High-Performance Li-Organic Batteries Based on Conjugated and Nonconjugated Schiff-Base Polymer Anode Materials

In recent years, organic materials have been increasingly studied as anode materials in lithium-ion batteries (LIBs) due to their remarkable advantages, including abundant raw materials, low prices, diverse structures, and high theoretical capacity. In this paper, three types of aromatic Schiff-base polymer materials have been synthesized and examined as anode materials in LIBs. Among them, the polymer [C₆H₄N = CHC₆H₄CH=N] (TTD-PDA) has a continuous conjugated backbone (label as conjugated polymer), while polymers [(CH₂)₂N=CHC₆H₄CH=N] (TTD-EDA) and [C₆H₄N=CH(CH₂)₃CH=N] (GA-PDA) have discontinuous conjugated back-bones (label as nonconjugated polymer). The organic anodes based on TTD-PDA, TTD-EDA, and GA-PDA for LIBs are discovered to represent high reversible specific capacities of 651, 492, and 416 mAh g^-1 at a current density of 100 mA g^-1 as well as satisfactory rate capabilities with high capacities of 210, 90, and 178 mAh g^-1 and 105, 57, and 122 mAh g^-1 at current densities of 2 and 10 A g^-1, indicating that these Schiff-base polymers are all promising anode materials for LIBs, which broadens the design of organic anode materials with high specific capacity, superior rate performance, and stable cycling stability.