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Redox‐active organics based on a multi‐electron mechanism are of great interest in battery electrode materials as they are capable of delivering high capacity per molecular weight. However, most of such organics shows huge voltage gap that is inherited from their stepwise redox reactions occurring in the same conjugated redox moiety. This study focuses on the voltage tailoring of polymeric dihydrophenazine derivative, which shows high specific capacity as a cathode electrode material and decent cycling stability, but suffers huge voltage gap of ca. 0.8 V. We demonstrate a strategy to modify the voltage gap of dihydrophenazine derivatives through the incorporation of functional groups with different electron affinity near the redox moiety. The as‐designed dihydrophenazine derivatives are further copolymerized to yield a polymeric material with significantly smoothened charge‐discharge profiles and good capacity retention. We further demonstrate through theoretical calculation based on density‐functional theory that the substitute site and types of functional groups are of great importance in voltage tailoring as well as structural stability of the dihydrophenazine derivatives. [ABSTRACT FROM AUTHOR]

Symmetric batteries received an increasing research interest in the past few years because of their simplified fabrication process and reduced manufacturing cost. In this study, we propose the first dual‐ion organic symmetric cell based on a molecular anion of 4,4′‐(phenazine‐5,10‐diyl)dibenzoate. The alkali salt of 4,4′‐(phenazine‐5,10‐diyl)dibenzoate allows a facile transport of cations and large anions, and remains stable in both oxidized and reduced states. The large potential difference between phenazine and benzoate results in a high cell voltage of 2.5 V and an energy density of 127 Wh kg−1 at a current rate of 1 C. The introduction of bipolar organic materials may further consolidate the development of symmetric batteries that are fabricated from abundant elements and environmentally friendly materials. [ABSTRACT FROM AUTHOR]