PEO-PAN-PEO三明治结构新型固态聚合物电解质的研究

A novel all-solid-state polymer electrolyte based on PEO-PAN-PEO sandwich structure

摘要:

为了解决聚丙烯腈（PAN）聚合物电解质膜刚性强、界面接触状况差的问题，将聚氧化乙烯 (PEO)电解质膜贴合在PAN电解质膜的两侧，形成三明治结构PEO-PAN-PEO新型聚合物电解质复合膜. 在高温下PEO层具有的柔性大幅度增加了电极与电解质的接触面积，降低了界面阻抗，成功充当了全固态锂电池的电解质膜. 以金属锂为负极、LiFePO4为正极所组装的全固态锂电池在60oC下工况良好，初始放电比容量是153mAh/g，40周容量保持率为87%.

Abstract:

In order to address the interfacial issues associated with the rigidness of polyacrylonitrile (PAN) polymer electrolyte, polyethylene oxide (PEO) polymer electrolyte layers are firstly proposed to paste on the both sides of PAN membrane, resulting in the formation of a sandwiched PEO-PAN-PEO polymer electrolyte. Under the high temperature, the flexible PEO offers the enlarged contact area between the electrolyte and the electrode with the reduced internal resistance. It indicates that the novel sandwich polymer electrolyte is one of the ideal candidates for all-solid lithium battery. The cell consisting of metallic Li anode and LiFePO4 cathode demonstrates the initial discharge capacity of 153 mAh/g and the capacity retention rate of 87% at 40th cycle under the operation temperature of 60℃.