Hydrogen Bond Networks Stabilized High‐Capacity Organic Cathode for Lithium‐Ion Batteries

High‐capacity small organic materials are plagued by their high solubility. Here we proposed constructing hydrogen bond networks (HBN) via intermolecular hydrogen bonds to suppress the solubility of active material. The illustrated 2, 7‐ diamino‐4, 5, 9, 10‐tetraone (PTO‐NH2) molecule with intermolecular hydrogen (H) bond between O in −C=O and H in −NH2, which make PTO‐NH2 presents transverse two‐dimensional extension and longitudinal π–π stacking structure. In situ Fourier transform infrared spectroscopy (FTIR) has tracked the reversible evolution of H‐bonds, further confirming the existence of HBN structure can stabilize the intermediate 2‐electron reaction state. Therefore, PTO‐NH2 with HBN structure has higher active site utilization (95 %), better cycle stability and rate performance. This study uncovers the H‐bond effect and evolution during the electrochemical process and provides a strategy for materials design. Herein, hydrogen‐bond chemistry in 2, 7‐ diamino‐4, 5, 9, 10‐tetraone (PTO‐NH2) crystal structure is applied to inhibit the dissolution of small organic materials, which enables Li//PTO‐NH2 battery with excellent cycling stability.