Molecular Design Strategies for High‐Voltage Organic Cathodes

ABSTRACT Organic electrode materials (OEMs) offer promising pathways toward sustainable and high‐performance rechargeable batteries, yet their practical implementation is limited by rigid crystal structures, poor electronic conductivity, and low redox potential. Here, we conduct a systematic molecular‐level investigation of two organic cathodes, phenazine‐1,4,6,9‐tetrone (PzTO) and dithiin‐fused naphthazarin (5,8‐dihydroxy‐1,4‐naphthoquinone) (DNP), through a combined computational and experimental approach. Solution‐phase cyclic voltammetry reveals a substantial redox potential gap between them, with DNP exhibiting a reduction potential ∼500 mV higher than PzTO. This difference becomes more pronounced in solid state measurements, where the first reduction potentials reach ∼3.68 V vs. Li ⁺ /Li for DNP and 3.08 V for PzTO. By dissecting the molecular origins of these trends, we identify two governing features: (i) changes of aromaticity upon reduction (differential aromaticity) and (ii) Li─O coordination number. Density functional theory calculations confirm that these features strongly modulate lithiation free energies. Extending our analysis to a series of hypothetical derivatives of PzTO and DNP, we establish a linear relationship between differential aromaticity and lithiation free energy and show that the introduction of additional Li─O coordination enhances redox potentials. Taken together, these molecular engineering insights offer a mechanistic foundation for rationalizing high‐voltage performance and guiding the design of next‐generation OEMs.