A new design strategy for the high-performance organic cathode-active materials of lithium-ion batteries is presented, which involves the assembly of redox-active organic molecules with a crystalline porous structure.

Three porous disulfide‐ligand‐containing metal–organic frameworks (DS‐MOFs) and two nonporous coordination polymers with disulfide ligands (DS‐CPs) with various structural dimensionalities were used as cathode active materials in lithium batteries. Charge/discharge performance examinations revealed that only porous DS‐MOF‐based batteries exhibited significant capacities close to the theoretical values, which was ascribed to the insertion of electrolyte ions into the DS‐MOFs. The insolubility of porous 3 D DS‐MOFs in the electrolyte resulted in cycling performances superior to that of their 1 D and 2 D porous counterparts. Battery reactions were probed by instrumental analyses. The dual redox reactions of metal ions and disulfide ligands in the MOFs resulted in higher capacities, and the presence of reversible electrochemically dynamic S−S bonds stabilized the cycling performance. Thus, the strategy of S−S moiety trapping in MOFs and the obtained correlation between the structural features and battery performance could contribute to the design of high‐performance MOF‐based batteries and the practical realization of Li‐S batteries.

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Double [5]­helicenes possessing two tetracoordinated boron atoms at the ring junctions were synthesized from glycine anhydride in three steps. The helicene with fluorine substituents on the boron atoms was employed as a cathode active material in a lithium battery to demonstrate moderate performance in the 1.8–3.5 V range with more than 63 mAh g–1 discharge capacity for 20 cycles and high Coulombic efficiency of over 90%.

The rapid evolution of electrical devices and the increasing demand for the supply of sustainable energy necessitate the development of high-performance energy storage systems such as rechargeable and redox flow batteries. However, these batteries typically contain inorganic active materials, which exhibit several critical drawbacks hindering further development. In this regard, azo compounds are promising alternatives, offering the benefits of fast kinetics, multi-electron redox reactions, and tunable (via structural adjustment) battery performance. Herein, we review the use of azo compounds as the active materials of rechargeable and redox flow batteries, discuss certain aspects of material design and electrochemical reaction mechanisms, and summarize the corresponding perspectives and research directions to facilitate further progress in this field.