our knowledge, the rate capability and cycling stability of CP2 is one of the best reported for organic Li-ion batteries. Compared to many other well-known cathode materials for Li-ion batteries, such as inorganic LiCoO2 (140 mAh g -1 ), TEMPO (radical) functionalized polymethcarylate (PTMA, 111 mAh g -1 ), 8 polyanthraquinone (263 mAh g -1 ) , poly(chalcogenoviologen)s (463 mAh g -1 at 0.5 A g - 1 ), and other previously reported bio-derived polymeric cathode materials (< 150 mAh g -1 ), our polymer provides among the highest specific capacity, making this current system highly desirable as an organic cathode material for lithium-ion battery applications. . Furthermore, to better understand the Li + diffusion process, the diffusion coefficients (DLi + ) of the four electrodes were calculated from the Warburg region (see the SI for details). The DLi + values of 1, 2, CP1, and CP2 were calculated to be 6.64×10 -14 cm 2 S -1 , 8.54×10 -14 cm 2 S -1 , 1.42×10 -13 , and 3.12×10 , respectively. The highest DLi + value of CP2 indicates faster lithium-ion diffusivity, consistent with the battery test data.