Design Strategies for Polymer Electrolytes with Ether and Carbonate Groups for Solid-State Lithium Metal Batteries

The solid-state lithium metal batteries (SSLMBs) are considered to be promising next-generation batteries because of their high energy density and safety levels. The practical application of the SSLMBs is influenced by the solid polymer electrolytes (SPEs), which are a critical component of the SSLMBs; hence, the structural design of SPEs has always been extensively studied. Herein, the characteristics of polyether with ether groups and polycarbonate with carbonate groups as well as their development will be systematically discussed with respect to the functional groups; additionally, the synergistic effect of two functional groups in a copolymer and promising research directions to design SPEs exhibiting comprehensive performances are investigated. Subsequently, as the key factors affecting the development of SSLMBs with SPEs, the progress of lithium salts and achievements in interfacial modification will be discussed. Finally, the current condition of SSLMBs will be revealed. In addition, future perspectives will be provided to guide the future designs of polymer electrolytes for high-performance SSLMBs.