Polymeric Electrolytes for Solid‐state Lithium Ion Batteries: Structure Design, Electrochemical Properties and Cell Performances

Abstract Solid‐state electrolytes are key to achieving high energy density, safety, and stability for lithium‐ion batteries. In this Review, core indicators of solid polymer electrolytes are discussed in detail including ionic conductivity, interface compatibility, mechanical integrity, and cycling stability. Besides, we also summarize how above properties can be improved by design strategies of functional monomers, groups, and assembly of batteries. Structures and properties of polymers are investigated here to provide a basis for all‐solid‐state electrolyte design strategies of multi‐component polymers. In addition, adjustment strategies of quasi‐solid‐state polymer electrolytes such as adding functional additives and carrying out structural design are also investigated, aiming at solving problems caused by simply adding liquids or small molecular plasticizer. We hope that fresh and established researchers can achieve a general perspective of solid polymer electrolytes via this Review and spur more extensive interests for exploration of high‐performance lithium‐ion batteries.