Breaking the Trade‐Off between Ionic Conductivity and Mechanical Strength in Solid Polymer Electrolytes for High‐Performance Solid Lithium Batteries

Abstract Solid polymer electrolytes (SPEs) are among the most promising candidates for solid‐state batteries due to their easy processibility, interface compatibility, and cost efficiency. However, the trade‐off between the ionic conductivity and mechanical strength of SPEs, which has persisted for decades, hinders their application in solid‐state lithium (Li) metal batteries. In this study, the aim is to break this trade‐off by utilizing poly(p‐phenylene benzobisoxazole) (PBO) nanofibers as a mechanically strong backbone and polyethylene oxide (PEO) as an ionically conductive network. The PBO/PEO composite electrolyte reduces the crystallinity of PEO while increasing the mechanical strength (74.4 MPa, ≈14…

• NN
  National Natural Science Foundation of China

  Awards: 22379108, 52202279
• NK
  National Key Research and Development Program of China

  Award: 2021YFF0500600