Investigation of Capacity Increase in Schiff-Base Networks as the Organic Anode for Lithium-Ion Batteries

Schiff-base polymers are synthesized by the solvothermal method using melamine as the raw material, and their performances as anode materials for lithium-ion batteries are tested. The results show that the capacity of the battery increases at different degrees after cycling at different current densities. The specific charge capacity increases from 144 to 756 mA h g–1 at a current density of 0.5 A g–1 and from 138 to 461 mA h g–1 at a current density of 1 A g–1 after 1000 cycles. The experimental analysis and theoretical calculation show that the increase of capacity of the Schiff-base polymer during cycling is due to the realization of superlithiation with the benzene ring as the lithium storage center. By studying the interaction between the material structure and electrochemical performance, the lithium storage mechanism of the triazine Schiff-base polymer is explored, which provides guidance for the development of high-performance organic cathode materials for lithium-ion batteries.