Zinc-ion batteries built on water-based electrolytes featuring compelling price-points, competitive performance, and enhanced safety represent advanced energy storage chemistry as a promising alternative to current lithium-ion battery systems. Attempts to develop rechargeable aqueous zinc-ion batteries (ZIBs) can be traced to as early as the 1980s; however, since 2015, the research activity in this field has surged throughout the world. Despite the achievements made in exploring electrode materials so far, significant challenges remain at the material level and even on the whole aqueous ZIBs system, leading to the failure of ZIBs to meet commercial requirements. This review aims to discuss how to pave the way for developing aqueous ZIBs. The current research efforts related to aqueous ZIBs electrode materials and electrolytes are summarized, including an analysis of the problems encountered in both cathode/anode materials and electrolyte optimization. Some concerns and feasible solutions for achieving practical aqueous ZIBs are discussed in detail. We would like to point out that merely improving the electrode materials is not enough; synergistic optimization strategies toward the whole battery system are also deeply needed. Finally, some perspectives are provided on the subsequent optimization design for further research efforts in the aqueous ZIB field.

Issues and opportunities facing aqueous zinc-ion batteries

Aqueous zinc ion batteries (ZIBs) are truly promising contenders for the future large-scale electrical energy storage applications due to their cost-effectiveness, environmental friendliness, intri...

Active Materials for Aqueous Zinc Ion Batteries: Synthesis, Crystal Structure, Morphology, and Electrochemistry

Rechargeable sodium-ion batteries (SIBs), as the most promising alternative to commercial lithium-ion batteries, have received tremendous attention during the last decade. Among all the anode materials for SIBs, metal sulfides/selenides (MXs) have shown inspiring results because of their versatile material species and high theoretical capacity. They suffer from large volume expansion, however, which leads to bad cycling performance. Thus, methods such as carbon modification, nanosize design, electrolyte optimization, and cut-off voltage control are used to obtain enhanced performance. Here, recent progress on MXs is summarized in terms of arranging the crystal structure, synthesis methods, electrochemical performance, mechanisms, and kinetics. Challenges are presented and effective ways to solve the problems are proposed, and a perspective for future material design is also given. It is hoped that light is shed on the development of MXs to help finally find applications for next-generation rechargeable batteries.

Advances and Challenges in Metal Sulfides/Selenides for Next-Generation Rechargeable Sodium-Ion Batteries.

The zinc metal is recognized as one of the most promising anodes for Zn-based batteries in an energy-storage system. However, the deposition and transfer of bivalent Zn2+ into the host structure suffer from sluggish kinetics accompanying the side-reactions at the interface. Herein, we report a new class of Zn anodes modified by a three-dimensional (3D) nanoporous ZnO architecture coating on a Zn plate (designated as Zn@ZnO-3D) prepared by in situ Zn(OH)42− deposition onto the surface. This novel structure has been proven to accelerate the kinetics of Zn2+ transfer and deposition via the electrostatic attraction toward Zn2+ rather than the hydrated one in the electrical double layer. As a consequence, it achieves an average 99.55% Zn utilization and long-time stability for 1000 cycles. Meanwhile, the Zn@ZnO-3D/MnO2 cell shows no capacity fading after 500 cycles at 0.5 A g−1 with a specific capacity of 212.9 mA h g−1. We believe that the mechanistic insight into the kinetics and thermodynamic properties of the Zn metal and the understanding of structure–interface–function relationships are very useful for other metal anodes in aqueous systems.

Manipulating the ion-transfer kinetics and interface stability for high-performance zinc metal anodes

Aqueous zinc-ion batteries have rapidly developed recently as promising energy storage devices in large-scale energy storage systems owing to their low cost and high safety. Research on suppressing zinc dendrite growth has meanwhile attracted widespread attention to improve the lifespan and reversibility of batteries. Herein, design methods for dendrite-free zinc anodes and their internal mechanisms are reviewed from the perspective of optimizing the host-zinc interface and the zinc-electrolyte interface. Furthermore, a design strategy is proposed to homogenize zinc deposition by regulating the interfacial electric field and ion distribution during zinc nucleation and growth. This Minireview can offer potential directions for the rational design of dendrite-free zinc anodes employed in aqueous zinc-ion batteries.

Interfacial design of dendrite‐free zinc anodes for aqueous zinc‐ion batteries

A Sieve-Functional and Uniform-Porous Kaolin Layer toward Stable Zinc Metal Anode

Spatially homogeneous copper foam as surface dendrite-free host for zinc metal anode

Metal zinc, with the advantages of low cost, low redox potential, and high capacity, is an ideal anode for aqueous zinc-ion batteries. Nonetheless, the inferior plating/stripping Coulombic efficien...

Homogeneous Deposition of Zinc on Three-Dimensional Porous Copper Foam as a Superior Zinc Metal Anode

Presently, considerable attention has been paid to the Fe-based dichalcogenides as anode materials for sodium ion batteries (SIBs) due to their abundant resources, chemical stability, and high theoretical capacity. In this paper, we make nanooctahedra particles assembled FeSe2 microspheres embedded into sulfur-doped reduced graphene oxide sheets through a one-step hydrothermal reduction route, in which the reduction of graphene oxide, the doping of sulfur atoms, and the preparation of FeSe2/sulfur-doped reduced graphene oxide (FeSe2/SG) composites are realized at the same time. When serving as anodes for SIBs, the FeSe2/SG electrode can display superior electrochemical performances with a large reversible capacity of 447.5 mA h g–1 at 0.5 A g–1 and an excellent rate capability of 383.3 and 277.5 mA h g–1 at the current density of 2.0 and 5.0 A g–1, which could be attributed to the introduction of sulfur atoms into the reduced graphene oxide structure and the synergistic effect between microsphere-like FeS...

Nanooctahedra Particles Assembled FeSe2 Microspheres Embedded into Sulfur-Doped Reduced Graphene Oxide Sheets As a Promising Anode for Sodium Ion Batteries

Xiaodong Shi

Papers

A Sieve-Functional and Uniform-Porous Kaolin Layer toward Stable Zinc Metal Anode

Spatially homogeneous copper foam as surface dendrite-free host for zinc metal anode

Homogeneous Deposition of Zinc on Three-Dimensional Porous Copper Foam as a Superior Zinc Metal Anode

Nanooctahedra Particles Assembled FeSe2 Microspheres Embedded into Sulfur-Doped Reduced Graphene Oxide Sheets As a Promising Anode for Sodium Ion Batteries

Synthesis of core-shell NiSe/C nanospheres as anodes for lithium and sodium storage