用于锂离子电池的石墨烯及其复合负极材料的研究进展

石墨烯复合材料因具有高比表面积、高比容量、优异的导电性、显著的化学稳定性,在锂离子电池领域具有巨大的应用前景。在负极复合材料中,石墨烯不仅可以形成导电网络提升复合材料的导电性能,而且还可以缓冲材料在充放电过程中的体积效应,提高了材料的倍率性能和循环寿命,为设计大容量高稳定性的锂离子电池提供了理论保证。因此制备不同组成和结构的石墨烯复合材料是一个非常有价值的课题。对近年来国内外运用不同方法制备不同组成和结构的石墨烯复合材料的研究结果做了综合评述和展望。     

石墨烯及其复合材料作为锂离子电池负极材料的研究进展

石墨烯作为一种锂离子电池负极材料表现出优异的电化学性能。本文介绍了石墨烯负极材料、金属/石墨烯复合材料、金属氧化物/石墨烯复合材料和其他石墨烯复合材料的研究现状,阐述了石墨烯作为负极材料的优越性,展望了石墨烯及其复合复合材料在锂离子电池负极材料中的应用前景。     

石墨烯/CuO锂离子电池负极材料的研究进展

石墨烯作为一种锂离子电池负极材料表现出优异的电化学性能,但石墨烯在充放电过程中容易团聚,导致其容量衰减特别快。而金属氧化物在充放电过程中体积膨胀大,因此其容量衰减也非常快;另外,金属氧化物的电导率低,导致其倍率性能差。将金属氧化物与石墨烯复合,两者性能互补,石墨烯可提高复合材料的电导率,缓解金属氧化物在充放电过程中的体积效应;金属氧化物可提高复合材料的储锂容量,并能阻止石墨烯在充放电过程中团聚。本文介绍了石墨烯/CuO锂离子电池负极材料的制备方法,分析了石墨烯与氧化铜及其复合材料的储锂机制,展望了石墨烯/CuO锂离子电池负极材料的应用前景,并指出了当前研究中存在的问题。     

石墨烯/金属氧化物锂离子电池负极材料的研究进展

石墨烯作为锂离子电池负极材料时,比克容量是石墨的两倍,但是纯石墨烯因其在充放电过程中团聚,导电循环性能差。为了延长石墨烯的循环寿命,一种有效的方法是在石墨烯中加入过渡金属氧化物(CoOx,CuOx,NiOx,FeOx和MnOx等)。这些过渡金属氧化物比克容量高(700~1000mAh/g),但是在充放电过程中发生体积膨胀,导致其循环性能差。过渡金属氧化物与石墨烯复合后,能够弥补彼此的缺点,具有优异的电化学性能。综述了石墨烯/过渡金属氧化物复合物在锂离子电池负极材料上的应用,并研究了石墨烯加入后对复合材料的性能提升的原因。     

石墨烯及复合材料作锂离子电池电极的进展

石墨烯是一种单原子层厚度的石墨材料,具有独特的二维结构和优异的电学、力学及化学稳定性。此外,石墨烯还具有特殊sp^2结构,易于与其它材料复合。利用石墨烯获得具有特殊形貌和微观结构的电极材料,能有效改善材料的各项电化学性能,作为锂离子电池的电极材料具有潜在的应用前景。总结了近些年对石墨烯及复合材料作为锂离子电池电极材料的研究,重点阐述了材料的制备、电学性质及基本原理,为其作为锂离子电极材料的应用提供相应的理论依据。     

石墨烯基复合物作为锂离子电池正极材料的研究进展

石墨烯因其高导电、导热效应等而备受储能领域的关注,其复合材料用作锂离子电池负极材料时显著提升了锂离子电池的电化学性能。综述了石墨烯基复合材料作为锂离子电池正极材料的合成方法及电化学性能的研究。     

类石墨烯二硫化钼在锂离子电池负极材料中的研究进展

综述了近年来国内外应用于锂离子电池负极材料的类石墨烯MoS2基材料的研究进展。简要介绍了其晶体结构、制备方法、嵌锂反应机理,并详细介绍了2H-MoS2基材料在锂离子电池负极领域的研究进展,包括水热法、硬模板法和溶剂热法制备特殊形貌的2H-MoS2,以及无定形碳、介孔碳分子筛、碳纳米管、石墨烯/2H-MoS2复合材料及高分子聚合物/C/2H-MoS2复合材料的最新研究现状。     

石墨烯及其复合材料在锂离子电池负极材料中的应用

石墨烯作为一种仅有单原子层厚度的新型碳材料,具有独特的结构和优异的电学、热学、力学等性能.石墨烯的产业化应用一直是国际上的研究热点.由于其高电导率、超大的比表面积、高化学稳定性等优异的物理和化学特性,石墨烯作为锂离子电池电极材料有着巨大的应用前景.综述了近5年来石墨烯及其复合材料在锂离子电池负极材料中应用的最新研究成果和进展,并对今后的研究工作进行了展望.     

新型锂离子电池正极材料的研究现状及其发展前景

近年来锂离子电池的发展非常引人注目，它除了在传统便携式电器市场的应用得到进一步稳定发展，并占据重要的地位外，在电动汽车动力电源及其储能电池方面的应用前景也特别引人关注。锂离子电池目前仍朝着高能量密度、高功率密度及大型化方向发展，例如，商用锂离子电池的能量密度虽已实现200Wh／kg的指标，但市场的需求仍然需要锂离子电池的能量密度进一步提高，     

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.     

Nanostructured organic electrode materials grown on graphene with covalent-bond interaction for high-rate and ultra-long-life lithium-ion batteries

Nanostructured organic tetralithium salts of 2,5-dihydroxyterephthalic acid (Li₄C₈H₂O₆) supported on graphene were prepared via a facile recrystallization method. The optimized composite with 75 wt.% Li₄C₈H₂O₆ was evaluated as an anode with redox couples of Li₄C₈H₂O₆/Li₆C₈H₂O₆ and as a cathode with redox couples of Li₄C₈H₂O₆/Li₂C₈H₂O₆ for Li-ion batteries, exhibiting a high-rate capability (10 C) and long cycling life (1,000 cycles). Moreover, in an all-organic symmetric Li-ion battery, this dual-function electrode retained capacities of 191 and 121 mA·h·g^–1 after 100 and 500 cycles, respectively. Density functional theory calculations indicated the presence of covalent bonds between Li₄C₈H₂O₆ and graphene, which affected both the morphology and electronic structure of the composite. The special nanostructures, high electronic conductivity of graphene, and covalent-bond interaction between Li₄C₈H₂O₆ and graphene contributed to the superior electrochemical properties. Our results indicate that the combination of organic salt molecules with graphene is useful for obtaining high-performance organic batteries.

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Graphene: A promising candidate for charge regulation in high-performance lithium-ion batteries

The development of rechargeable lithium-ion batteries (LIBs) is being driven by the ever-increasing demand for high energy density and excellent rate performance. Charge transfer kinetics and polarization theory, considered as basic principles for charge regulation in the LIBs, indicate that the rapid transfer of both electrons and ions is vital to the electrochemical reaction process. Graphene, a promising candidate for charge regulation in high-performance LIBs, has received extensive investigations due to its excellent carrier mobility, large specific surface area and structure tunability, etc. Recent progresses on the structural design and interfacial modification of graphene to regulate the charge transport in LIBs have been summarized. Besides, the structure-performance relationships between the structure of the graphene and its dedicated applications for LIBs have also been clarified in detail. Taking graphene as a typical example to explore the mechanism of charge regulation will outline ways to further understand and improve carbon-based nanomaterials towards the next generation of electrochemical energy storage devices.

     

Artificial interphase engineering of electrode materials to improve the overall performance of lithium-ion batteries

The overall performance of lithium-ion batteries (LIBs) is closely related to the interphase between the electrode materials and electrolytes. During LIB operation, electrolytes may decompose on the surface of electrode materials, forming a solid electrolyte interphase (SEI) layer. Ideally, the SEI layer should ensure reversible lithium-ion intercalation in the electrodes and suppress interfacial interactions. However, the chemical and mechanical stabilities of the SEI layer are not usually able to meet these requirements. Alternatively, tremendous efforts have been devoted to engineering the surface of electrode materials with an artificial interphase, which shows great promise in improving the electrochemical performance. Herein, we present a comprehensive summary of the state-of-the-art knowledge on this topic. The effects of the artificial interphase on the electrochemical performance of the electrode materials are discussed in detail. In particular, we highlight the importance of three functions of artificial interphases, including inhibiting electrolyte decomposition, protecting the electrodes from corrosion, and accommodating electrode volume changes.

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锂离子电池高镍三元材料的研究进展

用于锂离子电池的高镍三元材料由于成本低、能量密度高、可逆容量高、环境友好等优点,是现在以及未来车用动力电池首选正极材料。本文在综述了高镍三元材料的晶体结构特性和电化学特性的基础上,介绍了国内外主要制备方法、掺杂以及包覆等改性措施,重点讨论了不同种类包覆材料对高镍三元倍率性能、循环性能和高温稳定性能的影响。最后,针对高镍三元电解液、安全性、压实密度及循环寿命等问题进行分析与展望。     

Lithium storage in amorphous TiNi hydride: Electrode for rechargeable lithium-ion batteries

In this study, amorphous TiNi phase was successfully prepared using mechanically milling for a very short time of 8 h. HRTEM confirms the formation of amorphous phase with the presence of nanocrystalline Fe particles. After hydrogenation (30 bars of H₂ for a duration of 2 h), the electrochemical reaction shows that TiNi hydride/Li cell discharges at a current of one Li for 10 h between 3 V and 0.005 V. The discharge of TiNiH electrode around x = 1 Li corresponds to a capacity of 251 mAh g⁻¹ and a hydride composition of TiNiH_1.0 at an average voltage of 0.4 V. Ex-situ X-ray diffraction pattern collected at the end of the discharge shows a mixture of amorphous TiNi compound and LiH. A general mechanism for the electrochemical reaction is then proposed: α-TiNiH + Li⁺ + e⁻ → α-TiNi + LiH. The results from DFT calculations yield an average cell voltage of 0.396 V, which is in good agreement with the experimental pseudo-plateau occurring at 0.4 V.     

Hydrothermal synthesis and electrochemical properties of alpha-manganese sulfide submicrocrystals as an attractive electrode material for lithium-ion batteries

A convenient hydrothermal synthetic route has been successfully developed to prepare stable rock-salt-type structure α-MnS submicrocrystals under mild conditions. In this synthetic system, hydrated manganese chloride (MnCl₄·4H₂O) was used to supply a highly reactive manganese source, thiourea ((NH₂)₂CS) was used to supply the sulfide source and aqueous hydrazine (N₂H₄·H₂O) was used as both alkaline and reducing agent. The results revealed that the electrochemical performance of the α-MnS submicrocrystals may be associated with the degree of crystallinity and particle size of samples. The initial lithiation capacity of the α-MnS submicrocrystals obtained at 120 °C is 1327 mAh g⁻¹ at 0.7 V versus Li/Li⁺, which exhibited α-MnS submicrocrystals is extremely promising anode material for lithium-ion batteries and has great potential applications in the future.     

Preparation and electrochemical properties of nano-sized SnF2 as negative electrode for lithium-ion batteries

Nanocrystalline SnF₂ was prepared via recrystallization of commercially available tin (II) fluoride. The electrochemical performance of tin fluoride as anode material for Li-ion batteries was investigated. The cyclic voltammetry of the obtained material showed occurrence of SnF₂ decomposition at first and a typical reversible alloying/de-alloying process at low potentials. Furthermore, it was found that the synthesized material delivered a high reversible capacity of 1016 mAh g^− 1 and a capacity retention of 54.8% after 30 cycles when the electrode was cycled at a current of 100 mA g^− 1.