稀土化合物应用于高能锂硫电池的研究进展

锂硫电池是极具开发潜力和应用前景的新一代高比能金属锂二次电池.拥有独特4f轨道的稀土元素及其化合物具有特殊的光、电、磁与催化等性质,研究发现将稀土化合物引入锂硫电池体系能够有效解决制约锂硫电池发展的穿梭效应和锂枝晶问题并显著提升电池性能.本文全面综述了稀土化合物应用于锂硫电池正极、隔膜和电解质的最新研究进展和动态及其解...     

锂离子电池负极材料Li_4Ti_5O_(12)的制备及电化学性能

采用嵌段聚合物型表面活性剂P123作为结构导向剂,利用溶胶-凝胶方法制备出纳米TiO2作为合成Li4Ti5O12锂离子电池负极材料的原料之一.然后采用湿法球磨辅助的固相反应合成方法,以丙酮作为球磨介质,制备出Li4Ti5O12锂离子电池负极材科,并对所制备的Li4Ti5O12电极材料进行扫描电镜SEM、透射电镜TEM、粉末X射线衍射(XRD)、循环伏安(CV)以及循环性能测试.电化学性能测试表明所制各出的锂离子电池负极材料Li4Ti5O12具有较高的放电比容量和优异的循环性能.在电流密度为16 mA/g时首次放电比容量为155 mAh/g,首次库仑效率为98.3%.300次循环结束时放电比容量仍可达150.8 mAh/g,约为首次放电比容量的97.3%,300次循环容量仅衰减了2.7%.     

可充锂电池的锂金属电极枝晶的抑制

全固态可充锂二次电池的循环性能受到负极锂金属表面形成的枝晶影响。研究了一种能够有效抑制金属锂电极表面枝晶形成的方法。利用等离子体处理隔膜表面,在表面接枝上磺酸基,可以有效地稳定金属锂/隔膜界面,抑制枝晶形成,有效提高锂金属电极的循环稳定性。基于局域微电池模型提出了这种枝晶形成被有效抑制的机理。     

锂离子电池的工作原理与关键材料

锂离子电池具有能量密度高、自放电小和循环寿命长等优点,被广泛用于便携式电子设备和电动汽车等方面,不断推动着社会朝着智能化和清洁化方向发展.简要阐述了锂离子电池的发展历程和工作原理,从材料结构和储锂机制方面对正极材料和负极材料进行分类并综述其性能特点与研究现状,介绍了液态电解液中锂盐、溶剂、添加剂以及固态电解质在锂离子电...     

Hierarchical CuO hollow microspheres: Controlled synthesis for enhanced lithium storage performance

In this work, hierarchical CuO hollow microspheres were hydrothermally prepared without use of any surfactants or templates. By controlling the formation reaction conditions and monitoring the relevant reaction processes using time-dependent experiments, it is demonstrated that hierarchical CuO microspheres with hollow interiors were formed through self-wrapping of a single layer of radically oriented CuO nanorods, and that hierarchical spheres could be tuned to show different morphologies and microstructures. As a consequence, the formation mechanism was proposed to proceed via a combined process of self-assembly and Ostwald's ripening. Further, these hollow microspheres were initiated as the anode material in lithium ion batteries, which showed excellent cycle performance and enhanced lithium storage capacity, most likely because of the synergetic effect of small diffusion lengths in building blocks of nanorods and proper void space that buffers the volume expansion. The strategy reported in this work is reproducible, which may help to significantly improve the electrochemical performance of transition metal oxide-based anode materials via designing the hollow structures necessary for developing lithium ion batteries and the relevant technologies.     

Recent developments on anode materials for magnesium-ion batteries:a review

In recent years,there has been significant growth in the demand for secondary batteries,and researchers are increasingly taking an interest in the development of nextgeneration battery systems.Magnesium-ion batteries(MIBs) have been recognized as the optimal alternative to lithium-ion batteries(LIBs) due to their low cost,superior safety,and environment-friendliness.However,research and development on rechargeable MIBs are still underway as some serious problems need to be resolved.One of the most serious obstacles is the generation of an irreversible passivation layer on the surface of the Mg anode during cycling.In addition to exploring new electrolytes for MIBs,alternative anode materials for MIBs might be an effective solution to this issue.In this review,the composition and working principle of MIBs have been discussed.In addition,recent advances in the area of anode materials(metals and their alloys,metal oxides,and two-dimensional materials) available for MIBs and the corresponding Mg-storage mechanisms have also been summarized.Further,feasible strategies,including structural design,dimension reduction,and introduction of the second phase,have been employed to design high-performance MIB anodes.     

Electrode materials for rechargeable lithium batteries

Miniaturization in electronics and rapid advances in portable devices demand lightweight, compact, high-energy density batteries. Lithium batteries offer several advantages such as higher cell voltage, higher energy density, and longer shelf life as compared to other rechargeable systems. Although the rocking-chair concept of utilizing insertion compounds as both cathode and anode hosts has made the rechargeable lithium batteries a commercial reality, cost and environmental considerations require the development of inexpensive electrode hosts such as manganese oxides for consumer applications. Innovative synthesis and processing procedures (including low-temperature, solution-based synthesis approaches to obtain amorphous and nanocrystalline oxide electrode hosts) play a key role in developing new as well as better-performing known electrode materials.     

Improving Li Plating Behaviors Through Cu-Sn Alloy-Coated Current Collector for Dendrite-Free Lithium Metal Anodes

Alloy anode with good reversibility of lithium plating/stripping and long cycling stability is considered as promising anode materials.Here,Cu-Sn alloy is used as the substrate for Li deposition to induce the most densely packed arrangement of Li atoms,thus presenting high lithiophilicity and improving Li plating behaviors.The LiFePO_4-based full cell with the asprepared dendrite-free Li metal anode retained at 85 mAh g~(-1) with a high coulombic efficiency of 99.5% after 300 cycles,presenting a capacity retention of 79.4%.This strategy provides a new perspective to structure dendrite-free Li anode for the next-generation high-energy density batteries.     

锂离子电池及相关材料进展

新能源技术对人类社会未来可持续发展至关重要,锂离子电池可望大规模应用于电动汽车和太阳能、风能等清洁电能的储存。电动汽车电池还面临重量、体积、寿命、安全、成本和系统可靠性等诸方面的挑战。评述了钴酸锂、锰酸锂、三元材料和磷酸铁锂等正极材料;石墨、钛酸锂等负极材料;电解质材料和隔膜材料等的研究和应用,重点介绍了正极材料的掺杂和表面修饰改性技术。并对电池技术的进步和新一代锂离子电池应用于电动车辆和智能电网的前景进行了展望。     

Protecting lithium metal anode in all-solid-state batteries with a composite electrolyte

The volume of the metallic lithium anode in all-solid-state Li metal batteries increases significantly due to the lithium dendrite formation during the battery ...     

Electrolytic alloy-type anodes for metal-ion batteries

Alloy-type metals/alloys hold the promise of increasing the energy density of metal-ion batteries(MIBs)because of their theoretical high gravimetrical capacities.Semimetals and semimetal-analogs are typical alloy-type anodes.Currently,the large-scale extraction of semimetals(Si,Ge) and semimetal-analogs(Sb,Bi,Sn) by traditional metallurgical routes highly relies on using reducing agents(e.g.,carbon,hydrogen,reactive metals),which consumes a large number of fossil fuels and produces greenhouse gas emissions.In addition,the common metallurgical methods for extracting semimetals involve relatively high operating temperatures and therefore produce bulk metal ingots solidified from the liquid metals.However,the commonly used electrode materials in batteries are fine powders.Thus,directly producing semimetal powders would be more energy efficient.In addition,semimetals are good candidates to host alkali/alkaline-earth ions through the alloying process because the electronegativity of semimetals is high.Therefore,preparing semimetal powders via an environment-sound manner is of great interest to provide sustainable anode materials for MIBs while reducing the ecological footprint.Low-cost and high-output capacity anode powder materials,as well as straightforward and environmental-benign synthetic methods,play key roles in enabling the energy conversion and storage technologies for real applications of MIBs.Electrochemical technologies offer new strategies to extract semimetals using electrons as the reducing agent that comes from renewable energies.Besides,the morphologies and structures of the electrolytic products can be rationally tailored by tuning the electrode potentials,electrolytes,and operating temperatures.In this regard,using the one-step green electrochemical method to prepare high-capacity and cheaper alloy-type metalloids for MIB anodes can fulfill the requirements for developing MIBs.This review critically overviews recent developments and advances in the electrochemical extraction of semimetals(Si,Ge) and semimetal-analogs(Sb,Bi,Sn) for MIBs,including basic electrochemical principles,thermodynamic analysis,manufacture strategies and applications in lithium-ion batteries(LIBs),sodium-ion batteries(SIBs),potassium-ion batteries(PIBs),magnesium-ion batteries(Mg-ion batteries),and liquid metal batteries(LMBs).It also presents challenges and prospects of employing electrochemical approaches for preparing alloy-type anode materials directly from inexpensive ore-originated feedstocks.     

1,3-dioxolane pretreatment to improve the interfacial characteristics of a lithium anode

1,3-dioxolane （DOL） was originally used to pretreat a lithium metal electrode to improve its interfacial characteristics. Electrochemical impedance spectra （EIS） meastLrements revealed that, after the DOL pretreatment, the lithium electrode had better interfacial stability during immersion in electrolyte and as repeated charge/discharge cycles. It was proved by SEaM that the pretreated one has smoother morphology and less dendrite after repeated charge/discharge cycles. Consequentially, benefiting from the better interface characteristics of the lithium electrode, the rechargeable lithium cell with a DOL-pretreated lithium anode had the obviously enhanced discharging performance and better cyclability.     

Failure mechanism of bulk silicon anode electrodes for lithium-ion batteries

Silicon has been investigated extensively as a promising anode material for rechargeable lithium-ion batteries. Understanding the failure mechanism of silicon-based anode electrodes for lithium-ion batteries is essential to solve the problem of low coulombic efficiency and capacity fading on cycling and also to further commercialize this very new energetic material in cells. To reach this goal, the structure changes of bulk silicon particles and electrode after cycling were studied using ex-situ scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The SEM images indicated that the microstructural changes of the bulk silicon particles during cycling led to a layer rupture of the electrode and then the breakdown of the conductive network and the failure of the electrode. The result contributes to the basic understanding of the failure mechanism of a bulk silicon anode electrode for lithium-ion batteries.     

Effects of Adding Sodium and Ethanol Inhibitor on Inhibiting H2 Evolution of Lithium Anode

在30℃的4mol/LLiOH电解质溶液中,通过测量锂负极的自腐蚀析氢速率、极化曲线、电化学阻抗谱及电位-时间曲线,研究了Na作为合金元素及乙醇作为添加剂对锂负极的共同抑制自腐蚀析氢作用。结果表明:合金元素Na及乙醇对阴阳极反应都起到了抑制作用,但是单一添加合金元素Na或者乙醇缓蚀剂对锂负极的抑氢作用不大,而当共同添加合金元素Na及乙醇时对锂负极的抑氢效率提高明显,缓蚀率超过了80%。另外,单独添加合金元素Na时,锂负极的放电性能极不稳定,而溶液中添加乙醇后有利于提高锂负极的放电稳定性。XRD结果表明,钠与锂形成了比较理想的固溶体。     

Challenges and strategies for ultrafast aqueous zinc-ion batteries

With the rising demand for fast-charging technology in electric vehicles and portable devices,significant efforts have been devoted to the development of the highrate batteries.Among numerous candidates,rechargeable aqueous zinc-ion batteries(ZlBs) are a promising option due to its high theoretical capacity,low redox potential of zinc metal anode and inherent high ionic conductivity of aqueous electrolyte.As the strong electrostatic interaction between Zn~(2+) and host generally leads to sluggish electrode kinetics,many strategies have been proposed to enhance fast(dis)charging performance.Herein,we review the state-of-the-art ultrafast aqueous ZIBs and focus on the rational electrode-designing strategies,such as crystal structure engineering,nanostructuring and morphology controlling,conductive materials introducing and organic molecule designing.Recent research directions and future perspectives are also proposed in this review.     

Ultrathin Al_2O_3-coated reduced graphene oxide membrane for stable lithium metal anode

Lithium(Li) metal has been considered as the most attractive anode materials for Li-ion batteries(LIBs)due to its high theoretic specific capacity. The formation of unstable solid electrolyte interphase(SEI) and dendritic Li on the metal anode, however, hindered its practical application. Herein, to address the issues, a Li-free electrode with ultrathin Al_2O_3 coated on reduced graphene oxide(rGO) membrane that covers a Cu foil current collector was developed. The composite electrode exhibits excellent interfacial protection of lithium metal deposited between Cu foil and rGO electrochemically. Firstly, it affords good Li~+ permeability from the electrolyte. Secondly, the ultrathin Al_2O_3 has sufficient mechanical strength to inhibit the penetration of Li dendrite. Li metal was observed uniformly deposited between rGO membrane and Cu collector, and stable cycle performance of Li plating/stripping with Coulombic efficiency of ~91.75% at the 100 th cycle is achieved in organic carbonate electrolyte without any additives.     

钛酸锂表面碳包覆改性研究进展

尖晶石结构的Li4Ti5O12由于电压平台平稳、循环寿命长、"零应变"和安全性高等优点,成为锂离子电池的热门负极材料。然而纯Li4Ti5O12本身为绝缘体,导电性很差,倍率性能不佳,这限制了它的实际应用。研究表明,对Li4Ti5O12表面进行碳包覆可以有效改善其电化学性能。结合最近国内外研究情况,综述了表面碳包覆对Li4Ti5O12负极材料改性的研究进展,分析了不同的碳包覆方法、碳层厚度、碳结构和碳含量对Li4Ti5O12/C复合材料电化学性能的影响,希望促进Li4Ti5O12/C复合电极材料在锂离子电池领域的应用。     

Pulsed laser deposited Sb2Se3 anode for lithium-ion batteries

Sb₂Se₃ thin film has been successfully fabricated by reactive pulsed laser deposition and was investigated for its electrochemistry with lithium for the first time. The reversible discharge capacities of Sb₂Se₃/Li cells cycled between 0.3 and 2.5 V were found in the range of 530.5–660.7 mAh g⁻¹ during the first 100 cycles. By using ex situ X-ray diffraction, transmission electron microscopy, and selected-area electron diffraction measurements, both classical alloying process and the selenylation/reduction of nanosized metallic antimony were proposed in the lithium electrochemical reaction of Sb₂Se₃. Sb₂Se₃ has high reversible capacity and good cycle performance, which makes it potential anode material for future lithium-ion batteries.     

Facile Preparation of NiO@graphene Nanocomposite with Superior Performances as Anode for Li-ion Batteries

Transition metal oxides gain considerable research attentions as potential anode materials for lithium ion batteries, but their applications are hindered due to their poor electronic conductivity, weak cycle stability and drastic volume change. Here, a NiO@graphene composite with a unique 3D conductive network structure is prepared through a simple strategy. When applied as anode material for Li-ion batteries, at 50 mA g^-1, the NiO@graphene displays a high reversible capacity of 1366 mAh g^-1 and a stable cyclability of 205 mAh g^-1 after 500 cycles. Even at a high rate of 10 A g^-1, it displays a favorable reversible capacity of 711 mAh g^-1. Remarkably, when it recovers back to 0.05 A g^-1, a reversible capacity of 1741 mAh g^-1 is achieved. Thus, the NiO@graphene composite with 3D structure shows good application prospects as an alternative anode for advanced lithium ion batteries.     

硅基锂离子电池负极材料研究进展

作为锂离子电池负极材料,硅基材料具有较高的理论比容量、适中的嵌/脱锂电位、与电解液反应活性低等特点,成为最有前景的锂离子电池负极材料之一。然而由于其巨大的体积效应和较低的导电性导致其商业化应用具有相当的挑战性。本文综述了近年来为改善硅基材料的缺点而做的一些研究,展望了硅基材料作为锂离子电池负极材料的发展趋势。