The aprotic lithium–oxygen (Li–O2) battery has excited huge interest due to it having the highest theoretical energy density among the different types of rechargeable battery. The facile achievement ...of a practical Li–O2 battery has been proven unrealistic, however. The most significant barrier to progress is the limited understanding of the reaction processes occurring in the battery, especially during the charging process on the positive electrode. Thus, understanding the charging mechanism is of crucial importance to enhance the Li–O2 battery performance and lifetime. Here, recent progress in understanding the electrochemistry and chemistry related to charging in Li–O2 batteries is reviewed along with the strategies to address the issues that exist in the charging process at the present stage. The properties of Li2O2 and the mechanisms of Li2O2 oxidation to O2 on charge are discussed comprehensively, as are the accompanied parasitic chemistries, which are considered as the underlying issues hindering the reversibility of Li–O2 batteries. Based on the detailed discussion of the charging mechanism, innovative strategies for addressing the issues for the charging process are discussed in detail. This review has profound implications for both a better understanding of charging chemistry and the development of reliable rechargeable Li–O2 batteries in the future.
Addressing the challenges facing lithium–oxygen (Li–O2) batteries during charging is of great significance for improving the performance of Li–O2 batteries. A fundamental discussion on the science underpinning the charging chemistry of the Li–O2 system and on promising strategies for improving these reactions is presented. The findings have deep implications for the future development of reliable rechargeable Li–O2 batteries.
Prussian blue analogues (PBAs, A2TM(CN)6, A = Li, K, Na; T = Fe, Co, Ni, Mn, Cu, etc.; M = Fe, Mn, Co, etc.) are a large family of materials with an open framework structure. In recent years, they ...have been intensively investigated as active materials in the field of energy conversion and storage, such as for alkaline‐ion batteries (lithium‐ion, LIBs; sodium‐ion, NIB; and potassium‐ion, KIBs), and as electrochemical catalysts. Nevertheless, few review papers have focused on the intrinsic chemical and structural properties of Prussian blue (PB) and its analogues. In this Review, a comprehensive insight into the PBAs in terms of their structural and chemical properties, and the effects of these properties on their materials synthesis and corresponding performance is provided.
This Review provides a comprehensive overview of the latest research progress on Prussian blue analogues (PBAs), including the synthesis methods, structural and chemical properties of PBAs, various applications for these PBAs, and the effects of their structural and chemical properties on material synthesis and applications. Finally, some personal viewpoints on the challenges and outlook for PBAs application are included.
Sodium‐ion batteries (SIBs) have been considered as the most promising candidate for large‐scale energy storage system owing to the economic efficiency resulting from abundant sodium resources, ...superior safety, and similar chemical properties to the commercial lithium‐ion battery. Despite the long period of academic research, how to realize sodium‐ion battery commercialization for market applications is still a great challenge. Thus, from the perspective of future practical application, this review will identify the factors that are restricting commercialization, and evaluate the existing active materials and sodium‐ion‐based full‐cell system. The design and development trends that are needed for SIBs to meet the requirements of practical applications in large‐scale energy storage will also be discussed in detail.
Despite the long period of academic research, it is still a great challenge to realize sodium‐ion battery commercialization for market applications. From the perspective of sodium‐ion battery future practical application, this review will identify the factors that are restricting its commercialization, and evaluate the existing active materials and sodium‐ion‐based full‐cell system.
Iron-based Prussian blue analogs are promising low-cost and easily prepared cathode materials for sodium-ion batteries. Their materials quality and electrochemical performance are heavily reliant on ...the precipitation process. Here we report a controllable precipitation method to synthesize high-performance Prussian blue for sodium-ion storage. Characterization of the nucleation and evolution processes of the highly crystalline Prussian blue microcubes reveals a rhombohedral structure that exhibits high initial Coulombic efficiency, excellent rate performance, and cycling properties. The phase transitions in the as-obtained material are investigated by synchrotron in situ powder X-ray diffraction, which shows highly reversible structural transformations between rhombohedral, cubic, and tetragonal structures upon sodium-ion (de)intercalations. Moreover, the Prussian blue material from a large-scale synthesis process shows stable cycling performance in a pouch full cell over 1000 times. We believe that this work could pave the way for the real application of Prussian blue materials in sodium-ion batteries.
As one of the most competitive candidates for large‐scale energy storage, zinc–air batteries (ZABs) have attracted great attention due to their high theoretical specific energy density, low toxicity, ...high abundance, and high safety. It is highly desirable but still remains a huge challenge, however, to achieve cheap and efficient electrocatalysts to promote their commercialization. Recently, Fe‐based single‐atom and dual‐atom catalysts (SACs and DACs, respectively) have emerged as powerful candidates for ZABs derived from their maximum utilization of atoms, excellent catalytic performance, and low price. In this review, some fundamental concepts in the field of ZABs are presented and the recent progress on the reported Fe‐based SACs and DACs is summarized, mainly focusing on the relationship between structure and performance at the atomic level, with the aim of providing helpful guidelines for future rational designs of efficient electrocatalysts with atomically dispersed active sites. Finally, the great advantages and future challenges in this field of ZABs are also discussed.
In this review, the authors provide a comprehensive survey on recent research in Fe‐based single‐atom/dual‐atom electrocatalysts applied as air electrodes of zinc–air batteries, and deeply discuss the relationship between active‐site coordination and battery performance, potentially offering guidelines for future related investigations.
Aqueous zinc‐ion batteries (ZIBs) have triggered a great deal of scientific research and become a promising alternative for large‐scale energy storage applications, owing to the unique merits of high ...volumetric energy density, abundance of zinc resources, eco‐friendliness, and safety. The pace of progress of ZIB development, however, is hindered by their poor reversibility and sluggish kinetics, derived from the dissolution of active materials in aqueous electrolytes and the strong electrostatic interactions between Zn2+ and the cathode lattice. Herein, a vanadium oxide (V2O5‐x)/polyaniline (PANI‐V) superlattice structure is demonstrated as a model of superlattice structural engineering to overcome these weaknesses. In this superlattice, the PANI layer not only plays the role of a spacer to expand the V2O5‐x interlayer spacing but also serves as a conductive capacity contributor. Moreover, the PANI layer servers as structural stabilizer to restrain the dissolution of V2O5‐x active materials in aqueous electrolytes. In addition, it introduces an interface effect to modulate the charge distribution of the V2O5‐x monolayer, promoting Zn‐ion diffusion into the structure. Correspondingly, weakening the electrostatic interactions and supressing the active materials dissolution synergistically boosts the electrochemical performance for Zn‐ion storage. This work paves the way for the development/improvement of cathodes for aqueous zinc‐ion batteries.
A vanadium oxide (V2O5‐x)/polyaniline superlattice is demonstrated as a model to improve Zn2+ diffusion kinetics and suppress cathode dissolution. It benefits from the unique advantages of 2D superlattice structure including enlarged layer spacing, interface modulation inducing the charge redistribution and structure stabilization. This structural engineering strategy paves the way for the development of new cathodes for zinc‐ion batteries.
This paper presents an overview of the various types of lithium salts used to conduct Li+ ions in electrolyte solutions for lithium rechargeable batteries. More emphasis is paid towards lithium salts ...and their ionic conductivity in conventional solutions, solid–electrolyte interface (SEI) formation towards carbonaceous anodes and the effect of anions on the aluminium current collector. The physicochemical and functional parameters relevant to electrochemical properties, that is, electrochemical stabilities, are also presented. The new types of lithium salts, such as the bis(oxalato)borate (LiBOB), oxalyldifluoroborate (LiODFB) and fluoroalkylphosphate (LiFAP), are described in detail with their appropriate synthesis procedures, possible decomposition mechanism for SEI formation and prospect of using them in future generation lithium‐ion batteries. Finally, the state‐of‐the‐art of the system is given and some interesting strategies for the future developments are illustrated.
All charged up: An overview of the various types of lithium salts used to conduct Li+ ions in electrolyte solutions for rechargeable lithium batteries is presented. Emphasis is paid towards lithium salts and their ionic conductivity in conventional solutions, solid electrolyte interface formation towards carbonaceous anodes and the effect of the anion on the aluminium current collector.
Hard carbon (HC) is recognized as a promising anode material with outstanding electrochemical performance for alkali metal‐ion batteries including lithium‐ion batteries (LIBs), as well as their ...analogs sodium‐ion batteries (SIBs) and potassium‐ion batteries (PIBs). Herein, a comprehensive review of the recent research is presented to interpret the challenges and opportunities for the applications of HC anodes. The ion storage mechanisms, materials design, and electrolyte optimizations for alkali metal‐ion batteries are illustrated in‐depth. HC is particularly promising as an anode material for SIBs. The solid‐electrolyte interphase, initial Coulombic efficiency, safety concerns, and all‐climate performances, which are vital for practical applications, are comprehensively discussed. Furthermore, commercial prototypes of SIBs based on HC anodes are extensively elaborated. The remaining challenges and research perspectives are provided, aiming to shed light on future research and early commercialization of HC‐based SIBs.
Hard carbon (HC) is recognized as a promising anode material for alkali‐metal ion batteries, especially for sodium‐ion batteries (SIBs) which are cost effective for grid‐scale energy storage. This review aims for a comprehensive understanding of alkali‐metal ion storage mechanisms in HC, and also rational approaches to enhance the performance of HC anodes for practical SIBs.
The low-cost room-temperature sodium-sulfur battery system is arousing extensive interest owing to its promise for large-scale applications. Although significant efforts have been made, resolving low ...sulfur reaction activity and severe polysulfide dissolution remains challenging. Here, a sulfur host comprised of atomic cobalt-decorated hollow carbon nanospheres is synthesized to enhance sulfur reactivity and to electrocatalytically reduce polysulfide into the final product, sodium sulfide. The constructed sulfur cathode delivers an initial reversible capacity of 1081 mA h g
with 64.7% sulfur utilization rate; significantly, the cell retained a high reversible capacity of 508 mA h g
at 100 mA g
after 600 cycles. An excellent rate capability is achieved with an average capacity of 220.3 mA h g
at the high current density of 5 A g
. Moreover, the electrocatalytic effects of atomic cobalt are clearly evidenced by operando Raman spectroscopy, synchrotron X-ray diffraction, and density functional theory.
Sodium metal is an ideal anode material for metal rechargeable batteries, owing to its high theoretical capacity (1166 mAh g−1), low cost, and earth‐abundance. However, the dendritic growth upon Na ...plating, stemming from unstable solid electrolyte interphase (SEI) film, is a major and most notable problem. Here, a sodium benzenedithiolate (PhS2Na2)‐rich protection layer is synthesized in situ on sodium by a facile method that effectively prevents dendrite growth in the carbonate electrolyte, leading to stabilized sodium metal electrodeposition for 400 cycles (800 h) of repeated plating/stripping at a current density of 1 mA cm−2. The organic salt, PhS2Na2, is found to be a critical component in the protection layer. This finding opens up a new and promising avenue, based on organic sodium slats, to stabilize sodium metals with a protection layer.
A sodium benzenedithiolate (PhS2Na2)‐rich protection layer synthesized in situ on sodium by a facile method effectively prevents dendrite growth in carbonate electrolyte, leading to stabilized sodium metal electrodeposition for 400 cycles (800 h) of repeated plating/stripping at a current density of 1 mA cm−2.
PDF
