指導教授 : 王振乾 教授 學生 : 林振崑

Abstract Poly(AN-co-GMA-IDA) has been prepared by copolymerizing acrylonitrile (AN) and 2-methylacrylic acid 3-(bis- carboxymethylamino-2-hydroxy-propyl ester) (GMA-IDA). FT-IR has revealed that the GMA-IDA unit can improve the dissociation of the lithium salt. GMA-IDA can hinder the crystallization of EC, thereby improving the conductivity of the gel polymer electrolytes (GPE). The maximum conductivity measured in this investigation was 9.75×10 −4 Scm −1.

Introduction Gel polymer electrolytes (GPE) have been attractive for the development of plastic Li ion batteries since they combine the advantages of liquid electrolytes (high ionic conductivity) and polymers (free from leaks, good mechanical strength). These systems display high ionic conductivity at room temperature and have sufficient mechanical strength. Found that introducing the monomer (3-(bis-carboxymethylamino- 2-hydroxy-propyl ester)) (GMA-IDA) into a polyacrylonitrile (PAN) matrix by copolymerization not only increased the mechanical properties, but also enhanced the miscibility of the polymer and liquid electrolyte.

In this study, ethylene carbonate (EC) has been used as a liquid electrolyte with a view to more effectively exploiting the advantage of –COO - Li + in increasing the conductivity of a GPE. Moreover, the polar groups of GMA-IDA can prevent the crystallization of EC, thereby expanding the range of temperatures at which it can be applied. Introduction

Materials Glycidyl methacrylate (GMA) Iminodiacetic acid (IDA) lithium hydroxide (LiOH) Acrylonitrile (AN) Ammonium peroxodisulfate (APS) Ethylene carbonate (EC) Lithium perchlorate (LiClO 4 )

Experimental 將 GMA-IDA 和 AN 加入反應器中 通氮氣 攪拌, 溫度達到 60°C, 加入過硫酸胺 (APS), 開始聚合 24H 反應結束後, 將產物倒入乙 醇中沉澱, 然後過濾, 烘乾. AN:GNA-IDA mole 比 1:0.02 AG1 1:0.06 AG2 1:0.10 AG3

Experimental Ethylene carbonate (EC) P(AN-co-GMA-IDA) 混合 塑化聚合物電解質 polymer/plasticizer 成分比 50:50 and 40:60 wt%

Results and discussion Characterization of the copolymers

Results and discussion Characterization of the plasticized polymer (FT-IR)

Results and discussion Characterization of the plasticized polymer (FT-IR)

Results and discussion Characterization of the plasticized polymer ( 7 Li MAS NMR) GMA-IDA 的 -COO - Li + 的鋰離子 GMA-IDA 上螯合基的鋰離子 與 EC 作用的鋰離子 判斷 GMA-IDA 在塑化 聚合物, EC 與 -COO - Li + 的鋰離子在不同環境 的交互作用 這結果證實上面敘述 FT-IR 的分析結果

Results and discussion Characterization of the plasticized polymer (DSC&XRD)

Results and discussion Lithium ions in the plasticized polymers 看到, GMA-IDA 含量增加, 可以提高鋰鹽的解離, 所以 GMA-IDA 加入對鋰鹽解離是 有幫助的。 ClO 4 - 吸收峰 LiClO 4 離子對 吸收峰

Results and discussion Ionic conductivity 溶於不同離鹽濃度, 導電度隨 GMA- IDA 增加而增加. GMA-IDA 在 P(AN-co-GMA-IDA)/EC 的 系統影響還包括 : (1)GMA-IDA 會阻礙 EC 結晶 (2)EC 對 -COO - Li + 的鋰離子運動性有很大 的幫助 (3)GMA-IDA 有助於鋰鹽的解離 AG3/EC 40:60 wt.% with LiClO 4 at 3mmolg −1 polymer displayed the highest conductivity of 9.75×10 −4 Scm −1

Results and discussion Mechanical strength AG3/EC 40:60 wt.% system (Young’s modulus= 0.76MPa, toughness = MPa) PAN/PC 20:80 wt.% system (Young’s modulus=0.18MPa,toughness = 4.30MPa) 機械強度比典型的 PAN 系統好

Conclusions Analytical results have revealed a significant interaction between the GMA-IDA and EC. AG3/EC 40:60 wt.% systemhas been shown to provide a polymer electrolyte that displays good conductivity(9.75×10−4 Scm−1) and good mechanical strength. This interaction gives rise to three effects: (1) The GMA-IDA unit hinders the crystallization of EC in the GPEs. (2) The mobility of Li + in the –COO−Li + units increases with the amount of EC added, and hence the number of charge carriers in the GPE increases, improving the ionic conductivity. (3) The GMA-IDA unit increases the dissociation of the lithium salt and reduces the ion aggregation in the GPEs.