Zinc dendrite growth negatively affects zinc–bromine flow battery (ZBB) performance by causing membrane damage, inducing self-discharge. Herein, in a ZBB, a conventional polymer mesh was replaced with a titanium-based mesh interlayer; this provided additional abundant active sites for the Zn2+/Zn redox reaction and well-developed electrolyte flow channels, which resulted in improved reaction kinetics and suppressed Zn dendrite growth. Compared with a ZBB cell comprising a conventional polymer mesh and a carbon-based electrode, the ZBB cell using the titanium mesh interlayer and a carbon-based electrode showed significantly reduced frequency of the refreshing process, which occurs at regular cycling intervals during practical use for removing residual zinc dendrites in ZBB; also, the average energy efficiency at a current density of 40 mA cm−2 increased by 38.5%. Moreover, the modified ZBB cell exhibited higher energy efficiency at a high current density of 80 mA cm−2, which is an improvement of 14.7% than in case of the contemporary polymer mesh. Consequently, this study can provide helpful insights for new anode side structures including spacer mesh for developing high-performance ZBBs.

Redox flow batteries (RFBs) are regarded as one of the most attractive systems for large-scale electrochemical energy storage because of simple design, good scalability, and good cycle efficiency. Among various flow batteries, zinc-bromine flow battery (ZBB) has a lot of benefits due to the high solubility of Zn, which enables high practical energy density of around 65~75 Wh/kg. Additionally, low cost which comes from the abundance of zinc compounds has thrown light on the popularization of ZBB. Until now, however, widespread application of ZBB has not been realized due ot its drawback. Zinc dendrite growth has negative effect on Zn/Br performance because of membrane damage, which allows self-discharge. Therefore, to get rid of dendrite formation after prolonged cycling, zinc dendrite strip cycling should run in the process of cycling. In this work, we introduced Ti-mesh interlayer on the negative electrode to suppress the formation of zinc dendrite. We compared the effect of mesh interlayer using strip cycling during cycling.