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

Abstract

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.