Current status and technical challenges of electrolytes in zinc–air batteries: An in-depth review

Abstract

In the past few years, there has been a growing level of interest in the research and development of energy storage systems such as batteries. This is a direct consequence of the soaring rise in global energy demand across various commercial and industrial sectors. Lithium ion batteries have set out a feasible horizon for widespread deployment as small-scale energy storage devices due to their high efficiency and cyclability. However, the availability and cost of lithium have limited the commercial deployment of large-scale systems. On the other hand, zinc-air batteries have demonstrated comparable efficiencies and have been reported to be suitable replacements for lithium batteries in large-scale applications. Nevertheless, more research has been undertaken to address the issues associated with the cycling processes of these batteries. Secondary zinc-air batteries are yet to be commercially proven feasible due to the low charge/discharge cycle life of electrodes. The main problems of secondary alkaline zinc-air batteries are dendritic growth resulting in an alternation of morphology and structure, self-dissolution and the consequent occurrence of hydrogen evolution reactions. However, by and large, inefficient electrolytes are the main culprits responsible for the reduced performance of zinc-air batteries. Therefore, a comprehensive review of current advancements in the development of suitable electrolytes to promote zinc-air batteries towards commercial application will provide a perspective for future rechargeable zinc-air batteries. In this in-depth review, the effects of the types of electrolytes and their properties on the electrochemical 2 performance of Zn anode have been discussed. A demonstration of the current research status and challenges set upon the large-scale deployment of zinc-air batteries will facilitate the educated steering of future research directions in this critically important realm.

Advances in Zeolite Imidazolate Frameworks (ZIFs) Derived Bifunctional Oxygen Electrocatalysts and Their Application in Zinc–Air Batteries

“…Adapted with permission. [ 28 ] Copyright 2021, Elsevier Ltd. b) Schematic illustration of performance–limiting issues: (i) dendrite formation, (ii) change of shape, (iii) passivation, and (iv) HER. Reproduced with permission, [ 29 ] Copyright 2016, WILEY VCH.…”

“…Figure 4. a) Pourbaix diagram for zinc-water in electrolyte system as a function of pH in aqueous solution.Adapted with permission [28]. Copyright 2021, Elsevier Ltd. b) Schematic illustration of performance-limiting issues: (i) dendrite formation, (ii) change of shape, (iii) passivation, and (iv) HER.…”

Critical review on development of magnesium alloy as anode inMg‐Airfuel cell and additives in electrolyte

“…However, insufficient studies on the development of suitable electrolyte and influencing factors, such as its composition, delayed the erudite understanding of the matter despite the cell discharge potential, rechargeability, and cell performance having direct implications on the electrolyte. An apt electrolyte should possess high ionic conductivity (>10 −4 S/cm) and low electronic conductivity (<10 −10 S/cm), high chemical stability, low cost and be non‐hazardous to humans and the environment 104 . In general, aqueous electrolytes, such as alkaline solutions, are typically employed owing to the desirable ionic conductivity of cation ions, such as K + , Li + , Na + , and Mg 2+ ; in addition, the development of new electrolytes is scarce.…”

Synthesis of a novel Sr2TiMnO6 double perovskite electrocatalyst for rechargeable zinc–air batteries

“…Adding gel to an aqueous electrolyte increases viscosity, eliminating leakage and leading in the suspension of zinc powder. 53 The zinc-air cell was developed using a zinc foil as the anode, an active perovskite catalyst containing nickel foam as cathode, and 6 M KOH and 0.2 M Zinc Acetate soaked in PVA as an electrolyte, as shown in Figure 6A. Further, Figure 6B interprets the galvanodynamic plot of current density versus voltage polarization for the rechargeable zincair battery cell.…”