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Polymers with redox activity are one type of promising candidates of cathode materials for aqueous Zn‐ion batteries due to their potential low‐cost, high safe, and renewable features. Unfortunately, suboptimal polymer electrode structure often results in unsatisfactory electrochemical performance. Herein, poly(1,8‐diaminonaphthalene)/active carbon composite electrodes are prepared via nanoconfined in situ electropolymerization within porous active carbon, which have ultrahigh specific surface area (1035.0 m2 g−1) and unique nano‐porous structure, thereby highly enhancing the utilization of the active site up to 91.6%. The as‐prepared cathodes deliver ultrahigh reversible capacity of 479.5 mAh g−1, ultrafast rate capability of up to 60 A g−1 and an ultralong life span of 50,000 cycles. Storage mechanism investigation indicates that the cathode material involves a bipolar‐type behavior. These encouraging results demonstrate that nanoconfined in situ electropolymerization in active carbon is a brand‐new strategy for the design of advanced polymer electrodes for high‐performance aqueous Zn‐organic batteries. [ABSTRACT FROM AUTHOR]

Lithium metal‐graphene host composite is a promising anode material for high‐energy‐density Li battery owing to its three‐dimensional structure, micro‐level controllable thickness and ultrahigh specific capacity. However, we discover that the hydroxyl/carboxyl functional groups in the reduced graphene oxide (rGO) host are likely to be reduced into lithium carbonate composition in the solid‐electrolyte interphase (SEI), which resulted in severe lithium dendrite growth that deteriorate its electrochemical performances. Here, we develop a magnesium anchoring strategy that selectively bond the Mg ion with the hydroxyl/carboxyl groups in rGO host, generating an electrolyte‐derived lithium fluoride‐dominant SEI instead of oxygen groups‐derived, lithium carbonate‐dominant SEI. By anchoring 0.60% of Mg in the rGO host using a facile compositing‐pyrolysis approach, Li dendrite growth in anode can be significantly suppressed, and the cycling stability of Li metal full cells can be prolonged by 200%. These findings give new insight into the mechanism of SEI formation in Li metal anode, and provide a new design strategy for restraining the reduced reaction of hydroxyl/carboxyl groups in graphene to stabilize the composite anode of lithium metal battery. [ABSTRACT FROM AUTHOR]

Organic electrode materials for lithium‐ion batteries have attracted significant attention in recent years. Polymer electrode materials, as compared to small‐molecule electrode materials, have the advantage of poor solubility, which is beneficial for achieving high cycling stability. However, the severe entanglement of polymer chains often leads to difficulties in preparing nanostructured polymer electrodes, which is vital for achieving fast reaction kinetics and high utilization of active sites. This study demonstrates that these problems can be solved by the in situ electropolymerization of electrochemically active monomers in nanopores of ordered mesoporous carbon (CMK‐3), combining the advantages of the nano‐dispersion and nano‐confinement effects of CMK‐3 and the insolubility of the polymer materials. The as‐prepared nanostructured poly(1‐naphthylamine)/CMK‐3 cathode exhibits a high active site utilization of 93.7%, ultrafast rate capability of 60 A g−1 (≈320 C), and an ultralong cycle life of 10000 cycles at room temperature and 45000 cycles at −15 °C. The study herein provides a facile and effective method that can simultaneously solve both the dissolution problem of small‐molecule electrode materials and the inhomogeneous dispersion issue of polymer electrode materials. [ABSTRACT FROM AUTHOR]