由於各種可攜帶式電器的發展，使得提供電源的元件越顯重要。鋰電池由1980年代被發明以來，由於其高能量密度而受到重視，對於鋰/鋰離子電池的研究發展逐漸完善。但因應電子元件在尺度上追求輕薄短小的趨勢。電源供應元件，如鋰離子電池，之微型化薄膜化將具有極大優勢。但其技術瓶頸則在於固態電解質之穩定性及導電性。若能有效將固態無機電解質導電性及穩定性提升，將有助於薄膜化鋰離子電池之拓展與應用。
本研究以具有NASICON結構之LiTi2(PO4)3 (簡稱LTP)固態電解質為主題，以固相反應法摻雜異價陽離子Al3+及Li+，以取代的方式改變結構中帶電粒子(鋰離子)及空缺的濃度，並探討其燒結後之顯微結構、相穩定性、導電性質及全固態電池開路電壓之影響。
當Al及Li的添加量由0增加至40%，換言之Li1+xAlxTi2-x(PO4)3 x=0~0.4時，燒結後由XRD分析，可推論Al3+離子可取代Ti4+的位置，但仍維持LTP的菱方相結構。並因為離子半徑大小的差異，晶格由a=8.5101Å，c=20.8445Å縮小為a=8.495Å，c=20.7785Å。
而化學組成Li1+xAlxTi2-x(PO4)3在x=0.5至1.0，則出現一斜方相LATP之第二相，並隨著鋁成分增加而所佔體積分率隨著增加。根據CaRIne軟體模擬結果，此相是由於八面體中心原子的價數改變，使得氧原子和中心原子鍵結角度、長度之改變而形成。
而由顯微結構之觀察、燒結性質之測試可知鋁的取代對於Li1+xAlxTi2-x(PO4)3整體系統之燒結性質會有正面的影響。由於隨著鋰、鋁添加量的增加，孔隙率逐漸的下降，緻密度提升，主要的原因是燒結速率的控制因子在於以陽離子的擴散為其主導，和橄欖石結構相同。因此當鋰添加後，會產生陽離子之空缺，增進陽離子的擴散，使試片緻密性質上升。
至於鋰、鋁添加量對導電性質之影響，以理論公式計算，離子導電率受載子及空缺影響重大。未添加的LTP其導電性質為10-6S/cm，經由鋁取代後，最高導電率之組成為Li1.3Al0.3Ti1.7(PO4)3，可達8.16x10-4S/cm，接近高分子電解質的導電區間；由導電率曲線變化圖可知斜方相的產生並不利於鋰離子之傳導，若要使用Li1+xAlxTi2-x(PO4)3材料系統作為電解質使用，應當避免斜方相產生之區間。
最後，以鋰金屬做為陽極，空氣作為陰極反應物及Li1+xAlxTi2-x(PO4)3材料系統作為電解質使用，發現Li1+xAlxTi2-x(PO4)3材料系統作為電解質可維持開路電壓在2.0volt以上。隨時間變化，並未觀察到明顯的電壓值的下降。顯示Li1+xAlxTi2-x(PO4)3材料系統作為電解質使用也具有適當的穩定性。

Since the portable electronic device has becoming more and more popular, lithium-ion batteries which are the main power sources have shown rapid growth in the past years. To further reduce the volume of power source, the development of solid state lithium-ion batteries using inorganic electrolyte is desired. The main advantage of using inorganic electrolyte is the feasibility of using thin film process.
In this study, the NASICON-type LiTi2(PO4)3-based compound was studied. Extensive investigations have been focused on the introduction of aliovalent ions, Al+3, in LiTi2(PO4)3 to improve its conductivity. The objective of this work is to study the effect of Al2O3 addition on the phase change, conductivity and sintering properties of Li1+xAlxTi2-x(PO4)3 system.
For the samples with the composition corresponding to Li1+xAlxTi2-x(PO4)3, x=0~0.4, based on XRD analysis, all diffraction lines were indexed based on a rhombohedral structure (space group ). Very small amount of TiP2O7 was found in undoped LiTi2(PO4)3 as a result of lithium loss during calcining and sintering process. Since no additional peaks appeared as Al3+ ion replaced Ti4+ ion, it inferred that added Al3+ ions tend to replace Ti4+ ions completely. As a result, the lattice parameter in Li1+xAlxTi2-x(PO4)3 systems decreased from a=8.5101Å, c=20.8445Å to a=8.495Å, c=20.7785Å when 40% of Ti4+ sites were substituted by Al3+ ions.
As the substitution level went over 50%, a second phase with orthorhombic lattice appeared. The fraction of the orthorhombic phase increased as the aluminum addition increased. The presence of orthorhombic phase was resulted from the difference in the ion size and valence after substitution. The substitution changes the bonding length and bonding angle between the central cations and oxygen ions in the (Ti,Al)O6 octahedra.
The microstructures of sintered LATP were observed by SEM. The densification of LATP pellets was improved by the addition of aluminum ions. It is believed that the cation diffusion is the rate-limiting step in the sintering of Li1+xAlxTi2-x(PO4)3.
The ionic conductivity of Li1+xAlxTi2-x(PO4)3 was strongly influenced by the charge carrier concentration and vacancy concentration available in the lattice. When x=0.3, the maximum conductivity of 8.16x10-4S/cm was obtained. When x>0.4, the conductivity drops drastically due to the presence of the low-conductivity orthorhombic phase.
Finally, a Li-battery using Li1+xAlxTi2-x(PO4)3 system as the electrolyte was assembled and tested. The cell testing showed very stable open circuit voltage ~2.5 V without noticeable degradation. This result indicates that Li1+xAlxTi2-x(PO4)3 system with adequate stability and conductivity may be a good candidate for all solid state lithium ion battery applications.

1. H.V. Venkatasetty, Lithium Battery Technology, (1984)chap.1.

2. J.B. Bates, N.J. Dudney, B. Neudecker, A. Ueda, C.D. Evans, Solid State Ionics 135 (2000) p.33-45

3. 林振華、林振富,充電式鋰離子電池-材料與應用,全華科技圖書股份有限公司,民國90年12月出版

4. J.Hajek, French Patent 8 (1949) p.10

5. D. Fouchard and J. B. Taylor, Journal of Power Sources, 21, 3-4 (1987) p.195

6. J. P. Gabano, Lithium Batteries, Academic Press, London, (1983)

7. 李敏昌, 工業材料, 110 期85 年2 月 p.74-82

8. S. Subbarao, The Electrochemical Society, (1990)

9. 費定國、高東漢, 化學, 47, 1(1989) p.47-56

10. 楊家諭, 工業材料, 144 期87 年12 月, p.66

11. 楊家諭、鄭賢豪, 工業材料, 117 期85 年9 月p.71-78

12. M. B. Armand and J. M. Chabagno, Fast Ion Transport in Solid, (1979)

13. 楊家諭, 工業材料, 122 期86 年2 月 p. 126-133

14. M. Gauthier, A. Belanger, P. Bouchard, Journal of Power Sources,54(1995) p.163-169

15. M. Gauthier, M. Armand, L. Krause, Seventh International Meeting on Lithium Batteries, Boston, May15-20(1994)

16. F. Boudin, X. Andrieu and C. Jehoulet, Journal of Power Sources, 82(1999), p.804-807.

17. T. Lehtinen, G. Sundholm and F. Sundholm, Journal of Applied Electrochemistry, 29, 6(1999), p.677-683.

18. D. Ostrovskii, A. Brodin, LM. Torell, GB. Appetecchi and B. Scrosati, Journal of Chemical Physics, 109, 17(1998), p.7618-7624

19. B. K. Choi, K. H. Shin and Y. W. Kim, Solid State Ionics, 11, NSI5(1998) p.123-127.

20. G. Pistoia, Lithium Batteries, (1994) p.109.

21. J. B. Bates, N. J. Dudney, B. Neudecker, A. Ueda and C. D. Evans, Solid State Ionics 135 (2000) p.33–45

22. P. Birke, W. F. Chu and W. Weppner, Solid State Ionics, 93 (1997) p.1-15.

23. 林素琴, 工研院電子報 第9810期

24.David Linden, Thomas B.reddy著, 汪繼強 譯, 電池手冊, 化學工業出版社

25. Lin Shi-Chun and Lin Zu-Xiang, Solid State Ionic 9&10 (1983) p.835-838

26. H. Y-P. Hong, Mat.Res,Bull,11(1976) p.173-182

27. B. E. Taylor, A.D. English and T. Berzins, Mat.Res,Bull,12, (1977) p.171-181

28. H. Aono , E. Sugimoto , Y. Sadaoka, N. Imanaka and Gin-ya Adachi, J. Electrochem. Soc.137, (1990) p.1023-1027

29. H. Aono , E. Sugimoto , Y. Sadaoka, J. Electrochem. Soc.136 (1989) p.590-591

30. W. H. Flygare and R. A. Huggins, Journal of Physics Chemistry, Solids, 34 (1973) p.1199-1204.

31. F. C. Walsh , Trans. Inst. Metal Finish, 70, 1(1992) p.45-49.

32. K.Takada et al. Solid State Ionic 139, (2001) p.241-247

33. Joykumar S. Thockchom and Binod Kumar, Journal of the American Ceramic Society, 90 (2007) p.462-466

34. E. Kazakevicius,T.Salkus, A. Dindune, Z. Kanepe, J. Ronis, A. Kezionis, V. Kazlauskiene, J. Miskinis, A. Selskiene, A. Selskis, Solid State Ionic 179 (2008) p.51-56

35. Y. kobayashi, T. Takeuchi, M. Tabuchi, Kazuaki Ado, H. Kageyama, Journal of Power Source 81-82, (1999) p.853-858

36. Chae-Myung Chang, Young Il Lee, Seong-Hyeon Hong, J. Am. Ceram. Soc., 88 (2005) p.1803-1807

37. J. Wolfenstine, D. Foster, J. Read, J.L. Allen, Journal of Power Sources 182 (2008) p.626-629

38. A. Aatiq, M. Menetrier, L. Croguennec, E. Suard, C. Dlemas, Journal of Materials Chemistry, 12 (2002) p.2971-2978

39. C. Delmas, A. Nadiri, Solid State Ionic 28-30 (1988) p.419-423

40. A. D. Robertson et al., Solid State Ionic 104 (1997) p.1-11

41. 張嘉峰,薄膜鋰離子電池固態電解質的製程研究 國立清華大學材料所碩士論文,(2005)

42. Sébastien Patoux, Gwenaëlle Rousse, Jean-Bernard Leriche, Christian Masquelier, Solid State Sciences 6 (2004) p.1113–1120

43. I. A. Stenina, Yu. A. Velikodnyi, V. A. Ketsko and A. B. Yaroslavtsev, Inorganic Materials, Vol. 40, No. 9, (2004) p.967–970

44. A. Ignaszak, P. Pasierb, R. Gajerski, S. Komornicki, Thermochimica Acta 426 (2005) p.7–14

45. Enrique R. Losilla, Sebastia´n Bruque, Miguel A.G. Aranda, Laureano Moreno-Real, E. Morin , M. Quarton, Solid State Ionics 112 (1998) p.53–62

46. I.A. Stenina, M.N. Kislitsyn, N.A. Ghuravlev, A.B. Yaroslavtsev, Materials Research Bulletin 43 (2008) p.377–383

47. Takahito Suzuki, Kenji Yoshida, Kazuyoshi Uematsu, Tatsuya Kodama, Kenji Toda, Zuo-Guang Ye and Mineo Sato, Solid State Ionics 104 (1997) p.27-33

48. Enrique R. Losilla, Miguel A. G. Aranda, Marı´a Martı´nez-Lara, and Sebastia´n Bruque, Chem. Mater. 9 (1997) p.1678-1685

49. Michele Catti, Angiolina Comotti, Silvia Di Blas and Richard M. Ibberson, Journal of Materials Chemistry 14 (2004) p.835–839

50. A. B. Yaroslavtsev and I. A. Stenina, Russian Journal of Inorganic Chemistry 51 (2006) p.S97-S116

51. S. Hamdoune, D. Tran Qui, Solid State Ionics 18&19 (1986) p.587-591

52. S. Hamdoune, M. Gondrand, D. Tran Qui, Materials Research Bulletin. 21 (1986) p.237-242

53. D. Tran Qui, S. Hamdoune, Acta crystallographica. C44, (1988) p.1360-1362

54. Michele Catti, Journal of Solid State Chemistry 156, (2001) p.305-312

55. Michele Catti, Angiolina Comotti, Silvia Di Blas and Richard M. Ibberson, Journal of Materials Chemistry, 14 (2004) p.835-839

56. 卓駿堯, La1-xSrxVO3系陽極材料經體結構導電性質及製程方法之研究, 國立成功大學材料科學及工程學系碩士論文, (2010)

57. 張智豪, 陽離子之置換對xLnAlO3-(1-x)CaTiO3系與Zn(Ta，Nb)2O6系高頻介電陶瓷之晶體結構與電性之影響, 國立成功大學材料科學及工程學系碩士論文, (2004)

58. H. Kohler, H. Schulz, Materials Research Bulletin. 20 (1985) p.1461-1471

59. A.B. Yaroslavtsev, I.A. Stenina, Russian Journal of Inorganic Chemistry.51 (2006) p.97-115

60. J. Wolfenstine , J.L. Allen , J. Sumner, J. Sakamoto, Solid State Ionics 180 (2009) p.961–967

61. J.L. Narváez-Semanate, A.C.M. Rodrigues, Solid State Ionics 181 (2010) p.1197–1204

62. Oliver Jaoul, Bernard Houlier. Journal of Geophysical Research, 88, (1983) p.613-624

63. Amy J.G. Jurewicz, E. Bruce Watson. Contributions to Mineralogy and Petrology, 99, (1988) p.186-201

64. Frederic Bejina, Olivier Jaoul. Earth and Planetary Science Letters, 153 (1997) p.229-238

65. C. J. Leo, B. V. R. Chowdari, G. V. Subba Rao, J. L. Souquet, Materials Research Bulletin 37 (2002) p.1419-1430

66. J. Fu, Solid State Ionics 104 (1997) p. 191

67. H. Aono, E. Sugimoto, Y. Sadaoka, N. Imanaka, G. Adachi, Solid State Ionics 47 (1998) p.257.

68. 曾怡仁，BaZrO3添加對La0.57Li0.3TiO3晶體結構與導電性質的影響,國立成功大學材料科學及工程學系碩士論文, (2003)