Progress and perspectives on alloying-type anode materials for advanced potassium-ion batteries

Potassium-ion batteries (PIBs) have attracted increasing interest as promising alternatives to lithium-ion batteries (LIBs) for application in large-scale electrical energy storage systems (EESSs) owing to a wide earth-abundance, potential price advantages, and low standard redox potential of potassium. Developmental materials for use in PIBs that can yield high specific capacities and durability are widely sought with emerging studies on alloying-type anode materials offering significant prospects to meet this challenge. Here, recent advances on alloying-type anodes and their composites for PIBs are reviewed in detail and in a systematic way to capture key aspects from fundamental working principles through major progress and achievements to future perspectives and challenges. Emphasis is placed on critical aspects such as the alloying mechanism and correlation of electrode design and structural engineering for performance enhancement and the crucial role of electrolyte compatibility, additives and binders. The review in appraising all the important contributions on this topic allows for a critical assessment of the research challenges and provides insights on future research directions that can accelerate the important development of PIBs as a viable battery energy storage system.     

Advances and perspectives on one-dimensional nanostructure electrode materials for potassium-ion batteries

Potassium-ion batteries (PIBs) have aroused considerable interest as a promising next-generation advanced large-scale energy storage system due to the abundant potassium resources and high safety. However, the K⁺ with large ionic radius brings restricted diffusion kinetics and severe volume expansion in electrode materials, resulting in inferior actual rate characteristics and rapid capacity fading. Designing electrode materials with one-dimensional (1D) nanostructure can effectively enhance various electrochemical properties due to the well-guided electron transfer pathways, short ionic diffusion channels and high specific surface areas. In this review, we summarize the recent research progress and achievements of 1D nanostructure electrode materials in PIBs, especially focusing on the development and application of cathode and anode materials. The nanostructure, synthetic methods, electrochemical performances and structure-performance correlation are discussed in detail. The advanced characterizations on the reaction mechanisms of 1D nanostructure electrode materials in PIBs are briefly summarized. Furthermore, the main future research directions of 1D nanostructure electrode materials are also predicted, hoping to accelerate their development into the practical PIBs market.     

Advanced polyanionic electrode materials for potassium-ion batteries: Progresses,challenges and application prospects

Although potassium-ion batteries (KIBs) are considered a very promising energy storage system, their development for actual application still has a long way to go. Advanced electrode materials, as a fundamental component of KIBs, are essential for optimizing electrochemical performance and promoting effective energy storage. Due to their unique structural benefits in terms of cycle capability, strong ionic conductivity, and tunable operating voltage, polyanionic compounds are one type of viable electrode material for manufacturing high-performance KIBs. The huge size of K⁺ ion, on the other hand, places great demands on polyanionic materials, which must be able to withstand severe structural deformation during K⁺ intercalation/delamination. To maintain steady electrochemical performance, it is critical to follow the appropriate design guidelines for electrode materials. This paper provides a summary of current advancements in polyanionic compound for KIBs, with a focus on electrode material structural design. The effects of various parameters on electrochemical performance are examined and summarized. In addition, various viable solutions are proposed to address the impending issues posed by polyanionic compounds for KIBs, with the hope of providing a clearer picture of the field's future development path.     

Recent advances in gel materials with special wettability: a review

Journal of Materials Science - The special wettable gel material solves the problem that the rigid solid surface with special wettability does not perform well in the face of flexibility...     

锂离子二次电池负极材料的研究综述

总结了在碳材料、合金材料和复合材料等3个锂离子电池负极材料研发的主导方向上的开发情况和它们各自特点,描述了目前的研究所面临难题,给出了锂离子电池负极材料研发取得重大突破的可能途径和建议.     

A review of the development of full cell lithium-ion batteries: The impact of nanostructured anode materials

Lithium-ion batteries have emerged as the best portable energy storage device for the consumer electronics market. Recent progress in the development of lithiumion batteries has been achieved by the use of selected anode materials, which have driven improvements in performance in terms of capacity, cyclic stability, and rate capability. In this regard, research focusing on the design and electrochemical performance of full cell lithium-ion batteries, utilizing newly developed anode materials, has been widely reported, and great strides in development have been made. Nanostructured anode materials have contributed largely to the development of full cell lithium-ion batteries. With this in mind, we summarize the impact of nanostructured anode materials in the performance of coin cell full lithium-ion batteries. This review also discusses the challenges and prospects of research into full cell lithium-ion batteries.

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Recent advances in solid polymer electrolytes for lithium batteries

Solid polymer electrolytes are light-weight, flexible, and non-flammable and provide a feasible solution to the safety issues facing lithium-ion batteries through the replacement of organic liquid electrolytes. Substantial research efforts have been devoted to achieving the next generation of solid-state polymer lithium batteries. Herein, we provide a review of the development of solid polymer electrolytes and provide comprehensive insights into emerging developments. In particular, we discuss the different molecular structures of the solid polymer matrices, including polyether, polyester, polyacrylonitrile, and polysiloxane, and their interfacial compatibility with lithium, as well as the factors that govern the properties of the polymer electrolytes. The discussion aims to give perspective to allow the strategic design of state-of-the-art solid polymer electrolytes, and we hope it will provide clear guidance for the exploration of high-performance lithium batteries.

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锂离子电池正极材料的研究进展

研究与开发新型的电池正极材料是锂离子电池研究中的一项重要内容．目前正极材料的研究主要集中于3种富锂的金属氧化物LiCoO2、LiNiO2和LiMn2O4。本文主要介绍了锂离子电池正极材料的合成方法,同时比较了几种不同电极材料的结构以及电化学性能,指出了其工作特点和存在问题,并对该领域的研究现状进行了简要的综述。本文还介绍了锂离子电池正极材料计算研究的进展。利用VASP软件包可计算形成能、相图、电压和材料的晶体结构参数及态密度等。     

Recent advances in thermoelectric materials

Thermoelectric materials are crucial in renewable energy conversion technologies to solve the global energy crisis. They have been proven to be suitable for high-end technological applications such as missiles and spacecraft. The thermoelectric performance of devices depends primarily on the type of materials used and their properties such as their Seebeck coefficient, electrical conductivity, thermal conductivity, and thermal stability. Classic inorganic materials have become important due to their enhanced thermoelectric responses compared with organic materials. In this review, we focus on the physical and chemical properties of various thermoelectric materials. Newly emerging materials such as carbon nanomaterials, electronically conducting polymers, and their nanocomposites are also briefly discussed. Strategies for improving the thermoelectric performance of materials are proposed, along with an insight into semiconductor physics. Approaches such as nanostructuring, nanocomposites, and doping are found to enhance thermoelectric responses by simultaneously tuning various properties within a material. A recent trend in thermoelectric research shows that high-performance thermoelectric materials such as inorganic materials and carbon nanomaterials/electronically conducting polymer nanocomposites may be suitable for power generation and energy sustainability in the near future.     

Recent developments in electrode materials for dual-ion batteries: Potential alternatives to conventional batteries

Lithium-ion batteries (LIBs), known as “rocking-chair batteries”, have shown a huge success in consumer electronics and energy vehicles. However, the soaring cost caused by the shortage of lithium and cobalt resources as well as the need for ever-higher performance and safety has promoted an urgent need to develop high-efficient battery systems. Dual-ion batteries (DIBs), based on different working mechanism that involves both cations and anions during the charging/discharging processes, are expected to be an alternative to conventional batteries due to their environmental friendliness, low cost, excellent safety, high work voltage, and high energy density. Despite these merits, DIBs also face various challenges from the limited capacity caused by intercalation-type graphite electrodes and shorter cycle life resulted from large anions intercalation and electrolyte decomposition at high voltage. To overcome those challenges, various effective strategies have been adopted and many inspiring results have been also reported. In this review, we briefly outlined the history, mechanism and configuration of DIBs and mainly summarized the recent developments of electrode materials for DIBs, covering inorganic electrode materials and organic electrode materials, along with their application in various metal-based DIBs. Especially, recent studies on organic electrode materials based on so-called DIB working mechanism are also highlighted. In addition, the existing problems and future perspectives are finally proposed. We hope this review will provide some inspiration for researchers to rationally design more efficient electrode materials for more advanced DIB systems.     

Unveiling nanoplates-assembled Bi2MoO6 microsphere as a novel anode material for high performance potassium-ion batteries

Bismuth (Bi)-based electrode has aroused tremendous interest in potassium-ion batteries (PIBs) on account of its low cost, high electronic conductivity, low charge voltage and high theoretical capacity. However, the rapid capacity fading and poor lifespan induced by the normalized volume expansion (up to ~ 406%) and serious aggregation of Bi during cycling process hinder its application. Herein, bismuth molybdate (Bi₂MoO₆) microsphere assembled by 2D nanoplate units is successfully prepared by a facile solvothermal method and demonstrated as a promising anode for PIBs. The unique microsphere structure and the self-generated potassium molybdate (K-Mo-O species) during the electrochemical reactions can effectively suppress mechanical fracture of Bi-based anode originated from the volume variation during charge/discharge of the battery. As a result, the Bi₂MoO₆ microsphere without hybridizing with any other conductive carbon matrix shows superior electrochemical performance, which delivers a high reversible capacity of 121.7 mAh·g⁻¹ at 100 mA·g⁻¹ over 600 cycles. In addition, the assembled perylenetetracarboxylic dianhydride (PTCDA)//Bi₂MoO₆ full-cell coupled with PTCDA cathode demonstrates the potential application of Bi₂MoO₆ microsphere. Most importantly, the phase evolution of Bi₂MoO₆ microsphere during potassiation/depotassiation process is successfully deciphered by ex situ X-ray diffraction (XRD), X-ray photoemission spectroscopy (XPS), and transmission electron microscopy (TEM) technologies, which reveals a combination mechanism of conversion reaction and alloying/dealloying reaction for Bi₂MoO₆ anode. Our findings not only open a new way to enhance the performance of Bi-based anode in PIBs, but also provide useful implications to other alloy-type anodes for secondary alkali-metal ion batteries.

     

锡锑合金/石墨复合材料作为锂离子电池负极的研究

通过球磨的方法制备了锡锑合金/石墨复合材料,应用XRD、SEM和电化学方法对锡锑合金/石墨复合材料的微观结构和电化学性能做了研究.复合材料的首次可逆容量达到416 mAh/g,锡锑合金/石墨复合材料的循环稳定性相比于锡锑合金有了很明显的改善.对锡锑合金含量与复合材料吸放锂性能的研究表明,含锡锑合金50%的锡锑合金/石墨复合材料循环稳定性最好,到第20个循环时,容量保持率为88%(锡锑合金为81%),是有希望的锂离子电池负极材料.     

锰氧化物/石墨烯复合材料作为锂离子电池负极的研究

以天然石墨为原料,采用改进的Hummers法合成含Mn的氧化石墨;400℃条件下氢气还原制备了锰氧化物/石墨烯复合材料。利用XRD、SEM和TEM对所制备的复合材料进行了表征。结果表明锰氧化物(MnOx)颗粒均匀地分布在石墨烯片层表面。将复合材料作为锂离子电池负极进行研究,在50mA/g电流密度下,首次库伦效率为70.4%,可逆容量达876mAh/g,并且具有良好的循环性能,在30次循环后仍保持在700mAh/g以上。     

Pyrolitic carbon from biomass precursors as anode materials for lithium batteries

Disordered carbonaceous materials were synthesized by the pyrolysis of banana fibers treated with pore-forming substances such as ZnCl₂ and KOH. X-ray diffraction studies indicated a carbon structure with a large number of disorganized single layer carbon sheets. Addition of porogenic agent led to remarkable changes in the structure and morphology of the carbonaceous products. The product obtained with ZnCl₂ treatment gave first-cycle lithium insertion and de-insertion capacities of 3325 and 400 mAh g⁻¹, respectively. Lower capacities only could be realized in the subsequent cycles, although the coulombic efficiency increased upon cycling, which in the 10th cycle was 95%.     

Nickel-cobalt oxides/carbon nanoflakes as anode materials for lithium-ion batteries

Novel nickel-cobalt oxides/carbon nanoflakes with Ni/Co molar ratio = 1:1 and 1:2 have been synthesized by a convenient hydrothermal method followed by a simple calcination process. X-ray diffraction results showed that the composites were composed of NiO, Co₃O₄, and carbon. Scanning electron microscope measurements demonstrated that the composites were flakes less than 100 nm in thickness, and the corresponding energy dispersive spectroscopy mapping showed that the carbon was distributed homogeneously in the composites. The electrochemical results showed that the composite electrodes exhibited low initial coulombic efficiency and excellent charge-discharge cycling stability. Additionally, the effect of different Ni/Co molar ratios on the electrochemical properties of the composites was investigated, and better performance was obtained for the sample with a Ni/Co molar ratio of 1:2.     

Hydrothermal synthesis of SnO nanoflakes as anode materials for lithium-ion batteries

SnO nanoflakes were successfully prepared by a simple hydrothermal process, with the use of hydrazine hydrate as the mineralizer and polyethylene glycol (PEG) or citric acid as an additive. Hydrazine hydrate serves as both a mineralizer and a protective agent against the oxidation of the SnO products at the hydrothermal stage. X-ray diffraction, field-emission scanning electron microscopy (FESEM), and transmission electron microscopy were employed to characterize the products. FESEM images reveal that the thickness of the SnO nanoflakes prepared by the hydrothermal process with the use of PEG as an additive is around 15 nm. The first reversible specific capacity of the SnO nanoflakes reaches 856 mA h/g, which is near the theoretical value (876 mA h/g). Hydrazine hydrate, the hydrothermal temperature, and the surfactant/complexing agent are three key factors for the hydrothermal synthesis of the SnO nanoflakes by the process presented here. The text was submitted by the authors in English.