Zinc-bromine flow batteries (ZBFBs) are suitable for large-scale stationary energy storage applications due to their scalability, flexibility, safety, and sustainability [1, 2]. However, the ZBFBs' efficiency is compromised by the heavy accessories and pumps involved in flowing electrolytes on the electrode surface [3]. Because of their heavy weight and other accessories, ZBFBs can only be used for large energy storage systems. Further research is required to expand the application fields of the small-scale static zinc-bromine battery, including portable applications. Therefore, we proposed an innovative cylindrical cell design for a static zinc-bromine battery with a non-flowing liquid electrolyte that offers substantial improvements over existing zinc-bromine flow battery technology. This design aims to enhance coulombic efficiency and energy density, particularly targeting portable applications such as electric vehicles and E-bikes. Our battery configuration involves electrodes (carbon felt and carbon sponge) separated by a microporous separator for ionic migration. The liquid electrolyte, comprising zinc bromide, zinc chloride, potassium chloride, and 1-ethyl-1-methyl pyrrolidinium bromide, facilitates the electrochemical reaction. The battery's electrochemical process involves the plating of zinc ions at the anode and the formation of a bromine complex at the cathode during charging, with reverse reactions during discharge. The entire proposed static battery configuration is made of recyclable Polytetrafluoroethylene (PTFE) polymer, ensuring environmental sustainability. The anode comprises highly conductive graphene-coated carbon felt, while the cathode employs a graphene-coated high-surface-area carbon fiber sponge. Here, we aim to provide more details on the manufacturing methods for the assembly, emphasizing slurry preparation, electrode modification, and electrolyte concentration to achieve enhanced battery performance. With 96 % coulombic efficiency and stable cyclability, the present technology outperforms the existing commercial zinc-bromine battery. Comparative analyses with conventional zinc-bromine flow batteries highlight the advantages of this static battery, including its compactness, reduced weight, and potential for higher energy density. This research represents a significant step towards developing static zinc-bromine batteries suitable for widespread use in portable applications, surpassing the limitations of current zinc-bromine battery technologies.
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