利用具環氧官能基高分子交聯合成之有機無機雙核狀固(膠)態高分子電解質結構鑑定與動力學研究

Synthesis, Structure Characterization and Dynamic Properties of an Organic-Inorganic Hybrid Polymer Electrolyte Based on Polyether Epoxy.

趙虹宇(Hung-Yu Chao)

指導教授 ： 高憲明

國立中央大學/理學院/化學系/碩士(2012年)

摘要

本論文分為兩大部分，第一部分是利用三聚氯氰作為結構核心，以三嵌段共聚高分子 ED2003 作為連接，並以含環氧官能基之高分子 PEGDGE 使之交聯，之後接上矽氧烷 GLYMO，並摻雜不同鋰鹽 (LiClO4) 濃度，合成出一新型雙核狀結構的有機無機固態高分子電解質。接著針對鋰鹽濃度對於高分子電解質的性質影響及鋰離子與高分子鏈段的作用情形作探討：利用熱重分析儀 (TGA) 觀察其熱穩定性；以微差掃描卡計 (DSC) 與 X 光繞射儀 (XRD) 研究高分子鏈段結晶情形；以傅立葉紅外線吸收光譜儀 (FTIR) 對其結構作鑑定並分析鋰鹽解離程度；以交流阻抗分析儀 (AC Impedance) 測量離子導電度、電化學穩定性及鋰離子遷移係數；以掃描式電子顯微鏡 (SEM) 分析其表面形態；以固態核磁共振光譜儀 (SSNMR) 之 13C CP MAS 實驗進行結構鑑定，並利用許多 NMR 技術如 1H-13C 2D WISE、7Li NMR 譜寬量測及鋰離子擴散常數量測等方法了解鋰離子與高分子鏈段運動性之間的動力學分析研究。藉由分析結果發現其導電度隨分子鏈段運動性增加而上升，於室溫下最佳導電度可達到 9.5 × 10-5 S cm-1。
　　第二部分則是將第一部分所合成之固態高分子電解質添加 PVDF-HFP 以增加其機械強度，並吸附含有不同鋰鹽之有機液態電解液，製備成膠態高分子電解質，期望能夠提升離子導電度並應用於鋰電池當中。接著針對其電解液吸附情形作澎潤比測試；以交流阻抗分析儀 (AC Impedance) 測量離子導電度與電化學穩定性，得知此膠態高分子電解質於室溫下最佳導電度可達到 6.9 × 10-5 S cm-1，且可承受到約 4.5 V 之氧化分解電壓；最後進一步組裝成硬幣型 2032 電池，對其電池充放電性能作探討。

關鍵字

固態高分子電解質 ； 鋰離子電池 ； 離子導電度 ； 膠態高分子電解質

並列摘要

A new hyperbranched organic-inorganic hybrid electrolyte based on the use of 2, 4, 6-trichloro-1, 3, 5-triazine (cyanuric chloride, CC) as the coupling core to couple with oligo (oxyalkylene)-amines and poly (ethylene glycol) diglycidyl ether (PEGDGE), followed by condensation with 3-glycidyloxypropyl-trimethoxysilan (GLYMO) then complexed with LiClO4 has been prepared and characterized.
　　The structure and performance of the polymer electrolytes for lithium ion batteries use, including thermal stability, ionic conductivity, salt dissolvability, surface morphology, electrochemical stability, were studied by thermogravi-metric analyzer (TGA), AC impedance, Fourior transform infaraed spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron spectroscopy (SEM), 13C cross-polarization magic-angle spinning (CPMAS). The Vogel-Tamman-Fulcher (VTF)-like conductivity behavior is observed in the present solid polymer electrolyte (SPE) with a maximum ionic conductivity is 9.5 × 10-5 S cm-1 at 30 ?C. Multinuclear NMR techniques are used to provide a microscopic view for the specific interaction between the polymer chains and Li+ cations and their dynamic behaviors. The results of 2D 1H-13C wide-line separation (WISE) and 7Li static line NMR width measurements reveal that the mobility of the 7Li cations are strongly related to a dynamic environment created by the polymer chains motion in the amorphous phase. The combined results of conductivity and 7Li pulse-gradient spin-echo (PGSE) NMR self-diffusion coefficient measurements reveal that the ionic conductivity enhancement at low salt concentrations is mainly caused by the high mobility of the lithium cations.
　　Then the swelling ratio and the ionic conductivity of the electrolyte membranes are measured with different liquid electrolyte solutions, the gel polymer electrolytes (GPEs) represents the highest ionic conductivity as 6.9 × 10-3 S cm-1 at 30 ?C and with sufficient electrochemical stability up to 4.5 V. Hence, it can be concluded that this new hybrid polymer system is suitable for use as a GPE in rechargeable lithium batteries.

並列關鍵字

Lithium ion battery ； Solid polymer electrolyte (SPE) ； Gel polymer electrolyte(GPE) ； Ionic conductivity

參考文獻

(75) 高憲明 NMR化工技術, 固態核磁共振技術於材料化學之應用與研究, 166.

(5) Peled, E. J. Electrochem. Soc. 1979, 126, 2047.

(8) Xu, K. Chem. Rev. 2004, 104, 4303.

(9) Matsui, T.; Takeyama, K. Electrochim. Acta 1995, 40, 2165.

(10) Osaka, T.; Homma, T.; Momma, T.; Yarimizu, H. J. Electroanal. Chem. 1997, 421, 153.