Toward High Performance Thiophene‐Containing Conjugated Microporous Polymer Anodes for Lithium‐Ion Batteries through Structure Design

Poly(thiophene) as a kind of n‐doped conjugated polymer with reversible redox behavior can be employed as anode material for lithium‐ion batteries (LIBs). However, the low redox activity and poor rate performance for the poly(thiophene)‐based anodes limit its further development. Herein, a structure‐design strategy is reported for thiophene‐containing conjugated microporous polymers (CMPs) with extraordinary electrochemical performance as anode materials in LIBs. The comparative study on the electrochemical performance of the structure‐designed thiophene‐containing CMPs reveals that high redox‐active thiophene content, highly crosslinked porous structure, and improved surface area play significant roles for enhancing electrochemical performances of the resulting CMPs. The all‐thiophene‐based polymer of poly(3,3′‐bithiophene) with crosslinked structure and a high surface area of 696 m2 g−1 exhibits a discharge capacity of as high as 1215 mAh g−1 at 45 mA g−1, excellent rate capability, and outstanding cycling stability with a capacity retention of 663 mAh g−1 at 500 mA g−1 after 1000 cycles. The structure–performance relationships revealed in this work offer a fundamental understanding in the rational design of CMPs anode materials for high performance LIBs. A structure‐design strategy is developed for thiophene‐containing conjugated microporous polymers with extraordinary electrochemical performances as anode materials for lithium‐ion batteries. The polymer of poly(3,3′‐bithiophene) exhibits a high reversible capacity of 1215 mAh g−1 at 45 mA g−1, and outstanding cycling stability with a capacity retention of 663 mAh g−1 at 500 mA g−1 after 1000 cycles.