Aqueous zinc‐ion batteries (ZIBs) are an alternative energy storage system for large‐scale grid applications compared with lithium‐ion batteries, when the low cost, safety, and durability are taken into consideration. However, the reliability of the battery systems always suffers from the serious challenge of the large Zn dendrite formation and “dead Zn,” thus bringing out the inferior cycling stability, and even cell shorting. Herein, a dendrite‐free organic anode, perylene‐3,4,9,10‐tetracarboxylic diimide (PTCDI) polymerized on the surface of reduced graphene oxide (PTCDI/rGO) utilized in ZIBs is reported. Moreover, the theoretical calculations prove the reason for the low redox potential. Due to the protons and zinc ions coparticipant phase transfer mechanism and the high charge transfer capability, the PTCDI/rGO electrode provides superior rate capability (121 mA h g −1 at 5000 mA g −1 , retaining the 95% capacity of that compared with 50 mA g −1 ) and a long cycling life span (96% capacity retention after 1500 cycles at 3000 mA g −1 ). In addition, the proton coparticipation energy storage mechanism of active materials is elucidated by various ex‐situ methods.

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Mn-based cathodes are admittedly the most promising candidate to achieve the practical applications of aqueous zinc-ion batteries because of the high operating voltage and economic benefit. However, the design of Mn-based cathodes still remains challenging because of the vulnerable chemical architecture and strong electrostatic interaction that lead to the inferior reaction kinetics and rapid capacity decay. These intrinsic drawbacks need to be fundamentally addressed by rationally decorating the crystal structure. Herein, an oxygen-defective Mnbased cathode (Oc u -Mn 2 O 3 ) is designed via a doping low-valence Cu-ion strategy. The oxygen defect can modify the internal electric field of the material and enhance the substantial electrostatic stability by compensating for the nonzero dipole moment. With the merits of oxygen deficiency, the Oc u -Mn 2 O 3 electrode exhibits the significant diffusion coefficient in the range from 1 × 10 −6 to 1 × 10 −8 , and good rate performance. In addition, the Oc u -Mn 2 O 3 maintains the highly reversible cyclic stability with the capacity retention of 88% over 600 cycles. The charge storage mechanism is explored as well, illustrating that the oxygen defects can improve the electrochemical active sites of H + insertion, achieving a better charge-storage capacity than Mn 2 O 3 .

To satisfy the demand of high power application, lithium-ion batteries (LIBs) with high power density have gained extensive research effort. The pseudocapacitive storage of LIBs is considered to offer high power density through fast faradic surface redox reactions rather than the slow diffusion-controlled intercalation process. In this work, CuCoS anchored on N/S-doped graphene is in situ synthesized and a typical pseudocapacitive storage behavior is demonstrated when applied in the LIB anode. The pseudocapacitive storage and N/S-doped graphene enable the composite to display a capacity of 453 mA h g after 500 cycles at 2 A g and a ultrahigh rate capability of 328 mA h g at 20 A g. We believe that this work could further promote the research on pseudocapacitive storage in transition-metal sulfides for LIBs.

A hierarchically structured BiS/graphene aerogel composite is constructed that shows excellent sodium storage properties. Specifically, the composite delivers a stable reversible capacity of 397 mA h g at 100 mA g after 50 cycles and 348 mA h g at 1 A g after 120 cycles. Furthermore, even at a high current density of 2 A g, a reversible capacity of 336 mA h g is achieved.