Toward High Energy Density Aqueous Zinc‐Ion Batteries: Recent Progress and Future Perspectives

Abstract

Aqueous zinc-ion batteries (ZIBs) are promising next-generation battery system which can mitigate the prevailing issues on the conventional lithium-ion batteries. However, insufficient energy density with low operating voltage prevents the practical utilization of the aqueous system. Notably, aqueous ZIBs suffer from electrolyte decomposition due to its narrow electrochemical stability window (ESW) for 1.23 V. Also, studies on cathode active materials that store charge at an elevated voltage region is still in the initial stage. In this perspective, we cover the recent strategies for developing high-voltage aqueous ZIBs. First, electrolyte designs for expanding the ESW of an aqueous electrolyte are introduced based on their characterization, materials, and working mechanisms. Next, we propose the cathode active materials with high-working voltage. Furthermore, studies on zinc anodes are also briefly presented. Lastly, we summarize the as-reported strategies and provide insight for developing future ZIBs.

Improved Strategies for Separators in Zinc‐Ion Batteries

“…[31,33,34] To overcome these problems, various strategies have been proposed, including the modification of traditional GF separators and the development of novel separators. There have been many reviews on ZIBs, [35][36][37][38] but almost none have focused on separators. Herein, we comprehensively review the recent research progress of research on separators in ZIBs based on their functions and roles in ZIBs, including the modification of traditional GF and the development of novel separators (Figure 2).…”

Aqueous Zn−organic batteries: Electrochemistry and design strategies

“…Among various “beyond lithium‐ion” battery technologies, aqueous Zn–ion batteries (AZIBs) have attracted increasing attention due to the high theoretical specific capacity (820 mAh g −1 ), appropriate redox potential (−0.76 V vs. standard hydrogen electrode), cheaper price of Zn metal, and facile manufacturing process. Furthermore, the inherent safety and non‐toxicity of aqueous electrolytes make them particularly appealing for future large‐scale applications 8–15 …”

Hierarchical Carbon Nanosheet Embedded MnOx Cathode for High‐Performance Aqueous Zinc‐Ion Batteries

“…Therefore, development of non‐lithium battery technology with high safety and cost effectiveness is highly desirable [10,11] . In this regard, zinc‐ion batteries (ZIBs) that use nonflammable aqueous electrolytes represent a promising candidate capable of enabling intrinsic safety [12,13] . Moreover, the abundant natural resources and cost effectiveness of Zn exhibit great potential in large‐scale energy storage [14–16] .…”

“…[10,11] In this regard, zinc-ion batteries (ZIBs) that use nonflammable aqueous electrolytes represent a promising candidate capable of enabling intrinsic safety. [12,13] Moreover, the abundant natural resources and cost effectiveness of Zn exhibit great potential in large-scale energy storage. [14][15][16] However, the strong electrostatic interaction between bivalent Zn 2 + and host materials in repeating intercalation/deintercalation process in ZIB, leads to low capacity, serious structural distortion, and capacity decay.…”