有机物辅助的硫化物电解质基固态电池

Advance in organics enhanced sulfide-based solid-state batteries

固态电池利用固态电解质替换电解液,为电池的发展提供了高能量密度和高安全性的保障,其中硫化物固态电解质因其高离子电导率等优势受到了广泛关注。然而使用硫化物固态电解质还会面临电极/电解质接触较差、与电极发生界面副反应、空气稳定性差的问题,往往需要与一些有机物配合以改善电池性能,例如有机溶剂、有机电解液或聚合物。本文综述了不同种类有机物对硫化物固态电解质的辅助作用,首先回顾了基于硫化物固态电解质的准固态电池发展现状,分别从正极、电解质、负极及相互界面处添加电解液或溶液的角度,阐述了液体添加对准固态电池产生的界面浸润、构筑保护层等增益作用;其次介绍了聚合物/硫化物复合固态电解质的湿法和干法制备,对比了极性和非极性聚合物黏结剂在制备工艺上的差异,着重分析了有机组分的添加对复合电解质离子电导率等性能的影响;阐述了通过溶液法对复合正极内部界面的改善方法,并补充介绍了薄片状(Sheet-type)电极的制备工艺与发展前景;最后总结了目前有机组分在与硫化物固态电解质配合时面临的难点,展望了未来研究工作的发展方向,为组装高性能硫化物基固态电池提供思路。

Using solid-state electrolytes(SSEs)to replace liquid electrolytes(LEs)can guarantee a high energy density and safety for developing solid-state batteries.Sulfide-based SSEs have received much attention because of their significant advantages,like high ionic conductivity.However,they face several challenges:poor electrode/electrolyte contact,interface side reaction with an electrode,and poor air stability.As a common solution,it frequently requires collaboration with some organics,such as organic solvents or polymers,to improve battery performance.This paper reviews the synergistic effects of different organics on sulfide-based SSEs.First,the development status of quasi solid-state batteries(QSSBs)based on sulfide-based SSEs is reviewed.From the perspective of adding LEs or solution at the cathode,electrolyte,anode,and mutual interfaces,the enhancement of adding organics to QSSBs,such as interface infiltration and constructing a protective layer,are described.Second,the wet-and dry-preparation of polymer/sulfide composite SSEs are introduced.The differences in the preparation processes between polar and non-polar polymer binders are compared,and the influence of organics on the ionic conductivity of composite electrolytes is emphatically analyzed.The process of improving the internal interface of the composite cathode using the solution method is described.Moreover,the preparation technology and the development prospect of the sheet-type electrode are introduced.Finally,the difficulties faced using organics in cooperating with sulfide-based SSEs are summarized.Future research work's development directions are proposed,providing ideas for assembling high-performance sulfide-based solid-state batteries.