at an average storage voltage of 3.2 V with long cycle life. When coupled with hard carbon anode, a prototype rechargeable sodium-ion battery offers an energy density of 210 Wh kg −1 , a round-trip energy effi ciency of 90%, high rate capability, and excellent cycling stability. These desired performances make this system to be closer to the level of practical applications. The Na 0.9 [Cu 0.22 Fe 0.30 Mn 0.48 ]O 2 (Na 0.9 [Cu II 0.22 Fe III 0.30 Mn III 0.16 Mn IV 0.32 ]O 2 ) material was synthesized by a simple solid-state reaction at 850 °C in air atmosphere using precursors of Na 2 CO 3 , CuO, Fe 2 O 3 , and Mn 2 O 3 . The crystal structure of the as-synthesized material was determined by X-ray diffraction (XRD) as shown in Figure 1 a together with its refi nement results by the Rietveld method (see Table S1, Supporting Information). It can be seen that all the Bragg diffraction peaks are in excellent agreement with the JC DS No. 01-0821495 (O3-type α-NaFeO 2 ) and can be indexed to a hexagonal layered structure with a space group of 3 R m − , indicative of a typical O3-type layered structure (note that the letter “O” refers to the Na coordination environment of octahedral site whereas the number “3” refers to the number of MO 2 slab according to Delmas’ notation. [ 13 ] A schematic illustration of the O3-type structure is also shown in Figure 1 b. The structure refi nement gives the lattice parameters a = 2.9587(7) A, c = 16.3742(6) A. The lattice parameter of c -axis is slightly larger than that of other O3-type materials [ 5f–h , 6b , 8a ] because the Na content is less than 1. The inductively coupled plasma (ICP) result confi rms the composition of Na 0.89 [Cu 0.22 Fe 0.30 Mn 0.48 ]O 2 (see Table S2, Supporting Information). The morphology of the resulting sample is shown in Figure 1 c. The distribution of the particle size is in the range of 10–30 μm with about 3 μm sized primary particle agglomerations together (Figure 1 d). Most importantly, unlike other O3-type materials, [ 4–9,12 ] this material is very stable against water. In order to confi rm this, we intentionally design an accelerated aging experiment as described in the Experimental Section which was verifi ed by LiMO 2 as shown in Figure S1 (Supporting Information). We placed the as-synthesized material in deionized water for 3 d and then dried the material at 100 °C for overnight. The obtained material was checked by XRD again. It can be seen that the XRD pattern is nearly identical to that of the as-synthesized material, which is very different from other O3-type materials as shown in Figure S2 (Supporting Information). These results suggest that the O3-Na 0.9 [Cu 0.22 Fe 0.30 Mn 0.48 ]O 2 is very stable against water. Furthermore, after the material was stored in air for one month Large-scale electrical energy storage systems are one of the core technologies in renewable energies and smart grid, among which sodium-ion batteries show great promise due to the abundant sodium resources. Layered metal oxides (of general formula: A x MO 2 , where A = Li, Na; M = Co, Ni, Mn, Cr, Fe, etc.) with alternating alkali metal layer and transition metal layer have long been of particular interest since the early 1980s as an important class of cathode materials for rechargeable batteries due to their easy synthesis and high energy density. [ 1 ] One of the most successful examples is LiCoO 2 , [ 1a ] which is commonly used as a cathode in lithium-ion batteries with the highest volumetric energy density for portable electronic devices. Its metal substituted materials (LiCo 1− x − y − z Ni x Mn y Al z O 2 ) are being used in power batteries for electric vehicles. In the case of sodiumion batteries operated at room temperature which are proposed for large-scale electrical energy storage owing to the naturally abundant sodium resources in recent years. [ 2,3 ] Na x CoO 2 that can electrochemically and reversibly intercalate Na is the fi rst example, [ 1b ] then a large number of layered metal oxides have been extensively exploited. [ 4–12 ] However, the practical applications have been hindered by two major challenges. First, unlike LiMO 2 , almost all the Na x MO 2 are not stable against moisture (either they can be oxidized by water or water/carbon dioxide molecules can be intercalated into alkali metal layer). [ 4–9,11,12 ]

/pdf/prototype-sodium-ion-batteries-using-air-stable-and-co-ni-5fwg7s03of.pdf

Prototype Sodium-Ion Batteries Using Air-Stable and Co/Ni-Free O3-Layered Metal Oxide Cathode

O3-Type layered oxides are widely studied as cathodes for sodium-ion batteries (SIBs) due to their high theoretical capacities. However, their rate capability and durability are limited by tortuous Na+ diffusion channels and complicated phase evolution during Na+ extraction/insertion. Here we report our findings in unravelling the mechanism for dramatically enhancing the stability and rate capability of O3-NaNi0.5Mn0.5-xSbxO2 (NaNMS) by substitutional Sb doping, which can alter the coordination environment and chemical bonds of the transition metal (TM) ions in the structure, resulting in a more stable structure with wider Na+ transport channels. Furthermore, NaNMS nanoparticles are obtained by surface energy regulation during grain growth. The synergistic effect of Sb doping and nanostructuring greatly reduces the ionic migration energy barrier while increasing the reversibility of the structural evolution during repeated Na+ extraction/insertion. An optimized NaNMS-1 electrode delivers a reversible capacity of 212.3 mAh g-1 at 0.2 C and 74.5 mAh g-1 at 50 C with minimal capacity loss after 100 cycles at a low temperature of -20 °C. Such electrochemical performance is superior to most of the reported layered oxide cathodes used in rechargeable SIBs.

A High-Rate, Durable Cathode for Sodium-Ion Batteries: Sb-Doped O3-Type Ni/Mn-Based Layered Oxides.

Abstract In recent decades, sodium‐ion batteries (SIBs) have received increasing attention because they offer cost and safety advantages and avoid the challenges related to limited lithium/cobalt/nickel resources and environmental pollution. Because the sodium storage performance and production cost of SIBs are dominated by the cathode performance, developing cathode materials with large‐scale production capacity is the key to achieving commercial applications of SIBs. Therefore, developing host materials with high energy density, long cycling life, low production cost, and high chemical/environmental stability is crucial for implementing advanced SIBs. Among the developed cathode materials for SIBs, O3‐type sodiated transition‐metal oxides have attracted extensive attention owing to their simple synthesis methods, high theoretical specific capacity, and sufficient Na content. However, the relatively large Na‐ion radius leads to sluggish diffusion kinetics and inevitable complex phase transitions during the deintercalation/intercalation process, resulting in poor rate capability and cycling stability. Therefore, this review comprehensively summarizes the research progress and modification strategies for O3‐type cathodes, including the component design, surface modification, and optimization of synthesis methods. This work aims to guide the development of commercial layered oxides and provide technical support for the next generation of energy‐storage systems. 

Practical Cathodes for Sodium‐Ion Batteries: Who Will Take The Crown?

Stable Electrochemical Properties of Magnesium-Doped Co-Free Layered P2-Type Na0.67Ni0.33Mn0.67O2 Cathode Material for Sodium Ion Batteries

Sodium-ion batteries have received significant interest as a cheaper alternative to lithium-ion batteries and could be more viable for use in large scale energy storage systems. However, similarly to lithium-ion batteries, their performance remains limited by the positive electrode materials. Layered transition metal oxides, with chemical formula NaxMO2, have been extensively investigated and appear to show the most promise. However, the inability to reversibly extract large amounts of sodium ions from these layered structures, by charging to high voltages, has limited the useful capacity and cycle life of these materials. To address this, numerous studies have attempted to resolve the structural and chemical changes that take place in positive electrode materials upon cycling. This is particularly important at and near the charged state, which is where the materials' structures are highly sodium deficient. Following a brief introduction into the status of sodium-ion battery positive electrodes, this work focuses on the development of knowledge and understanding into the structure of layered oxides at the charged state by highlighting cutting edge characterisation techniques that have been utilised. Finally, a perspective on future development is provided to direct further structural characterisation research which will enable the rational design of new and improved energy storage materials.

/pdf/probing-the-charged-state-of-layered-positive-electrodes-in-16suykpk28.pdf

Probing the charged state of layered positive electrodes in sodium-ion batteries: reaction pathways, stability and opportunities

Core–Shell Structure and X‐Doped (X = Li, Zr) Comodified O3‐NaNi0.5Mn0.5O2: Excellent Electrochemical Performance as Cathode Materials of Sodium‐Ion Batteries

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Min Wang

Author Tools

Chat about Author

Papers

Core–Shell Structure and X‐Doped (X = Li, Zr) Comodified O3‐NaNi0.5Mn0.5O2: Excellent Electrochemical Performance as Cathode Materials of Sodium‐Ion Batteries