Self-crosslinked herringbone dihydrophenazine derivatives for high performance organic batteries

Organic cathode materials are considered as candidates for the next generation batteries due to their predictable high theoretical capacity, structure diversity, design flexibility, potentially sustainable production, low cost, and low carbon footprint. However, compared with traditional inorganic materials, the high-performance organic electrode materials with application potential are still insufficient. The multi-electron active center dihydrophenazine exhibiting high specific capacity with impressive stability and high discharge voltage has attracted increasing attention. Herein, we develop a dihydrophenazine-based self-crosslinked polymer p-PZ as an electrochemical transfer type redox active cathode material. This polymer p-PZ based batteries exhibit excellent integral performances with the charge/discharge potential of 3.1 V–4.2 V (vs. Li+/Li), high discharge specific capacity of 198 mAh g−1 at 0.5C, energy density up to 558 Wh kg−1, and long cycling stability. The crossed herringbone configuration of polymers chain is designed and facilitated to break the face-to-face stacking and form the voids like ion transport channels which would be beneficial for ion diffusion and expected higher charge/discharge rate and power density (up to 2920 Wkg-1 at 10C). Moreover, p-PZ also possessed the potential as a cathode active material for sodium-ion batteries. Our research provides an effective strategy and approach to effectively improve the energy and power density of organic batteries by molecular design.