A Conjugated Coordination Polymer with Benzoquinone as Electrode Material for All Organic Symmetric Lithium‐ion Batteries

Carbonyl rich conjugated polymer electrode materials for lithium‐ion batteries possessed the advantages of strong molecular design ability, abundance and high theoretical capacity. In this work, a Co2+ coordinated conjugated polymer using 2,3,5,6‐tetraamino‐p‐benzoquinone (TABQ) as building block was constructed and developed as electrode material for all organic symmetric lithium‐ion batteries, outputting a specific capacity of over 100 mAh g‐1 after 50 cycles at 50 mA g‐1. Performances of Co‐TABQ in half cells were explored. The Co‐TABQ cathode delivered a capacity of 133.3 mAh g‐1 after 150 cycles at 20 mA g‐1. When cycled at higher current density of 500 mA g‐1, the capacity gradually increased to 109.4 mAh g‐1 after 4000 cycles. The Co‐TABQ anode displayed a stable capacity of 568.6 mAh g‐1 at 1 A g‐1. The charge transfer within the electrode was greatly reduced due to the metallic centers in the extended conjugated skeleton, and the reversible Li+ storage was achieved by the active C=O and imine groups. This work showed the great potential of metal mediated conjugated polymer in Lithium‐ion batteries.