4/Carbon composite synthesized at various pyrolysis periods” J. Power Sources, 2005, 146, 529-533.
48. K. F. Hsu, S. Y. Tsay, B. J. Hwang, “Synthesis and characterization of nano sized LiFePO4 cathode materials prepared by a citric acid-based sol-gel route” J. Mater. Chem, 2004, 14, 2690-2695.