Morphological effect of waxberry-like superstructured carbon enabling high-performance aqueous zinc-ion battery with prolonged cyclability and reliable operability in cold environment

The practical adoption of aqueous energy storage devices hinges on advancing high energy density, long cycle life, and environmental tolerance, which concentrates on the rapid transport of multivalent electrolyte ions within electrodes. Aiming to address the limitations of traditional carbon electrodes, we proposed the morphological modulation of bio-derived superstructured carbon. Waxberry-like superstructured carbon (WSCC) with interconnected surface open-pore and internal gradient channels was constructed by regulating the hydrophilicity of the hydrophobic part in the carbon precursor molecules. After loading MnO 2 and Zn on WSCC, waxberry-like cathode and anode for aqueous zinc-ion batteries (AZIBs) were produced, both featuring the waxberry-like morphology and highly effective porosity matching Zn 2+ . Benefiting from the morphology effect of WSCC, the transport of Zn 2+ was switched from inter-particle-type to interfacial-type within the electrodes, enhancing transport rate and accessibility. The assembled AZIBs exhibited a high energy density of 367.13 Wh kg −1 . Meanwhile, the waxberry-like morphology minimized the nucleation barrier and altered zinc dendrite growth direction to delay the deterioration of AZIBs. Therefore, excellent cycling stability with capacity retention of 97 % was displayed up to 4,000 cycles, a significant improvement of 60 % over the cycle numbers of bare Zn. Moreover, the AZIBs showed superior low-temperature performance and reliable operability due to the unique morphological effect of WSCC, exhibiting a specific capacity of 164.67 mAh g −1 at −20 °C and stable cyclability between −20 and 20 °C over three cycles. The bio-based high-performance AZIBs combine cycling stability and low-temperature tolerance while meeting the demands of scalability and sustainability.