表面改性纳米SiO_2复合聚合物电解质的制备及性能

Preparation and Characterization of Composite Polymer Electrolytes Containing Surface-modified Nano Silica

通过化学方法将具有增塑效果的环状碳酸酯基团引入纳米SiO2表面,并用FTIR与TGA对改性纳米SiO2进行了表征.将改性纳米SiO2添加到以聚氧化乙烯(PEO)为基体的聚合物电解质中,制备了复合聚合物电解质.通过DSC和交流阻抗等方法对该聚合物电解质膜的热力学和电化学性能进行了研究.结果表明,掺杂改性纳米SiO2的聚合物电解质具有更高的离子电导率,室温最高离子电导率可达到1.84×10-5 S/cm;具有较高的锂离子迁移数,最高可达到0.49,且具有更好的界面稳定性.

Nano silica with carbonate groups were synthesized by the esterification reaction and the structure of the modified nano silica were characterized by FTIR and TGA methods. The composite polymer electrolytes （CPEs） were prepared by introducing the modified nano silica. The thermal and electrochemical performances of the CPEs were studied by DSC and AC impedance. The results show that the addition of modified nano silica enhance the thermal properties and ionic conductivities of CPEs, and meanwhile the lithium ion transference number of CPEs increase up to 0. 49. AC impedance results reveal that modified nano silica can also improve the interfacial stability between CPEs and lithium metal electrode.