Manipulation of conjugation to stabilize N redox-active centers for the design of high-voltage organic battery cathode

Organic redox compounds are promising candidates for lithium ion batteries owing to the elemental abundance and structural diversity. However, the low redox potential and chemical bond cleavage/recombination during lithiation/delithiation have significantly limited their practical application. We demonstrate here the manipulation of conjugation to stabilize N redox-active centers in a p-type, two-electron-transfer oligomer of N, N'-diphenyl-5,10-dihydrophenazine as a high-voltage organic battery cathode material, which exhibits high redox potentials of 4.1 and 3.3 V (vs. Li+/Li), good stability, and a galvanometric energy density of ca. 530 Wh kg(-1). The redox active electron localized on the dihydrophenazine unit in this oligomer are believed to contribute to the good electrochemical performances.