Recent Advances in Polymer Electrolytes for Zinc Ion Batteries: Mechanisms, Properties, and Perspectives

Abstract

Aqueous rechargeable zinc ion batteries (ZIBs) have been deemed to be possible candidates for large‐scale energy storage due to their ecoefficiency, substantial reserve, safety, and low cost. However, the challenges inherent in aqueous electrolytes, such as water splitting reactions, water evaporation, and liquid leakage, have greatly hindered their development in energy storage. Fortunately, polymer electrolytes would be able to overcome the abovementioned challenges. Moreover, the flexible properties of polymer electrolytes can facilitate their future application in wearable electronics. Recently, increasing attention has been attracted to the polymer electrolyte‐based zinc ion batteries. However, the development of polymer electrolytes for ZIBs is still in the early stages due to numerous challenges. Therefore, substantial research effort is required to overcome the challenges of polymer electrolyte‐based ZIBs. In this review, the current progress in developing polymer electrolytes, including solid polymer electrolytes, gel polymer electrolytes, and hybrid polymer electrolytes, as well as the interactions between electrodes and polymer electrolytes for ZIBs is comprehensively reviewed, analyzed, and discussed in terms of their synthesis, characterization, and performance validation. To facilitate further research and development of polymer electrolytes for ZIBs, the relevant challenges are summarized and analyzed, and some underlying approaches to overcome these challenges are also proposed.

Dendrites issues and advances in Zn anode for aqueous rechargeable Zn‐based batteries

“…Taking solid state electrolyte (SSE) as an example, the SSEs will provide physical shielding with high mechanical strength and avoid the parasitic reactions occurred in the aqueous counterpart 84 . Normally, SSEs including solid polymer electrolytes (SPEs) and inorganic solid electrolytes (ISEs).…”

Rechargeable Aqueous Zinc‐Ion Batteries with Mild Electrolytes: A Comprehensive Review

“…In this section, we will focus on some important progress on this issue. One can also refer to Lu's [5] and Xia's [225] impressive reviews for more details.…”

Zinc based micro‐electrochemical energy storage devices: Present status and future perspective

“…Besides, the “water‐in‐salt” electrolytes, 125 characteristic of retarded oxygen and hydrogen evolution by the excessively concentrated salt solution, is a highly competitive choice to widen the working voltage window of the aqueous electrolyte on the promise of high safety. In the “water‐in‐salt” electrolyte, the zinc ion hydration could be limited by the high concentration of Li + , Na + , and Al 3 + , 127 which could impede the side reaction of hydrogen evolution reaction. Furthermore, the effective additives, 118,127 such as special polymers, organic molecules and metal ions of Bi 3+ and Pd 2+ , could be considered as one of the key knacks for the zinc dendrites suppression in the improvement of long‐term cyclability, high energy density and high safety of zinc‐based MESDs.…”

“…In the “water‐in‐salt” electrolyte, the zinc ion hydration could be limited by the high concentration of Li + , Na + , and Al 3 + , 127 which could impede the side reaction of hydrogen evolution reaction. Furthermore, the effective additives, 118,127 such as special polymers, organic molecules and metal ions of Bi 3+ and Pd 2+ , could be considered as one of the key knacks for the zinc dendrites suppression in the improvement of long‐term cyclability, high energy density and high safety of zinc‐based MESDs.…”

“…Unique electrode design is of great importance for realizing high energy density without sacrificing the flexibility, such as self‐supporting electrodes, honeycomb‐patterned current collector, spine‐like electrode with the hard component for energy storage and the soft component for flexibility provider. The third strategy is to develop high voltage electrolytes 127 . Especially, all‐solid‐state electrolytes with high voltage, mechanical robustness, high ionic conductivity, and small electrode/electrolyte interface resistance are promising for next‐generation zinc‐based MESDs.…”