Zinc-bromine flow batteries (ZBFBs) offer great potential for large-scale energy storage owing to the inherent high energy density and low cost. However, practical applications of this technology are hindered by low power density and short cycle life, mainly due to large polarization and non-uniform zinc deposition.
Zinc–bromine flow batteries have shown promise in their long cycle life with minimal capacity fade, but no single battery type has met all the requirements for successful ESS implementation. Achieving a balance between the cost, lifetime and performance of ESSs can make them economically viable for different applications.
Thermal treatment on electrode further increases the energy efficiency to 81.8%. The battery can be operated at a high current density of up to 80 mA cm −2. The zinc bromine flow battery (ZBFB) is regarded as one of the most promising candidates for large-scale energy storage attributed to its high energy density and low cost.
Zinc–bromine rechargeable batteries are a promising candidate for stationary energy storage applications due to their non-flammable electrolyte, high cycle life, high energy density and low material cost. Different structures of ZBRBs have been proposed and developed over time, from static (non-flow) to flowing electrolytes.
Static non-flow zinc–bromine batteries are rechargeable batteries that do not require flowing electrolytes and therefore do not need a complex flow system as shown in Fig. 1 a. Compared to current alternatives, this makes them more straightforward and more cost-effective, with lower maintenance requirements.
Biswas et al. also reported a membrane-free zinc bromine static battery (Figure 11D). The anode was placed near the aqueous region of the electrolyte to avoid self-discharge. This membrane-free design saw cycling stability for over 1000 cycles with high coulombic efficiency (90%) and energy efficiency (60%).