Polyimide Containing Tricarbonyl Moiety as an Active Cathode for Rechargeable Li-Ion Batteries

We report studies on polyimide containing tricarbonyl moiety, which derived from the perylene-3,4,9,10-tetracarboxylic dianhydride and 2,6-diaminoanthraquinone compound, as a novel cathode for a lithium battery. The synthesized polyimide have the higher electron affinity and lower ionization potential values compared to the perylene-3,4,9,10-tetracarboxylic dianhydride, resulting in better redox reversibility than perylene-3,4,9,10-tetracarboxylic dianhydride in the lithium-ion battery. The polyimide exhibits remarkable charge-discharge properties with a specific capacity of 128.43 mA h g−1, excellent Coulombic efficiency (100% over 280 cycles) and good rate capability (78% of the capacity at 200 mA g−1 as compared to 20 mA g−1), which results from several combined advantages such as the presence of an additional carbonyl group, a favorable energy level, and improved conductivity. This result implies that electrochemical properties of polyimide with additional carbonyl group can offer new possibilities for the development of efficient all-organic energy storage systems.