凝胶型聚合物电解质中离子的溶剂化与缔合的研究

AN INVESTIGATION OF ION SOLVATION AND ION ASSOCIATION IN A GEL TYPE SOLID POLYMER ELECTROLYIT

考察了聚（三乙二醇甲基丙烯酸二酯）－ＬｉＣｌＯ＿４－溶剂三组分凝胶固体电解质中离子溶剂化和缔合现象，发现电解质中自由离子摩尔百分数随ＬｉＣｌＯ＿４盐浓度的提高而线性下降，离子对摩尔百分数先增加后减小，而三离子摩尔百分数则随盐浓度增加而线性增加。在盐浓度为０．５ｍｏｌ／Ｌ～１．５ｍｏｌ／Ｌ时，聚合物电解质的离子电导主要由三离子所贡献。但各离子摩尔百分数随温度变化的情况因溶剂不同而不同。以四乙二醇为增塑剂时，自由离子和离子对百分数随温度升高而增大，而三离子百分数则随温度升高而降低；以ＰＥＧ４００为增塑剂时，各离子百分数随温度变化的趋势不十分明显，只是在高温（７０～８５℃）时才明显一些。本文还讨论了自由离子和三离子体对电导的贡献。

Ion solvation and ion association in″Polytriethylene glycol dimethacrylate-LiClO4-solvent″gel type solid electrolyte were investigated.It was found that free ion mole percentage in the electrolyte decrases lineally with increasing LiClO4 concentration. Ion pair mole percentage increases firstly with increasing LiClO4 concentration and then fails down. But triple ion mole percentage increases lineally when the LiClO4 concentration increases. And, in the LiClO4 concentration range (0. 5 mol/L～1. 5 mol/L), the ion conductance of the polymer electrolyte is mainly contributed by triple ions.The temperature dependence is very interesting. In the case of tetraethylene glycol as solvent , the free ion and ion pair percentage increase as the temperature is raised. But, in the contrast,the triple ion concentration decreases when temperature is raised from room temperatarue to 85 ℃. It seems that the increase of concentration of free ions and ion pairs results from redissociation of triple ions in high temperature.