固态纳米复合聚合物电解质的离子导电性能研究

Study on the Ionic Conduction of Solid Nanocomposite Polymer Electrolytes

以PEO为基质,复配少量纳米无机填料及低分子乙氧化物,制备出了新型的固态纳米复合聚合物电解质膜,利用交流阻抗法测试了聚合物电解质的离子电导率,对离子导电性能进行了研究。采用CPE元件的模拟电路具有很好的适用性。结果表明当低分子乙氧化物的加入量超过80%时电解质膜的电导率大幅提高,并且PEGDME优于PEG300。电导率在LiPF6加量在O∶Li为8∶1时达到最大,随着LiClO4加量的增加持续增加,随无机盐加量增加电解质膜的成膜性能变差。用多微孔高比表面的纳米SiO2粒子复合有利于改善聚合物的电导率。聚合物电解质离子电导率对温度的依赖关系符合Arrhenius方程。

A novel solid nanocomposite polymer electrolyte based on PEO was prepared, and its ionic conduction properties were studied. An equivalent circuit for SS/SPE/SS was designed, which exhibited good accuracy of the measured AC impedance data. The ionic conductivity of SPE increases abruptly when the content of PEG300 and PEGDME exceed 80%. The effect of the content of inorganic salts (LiPF_6, LiClO_4) was different. A maximum was reached of O∶Li=8∶1 for LiPF_6, but the more the LiClO_4, the bigger the conductivity. The porous nano-SiO_2 with higher surface area was more efficient in enhancing the conductivity. The temperature dependence of ionic conductivity was in accord with Arrhenius equation.