Polymer Electrode Materials for Lithium-Ion Batteries

Polymer electrode materials (PEMs) have become a hot research topic for lithium-ion batteries (LIBs) owing to their high energy density, tunable structure, and flexibility. They are regarded as a category of promising alternatives to conventional inorganic materials because of their abundant and green resources. Currently, conducting polymers, carbonyl polymers, radical polymers, sulfide polymers, and imine polymers as five kinds of PEMs are studied extensively. This review introduces the latest research progress of PEMs for LIBs from the perspectives of molecular structure, redox mechanism, and electrochemical performance. The synthesis mechanisms and methods are outlined to guide the future design of PEMs. However, the practical application of PEMs is limited by their insufficient conductivity, structural instability, and high solubility. Aiming at these obstacles, reasonable optimization strategies are discussed, including the modification of molecular structure, the control of micromorphology, and the composite of carbon materials. Finally, the development trends and prospects of PEMs are put forward.