Comprehensive review onzinc‐ionbattery anode: Challenges and strategies

Abstract

Zinc‐ion batteries (ZIBs) have been extensively investigated and discussed as promising energy storage devices in recent years owing to their low cost, high energy density, inherent safety, and low environmental impact. Nevertheless, several challenges remain that need to be prioritized before realizing the widespread application of ZIBs. In particular, the development of zinc anodes has been hindered by many challenges, such as inevitable zinc dendrites, corrosion passivation, and the hydrogen evolution reaction (HER), which have severely limited the practical application of high‐performance ZIBs. This review starts with a systematic discussion of the origins of zinc dendrites, corrosion passivation, and the HER, as well as their effects on battery performance. Subsequently, we discuss solutions to the above problems to protect the zinc anode, including the improvement of zinc anode materials, modification of the anode–electrolyte interface, and optimization of the electrolyte. In particular, this review emphasizes design strategies to protect zinc anodes from an integrated perspective with broad interest rather than a view with limited focus. In the final section, comments and perspectives are provided for the future design of high‐performance zinc anodes.

Emerging strategies for steering orientational deposition toward high-performance Zn metal anodes

“…However, under practical conditions, polarization of the Zn anode during the charging process readily reduces the evolution potential of H 2 , where the HER could be limited to some extent yet still inevitable owing to inter-granular corrosion. 55 A recent study by Yang et al demonstrated that H 2 stems not from free water molecules but mainly from the deprotonation process of hydrated Zn. 56 Once the H 2 is liberated (eqn (2)), the internal pressure of the battery increases, followed by possible volume expansion and electrolyte leakage.…”

Textured Na2V6O16·3H2O Cathode Tuned via Crystal Engineering Endows Aqueous Zn-Ion Batteries with High Rate Capability and Adequate Lifespan

“…Nevertheless, the large-scale application of ZIBs in smart grids is mainly hindered by cathode materials that deliver relatively low capacity. , Since alpha-manganese-dioxide (α-MnO 2 ) was reported by Kang et al a decade ago, polymorphous MnO 2 , − Prussian blue analogs, − as well as vanadium-based materials , have been subsequently explored as cathode materials for ZIBs. Vanadium-based materials are expected to exhibit higher capacity with excellent stability for commercialization of ZIBs due to the variable valences, ranging from +5 to +2, and the open skeleton with the changeable structure for the V–O coordination polyhedron. , As a typical representative of vanadium-based materials, sodium vanadate stands out from the crowd with its diverse crystal structures and excellent electrochemical properties .…”

Improved Interface Stability and Zinc‐Ions Distribution Achieved by Functional Protective Layer Containing Abundant Oxygen Sites and Regular Channels for Long‐Life Zinc‐Metal Anodes

“…These by-products with poor transference of Zn ions would be generated on the corrosion process due to the local pH elevation caused by competitive HER. [43] In contrast with Zn@FPL, it could be evidently viewed that numerous blocks (by-product) were unevenly dispersed on the bare Zn, indicating the relatively concentrated distribution of Zn ions and more severe interfacial corrosion. The structure information of electrodes after the immersion procedure was also determined.…”

“…Interestingly, although encountering some influences of electrolyte, electrode surface of Zn@FPL after removing the protective layer still maintained the comparatively flat state with slight wrinkle, which should be the by‐product of Zn 4 SO 4 (OH) 6 ⋅ 3H 2 O. These by‐products with poor transference of Zn ions would be generated on the corrosion process due to the local pH elevation caused by competitive HER [43] . In contrast with Zn@FPL, it could be evidently viewed that numerous blocks (by‐product) were unevenly dispersed on the bare Zn, indicating the relatively concentrated distribution of Zn ions and more severe interfacial corrosion.…”