A New Insight into Ultrastable Zn Metal Batteries Enabled by In Situ Built Multifunctional Metallic Interphase

Abstract

Dendrite growth and parasitic side reactions are thorny issues that seriously damage the anode-electrolyte interface during Zn plating/stripping process, leading to uncontrollable Zn deposition and restraining application of aqueous Zn-ion batteries (AZIBs). Here, a unique facile strategy to in situ build indium (In) metal interphase on the Zn anode is first proposed. The combination of experimental and theoretical investigations demonstrate that such metallic interphase prevents the hydrogen evolution reaction (HER) and Zn corrosion, and guides preferential growth along the Zn(002) plane to achieve smooth Zn deposition. As a result, the modified Zn anodes achieve the ultrahigh cumulative capacities of 5600 and 5000 mAh cm −2 at the high current densities of 2 and 5 mA cm −2 , respectively, demonstrating an ultrastable plating/stripping behavior. More encouragingly, the rate performance and cyclic stability of the Zn-V 2 O 5 battery with the electrolyte additive can still deliver a specific capacity of 383.6 mAh g −1 after 5000 cycles at the high current density of 5 A g −1 . The strategy presented here as well as the in-depth understanding of modified mechanism can not only provide an effective solution to address the Zn anode concerns, but also deepen the understanding of AZIBs.

Issues and Opportunities Facing Aqueous Mn2+/MnO2‐based Batteries

“…Electrolyte additives are the mostly employed strategies on electrolyte in Mn 2 + /MnO 2 -based batteries, [19,20] of which the added ions could have catalysis effects on the Mn 2 + /MnO 2 reaction or directly enter into the crystal lattice of deposited MnO 2 and enhance the electronic conductivity. Besides the other functional additives such as redox mediators, electrolyte additives may also contribute to the protective coatings on the anode to address the issues of acidic corrosion, [36] H 2 evolution, [37] dendrites, [38] and so on. Besides, the hydrogel electrolytes were also applied in Mn 2 + / MnO 2 -based batteries, as it could achieve decoupled electrolyte without selective ion-exchange membrane in spite of large overpotential.…”

“…A potential approach of anode-coating might be impactful in anode protection, which can derive from the electrolyte and pre-treated process (Figure 8c), as already mentioned above. [36] Besides, other Zn 2 + (H + ) intercalation-type and conversion-type anodes featuring acid-resistant property may also be matched with Mn 2 + /MnO 2 reaction (Figure 8e). [45]…”

Recent progress, mechanisms, and perspectives for crystal and interface chemistry applying to the Zn metal anodes in aqueous zinc‐ion batteries

“…82 Therefore, new methods and devices should be developed to form a dense and uniform interface with long service life. 81,88,117 2. Based on the high electric charge as well as the big radius of Zn 2+ , the problem might be caused for the high diffusion energy barrier.…”

“…At the same time, unlike other composites, the complex reinforcement pretreatment process is eliminated and the preparation process is simplified 82 . Therefore, new methods and devices should be developed to form a dense and uniform interface with long service life 81,88,117 Based on the high electric charge as well as the big radius of Zn 2+ , the problem might be caused for the high diffusion energy barrier.…”

“…At the same time, unlike other composites, the complex reinforcement pretreatment process is eliminated and the preparation process is simplified 82 . Therefore, new methods and devices should be developed to form a dense and uniform interface with long service life 81,88,117 …”