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Abstract Aqueous zinc‐ion batteries have been regarded as the most potential candidate to substitute lithium‐ion batteries. However, many serious challenges such as suppressing zinc dendrite growth and undesirable reactions, and achieving fully accepted mechanism also have not been solved. Herein, the commensal composite microspheres with α‐MnO2 nano‐wires and carbon nanotubes were achieved and could effectively suppress ZnSO4·3Zn(OH)2·nH2O rampant crystallization. The electrode assembled with the microspheres delivered a high initial capacity at a current density of 0.05 A g−1 and maintained a significantly prominent capacity retention of 88% over 2500 cycles. Furthermore, a novel energy‐storage mechanism, in which multivalent manganese oxides play a synergistic effect, was comprehensively investigated by the quantitative and qualitative analysis for ZnSO4·3Zn(OH)2·nH2O. The capacity contribution of multivalent manganese oxides and the crystal structure dissection in the transformed processes were completely identified. Therefore, our research could provide a novel strategy for designing improved electrode structure and a comprehensive understanding of the energy storage mechanism of α‐MnO2 cathodes.

Rechargeable aqueous ammonium-ion batteries (AAIBs) have attracted more and more attention in energy storage devices because of great safety and cost-effectiveness, as well as excellent rate capability. Recently, it is the main exploration focus for the further improvement of AAIBs to develop suitable electrode materials. Herein, titanic acid and TiO2 were simply synthesized by the facile co-precipitation approach. Titanic acid showed higher capacity of 104.5 mAh g−1 at the 0.1 A g−1 current density, and higher cyclability with the 91.2% capacity retention cycled 1000 cycles at 1 A g−1. Titanic acid is promising as aqueous ammonium-ion batteries with great stability and capacity. [ABSTRACT FROM AUTHOR]

Uniform Nb 2 O 5 nanospheres/surface-modified graphene (SMG) composites for anode materials in lithium ion batteries were synthesized by hydrothermal method. The microstructure and morphology of composites were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscope techniques. The experimental results showed that Nb 2 O 5 nanospheres were tightly and uniformly grown on the surface of SMG nanosheets. Nb 2 O 5 nanospheres/SMG composites exhibited an impressive reversible capacity of 404.6 mA h g −1 at the current density of 40 mA g −1 after 100 cycles, and an excellent rate capacity of 345.5 mA h g −1 at the current density of 400 mA g −1 . [ABSTRACT FROM AUTHOR]