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锂离子电池是目前发展最快的化学储能电源,使用固态电解质的固态锂离子电池相比传统液态电解质锂离子电池能量密度更高,安全性更好,是下一代锂离子电池的发展方向。石榴石结构Li7La3Zr2O12(LLZO)固态电解质凭借较高的离子电导率、宽的电化学窗口及优异的稳定性,成为了最具商业前途的固态电解质之一。本文从石榴石结构LLZO电解质的发展脉络出发,剖析了石榴石结构LLZO电解质的结构特性、离子传导机制及其具有的高的结构稳定性和离子传导能力的本源,在此基础上综述了石榴石LLZO电解质的单元、双元、多元体相掺杂改性以提升电解质本征离子电导率,第二相掺杂改性以提升电解质的抗锂细丝生长能力、陶瓷致密度等性能,最后对石榴石结构LLZO电解质材料掺杂改性方向进行了分析和展望,为推动全固态锂离子电池电解质的发展提供参考。 相似文献
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影响锂离子电池安全性的因素 总被引:12,自引:0,他引:12
锂离子电池的安全性一直是锂离子电池 ,特别是大型锂离子电池研制、生产、使用中的关键性问题 ,通过对锂离子电池的材料、制造工艺以及使用条件等方面的探讨 ,分析影响锂离子二次电池安全性的各种因素 相似文献
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0引言为解决目前日益严重的汽车尾气排放对城市空气造成污染问题,作为绿色能源的锂离子电池已成为动力电池的首选对象。国际上,高容量、大功率锂离子电池早于1995年已开始研制。1996年,我国天津电源研究所也进行了大容量锂离子蓄电池及电池组的探索[1]。目前,锂离子电池的正极材料是制约其大规模推广应用的关键。现研究的正极材料主要包括具有层状结构的LiCoO2,LiN iO2和LiM nO2及具有尖晶石结构的LiM n2O4等。其中LiC oO2作为目前唯一已经商业化的正极材料具有理论容量高、可循环性能好等优点,但因Co资源的相对缺乏导致其价格高昂。… 相似文献
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近几年,应用碳材料负极和有机电解液的液态锂离子电池(LIBs)的弊端日益凸显,电解液泄漏和过热燃烧等安全事故频发。另外,传统的LIBs也无法满足当今社会对高能量密度电池的需求。由于上述LIBs存在的诸多缺点,市场急需开发兼顾高能量密度与高安全性能的新型电池,现已发现可通过引入固态电解质的途径来实现。固态锂电池(SSLBs)相较于传统的LIBs,具有较高的能量密度、较宽的工作温度范围和更高的安全性。其中,固态电解质作为固态电池的重要元件之一,对电池性能的影响至关重要。石榴石Li7La3Zr2O12凭借其高锂离子电导率(1×10-4~1×10-3 S/cm)、宽电化学窗口(9 V)以及对锂负极的高稳定性等优点,在众多固态电解质中脱颖而出。本综述就提高石榴石基电解质锂离子电导率的研究予以总结:首先,介绍了Li7La3Zr2O12晶体结构并分析了结构与电导率之间的关系;然后,综... 相似文献
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采用热分解氧化法,在Ni基体上制备以PdO为中间层、RuO2为活性层的Ni/PdO/RuO2复合型活性阴极,并通过XPS、XRD、能量色散X荧光(EDXRF)、SEM、极化曲线、循环伏安法和交流阻抗谱等表征其组成、结构与电化学性能。结果表明,Pd和Ru分别以PdO和RuO2的形式存在于Ni/PdO/RuO2复合型活性阴极中,其含量分别为1.25wt%和1.71wt%;在363K、11mol·L-1NaOH溶液、3kA·m-2电流密度下,Ni/PdO/RuO2复合型活性阴极的析氢过电位比Ni电极和Ni/RuO2电极分别低371和125mV;循环伏安法循环72h后,该复合型活性阴极双电层电容值减小30.6%,比Ni/RuO2电极表层结构更稳定;Ni/PdO/RuO2复合型活性阴极的表面粗糙度大且无明显的裂纹存在,与纯镍电极相比,该复合型活性阴极比表面积增加了31.12倍。 相似文献
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LiNi_(0.8-y)Ti_yCo_(0.2)O_2电极材料中钛离子掺杂作用机理的研究 总被引:1,自引:0,他引:1
应用恒流充放电、非现场X射线粉末衍射 (ex situXRD)、电化学交流阻抗 (EIS)、程序控温脱附 质谱联用(TPD MS)等实验方法研究LiNi0. 8-yTiyCo0. 2O2电极材料钛离子的掺杂作用机理.结果表明,掺钛后的电极材料于充放电过程中的结构相变和晶格的膨胀收缩受到抑制,在高电位下的界面反应活性减弱,从而减小了由结构变化和界面反应引起的容量损失;同时,钛的掺杂增强了电极材料在脱锂状态下的结构稳定性,抑制了电极材料和电解液的分解或氧化反应,以上两个方面分别改善并提高了电极材料的充放电循环性能及其热稳定性. 相似文献
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Shiqiang Liu Tianyi Ma Zhen Wei Guangli Bai Huitian Liu Dapeng Xu Zhongqiang Shan Fang Wang 《Journal of Energy Chemistry》2021,(1)
Lithium-ion batteries are widely used in electric vehicles and electronics, and their thermal safety receives widespread attention from consumers. In our study, thermal runaway testing was conducted on the thermal stability of commercial lithium-ion batteries, and the internal structure of the battery was analyzed with an in-depth focus on the key factors of the thermal runaway. Through the study of the structure and thermal stability of the cathode, anode, and separator, the results showed that the phase transition reaction of the separator was the key factor affecting the thermal runaway of the battery for the condition of a low state of charge. 相似文献
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Lithium ion batteries (LIBs) have broad applications in a wide variety of a fields pertaining to energy storage devices. In line with the increasing demand in emerging areas such as long-range electric vehicles and smart grids, there is a continuous effort to achieve high energy by maximizing the reversible capacity of electrode materials, particularly cathode materials. However, in recent years, with the continuous enhancement of battery energy density, safety issues have increasingly attracted the attention of researchers, becoming a non-negligible factor in determining whether the electric vehicle industry has a foothold. The key issue in the development of battery systems with high specific energies is the intrinsic instability of the cathode, with the accompanying question of safety. The failure mechanism and stability of high-specific-capacity cathode materials for the next generation of LIBs, including nickel-rich cathodes, high-voltage spinel cathodes, and lithium-rich layered cathodes, have attracted extensive research attention. Systematic studies related to the intrinsic physical and chemical properties of different cathodes are crucial to elucidate the instability mechanisms of positive active materials. Factors that these studies must address include the stability under extended electrochemical cycles with respect to dissolution of metal ions in LiPF6-based electrolytes due to HF corrosion of the electrode; cation mixing due to the similarity in radius between Li+ and Ni2+; oxygen evolution when the cathode is charged to a high voltage; the origin of cracks generated during repeated charge/discharge processes arising from the anisotropy of the cell parameters; and electrolyte decomposition when traces of water are present. Regulating the surface nanostructure and bulk crystal lattice of electrode materials is an effective way to meet the demand for cathode materials with high energy density and outstanding stability. Surface modification treatment of positive active materials can slow side reactions and the loss of active material, thereby extending the life of the cathode material and improving the safety of the battery. This review is targeted at the failure mechanisms related to the electrochemical cycle, and a synthetic strategy to ameliorate the properties of cathode surface locations, with the electrochemical performance optimized by accurate surface control. From the perspective of the main stability and safety issues of high-energy cathode materials during the electrochemical cycle, a detailed discussion is presented on the current understanding of the mechanism of performance failure. It is crucial to seek out favorable strategies in response to the failures. Considering the surface structure of the cathode in relation to the stability issue, a newly developed protocol, known as surface-localized doping, which can exist in different states to modify the surface properties of high-energy cathodes, is discussed as a means of ensuring significantly improved stability and safety. Finally, we envision the future challenges and possible research directions related to the stability control of next-generation high-energy cathode materials. 相似文献
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It is a technological problem of LiNiO2 cathode material for lithium-ion secondary batteries because of the difficult preparation and hard purification, instable performance, remarkable capacity fading at initial discharge, worse thermal stability and safety of Ni-series cathode materials,and it is also the key factor of hindering LiNiO2 cathode material from practical applications.Recently, by doping some metal cations such as Co, Mn, Mg, Al, Cr and so on[1-5] into LiNiO2, the preparation difficulty and the purification hardness can be obviously improved, and the initial irreversible discharge capacity can be reduced, and the ratio of the initial discharge to charge capacity can be enhanced. But the cyclic stability, thermal stability and safety of LiNiO2 are not enough to satisfy the demand of commercial use.At present, the synthesis of LiNiO2 cathode material must be sintered under oxygen atmosphere in most cases, and the improved effect of fluoride doping on the electrochemical properties of LiNiO2 has seldom been reported in the literatures.In this paper, the cobalt cation and fluorine anion co-doping cathode materials Li1+δNi1-xCoxO2-yFy( 0≤δ≤0.2, 0≤x≤0.5, 0≤y≤0.1 ) were synthesized by solid state reaction method at 650℃ ~750℃ under air atmosphere, and characterized by XRD、 SEM、 TEM、 BET、 laser particle-size distribution measurement and electrochemical performance testing, the effect of different nickel sources on the properties of as-synthesized cathode materials was investigated. The results demonstrated that the cobalt and fluorine ions co-doping cathode materials Li1+δNi1-xCoxO2-yFy have complete layered structure, uniform surface morphology and better particle-size distribution as well as excellent electrochemical performances. At 20~25℃, 0.15~0.25mA charge and discharge current,4.25~2.70V cut-off voltage, 0.2~0.5C charge and discharge rate and 0.2~0.5 mA/cm2 current density,LiNi0.8Co0.2O1.95F0.05 cathode material has higher initial charge and discharge capacity and better cyclic properties which can be mainly attributed to the doping of the higher electronegativity fluorine which improves the structural stability and the synergistic reaction of cobalt and fluorine ions co-doping on the cathode materials. Under the above conditions, the initial charge and discharge capacity of LiNi0.8Co0.2O1.95F0.05 is 165.70mAh/g and 146.10mAh/g, respectively. After 50 cycles, it has more than 140mAh/g of discharge capacity and displays preliminary application possibility in the future. 相似文献
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The phosphorus-containing additives can help for forming a stable solid electrolyte interface film on the NCA cathode, thus enhance the thermal stability of the electrolyte and cycle performance of the battery. 相似文献
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《中国科学:化学(英文版)》2017,(9)
Nickel-rich layered materials,such as LiNi_(0.8)0Co_(0.15)Al_(0.05)O_2(NCA),have been considered as one alternative cathode materials for lithium-ion batteries(LIBs) due to their high capacity and low cost.However,their poor cycle life and low thermal stability,caused by the electrode/electrolyte side reaction,prohibit their prosperity in practical application.Herein,AlPO4 has been homogeneously coated on the surface of NCA via wet chemical method towards the target of protecting NCA from the attack of electrolyte.Compared with the bare NCA,NCA@AlPO_4 electrode delivers high capacity without sacrificing the discharge capacity and excellent cycling stability.After 150 cycles at 0.5 C between 3.0-4.3 V,the capacity retention of the coated material is 86.9%,much higher than that of bare NCA(66.8%).Furthermore,the thermal stability of cathode is much improved due to the protection of the uniform coating layer on the surface of NCA.These results suggest that AlPO4 coated NCA materials could act as one promising candidate for next-generation LIBs with high energy density in the near future. 相似文献
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镍基层状氧化物NaNiO2钠离子电池材料具有高电压和高容量的特性,且制备方法较为简单,但姜-泰勒(Jahn-Teller)效应使其在高倍率循环下容量较低以及在高电压(4.5 V)下无法稳定循环。通过调节溶胶-凝胶工艺的条件,设计、合成了Na2/3Mn1/3Bi1/3Ni1/3O2片层状金属氧化物,并将其作为正极活性材料,在空气环境中组装成钠离子电池,进行电化学测试,考察Bi、Mn掺入量对电池电化学影响。研究结果表明:当金属Mn和Bi共掺时,在1.2~4.5 V宽电压范围内,电池在循环50周后容量为90.39 mAh·g-1。在2.0~4.0 V电压范围内1.0C (115 mA·g-1)倍率下恒流充放电50周后的容量保持率为96.96%,循环850周后的保持率为80.15%,具有良好的循环稳定性和安全性。 相似文献
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镍基层状氧化物NaNiO2钠离子电池材料具有高电压和高容量的特性,且制备方法较为简单,但姜-泰勒(Jahn-Teller)效应使其在高倍率循环下容量较低以及在高电压(4.5 V)下无法稳定循环。通过调节溶胶-凝胶工艺的条件,设计、合成了Na2/3Mn1/3Bi1/3Ni1/3O2片层状金属氧化物,并将其作为正极活性材料,在空气环境中组装成钠离子电池,进行电化学测试,考察Bi、Mn掺入量对电池电化学影响。研究结果表明:当金属Mn和Bi共掺时,在1.2~4.5 V宽电压范围内,电池在循环50周后容量为90.39 mAh·g-1。在2.0~4.0 V电压范围内1.0C (115 mA·g-1)倍率下恒流充放电50周后的容量保持率为96.96%,循环850周后的保持率为80.15%,具有良好的循环稳定性和安全性。 相似文献