Recent advances in the hybrid cathode for rechargeable zinc-bromine redox batteries

Rechargeable metal-bromine batteries have emerged as promising candidates to develop competitive, cost-effective, high-energy-density energy storage systems. The general configuration of a metal-bromine battery includes a metal anode and a bromine cathode. The emergence of zinc-bromine redox batteries (ZBRBs) is attributed to the earth's abundance of zinc, the cost-effectiveness of the active materials, and the high theoretical energy density. Recent advancements have highlighted using bromides (Br-, Br2, and Brn- (n=3, 5, 7…)) entrapping materials for the cathode to enhance the Br-/Br2 redox reaction and inhibit the Br2 diffusion in the ZBRBs. This review aims to explore the various arrangements and insights into bromides-entrapping-based cathodes recently reported. Finally, we share perspectives on the remaining challenges and prospects for the ZBRBs.