Review on Poly(ethylene oxide)-Based Solid Electrolytes: Key Issues, Potential Solutions, and Outlook
Jian-Cang Wang, Weijian Zhou, Nan Zhang, Peng‐Fei Wang, Ting‐Feng Yi
Abstract
Solid polymer electrolytes (SPEs), in comparison to other types of solid electrolytes (SEs), exhibit superior interfacial contact with electrode materials, and their higher flexibility shines in the field of flexible batteries. Among them, poly(ethylene oxide) (PEO) as the earliest proposed and most extensively studied SPE, stands out in terms of mechanical performance and electrochemical stability. However, when PEO is practically applied in all-solid-state lithium-ion batteries (ASSLIBs), its low ionic conductivity, narrow electrochemical window, and poor inhibition of lithium dendrites severely limit its actual application. This review starts from the structure and properties of PEO, analyzes in detail the existing problems of PEO and the mechanisms behind these issues, systematically summarizes the optimization strategies for PEO, and finally prospects the development of PEO-based ASSLIBs.