共查询到20条相似文献,搜索用时 32 毫秒
1.
近年来,在锂二次电池新材料的研发过程中逐渐建立了基于材料基因组思想的高通量计算理论工具与研究平台.在该平台上,通过将不同精度的计算方法组合,实现了基于离子输运性质的材料筛选;通过将信息学中数据挖掘算法引入高通量计算数据的分析,证实了材料大数据解读的可行性.上述平台实现了在锂电池固体电解质的高通量筛选、优化和设计上进行新材料研发的示范应用,通过高通量计算筛选获得了两种可用于富锂正极包覆材料的化合物Li_2SiO_3和Li2SnO_3,有效改善了富锂正极的循环稳定性;通过对掺杂策略的高通量筛选,获得了提高固体电解质β-Li_3PS_4离子电导率和稳定性的方案;通过高通量结构预测设计了全新的氧硫化物固体电解质LiAlSO;并在零应变电极材料结构与性能的构效关系研究中进行了大数据分析的尝试,分析了零应变电极材料的设计依据.上述材料基因组方法在锂电池材料研发中的应用为在其他类型材料研发中推广这种新的研发模式提供了可能. 相似文献
2.
Changqing Xiang Cheng-Wei Wu Wu-Xing Zhou Guofeng Xie Gang Zhang 《Frontiers of Physics》2022,17(1):13202
In recent years, lithium ion (Li-ion) batteries have served as significant power sources in portable electronic devices and electric vehicles because of their high energy density and rate capability. There are growing concerns towards the safety of Li-ion batteries, in which thermal conductivities of anodes, cathodes, electrolytes and separator play key roles for determining the thermal energy transport in Li-ion battery. In this review, we summarize the state-of-the-art studies on the thermal conductivities of commonly used anodes, cathodes, electrolytes and separator in Li-ion batteries, including both theoretical and experimental reports. First, the thermal conductivities of anodes and cathodes are discussed, and the effects of delithiation degree and temperature of materials are also discussed. Then, we review the thermal conductivities of commonly used electrolytes, especially on solid electrolytes. Finally, the basic concept of interfacial thermal conductance and simulation methods are presented, as well as the interfacial thermal conductance between separator and cathodes. This perspective review would provide atomic perspective knowledge to understand thermal transport in Li-ion battery, which will be beneficial to the thermal management and temperature control in electrochemical energy storage devices. 相似文献
3.
《中国物理 B》2018,(12)
This paper reviews the rapid progress in the field of high-throughput modeling based on the Materials Genome Initiative, and its application in the discovery and design of lithium battery materials. It offers examples of screening, optimization and design of electrodes, electrolytes, coatings, additives, etc. and the possibility of introducing the machine learning method into material design. The application of the material genome method in the development of lithium battery materials provides the possibility to speed up the upgrading of new candidates in the discovery of lots of functional materials. 相似文献
4.
5.
Jing Xu Peng Gu Jian Zhang Huaiguo Xue Huan Pang 《Particle & Particle Systems Characterization》2016,33(11):784-810
With the increasing energy demands for electronic devices and electrical vehicles, anode materials for lithium‐ion batteries with high specific capacity, good cyclic and rate performance become one of the focal areas of research. A class of them is the copper‐based nanomaterials that have thermal and chemical stability, high theoretical specific capacity, low price and environment friendliness. Now this kind of nanomaterials has been recognized as one of the critical materials for lithium‐ion batteries due to the predicted future market growth. Current status of different copper‐based materials which produced already are discussed. In this review, comprehensive summaries and evaluations are given in synthesis strategies, tailored material properties and different electrochemical performance. Recent progress of general copper‐based nanomaterials for lithium‐ion batteries is carefully presented. 相似文献
6.
Strategies to curb structural changes of lithium/transition metal oxide cathode materials & the changes' effects on thermal & cycling stability 下载免费PDF全文
Structural transformation behaviors of several typical oxide cathode materials during a heating process are reviewed in detail to provide in-depth understanding of the key factors governing the thermal stability of these materials. We also discuss applying the information about heat induced structural evolution in the study of electrochemically induced structural changes. All these discussions are expected to provide valuable insights for designing oxide cathode materials with significantly improved structural stability for safe, long-life lithium ion batteries, as the safety of lithium-ion batteries is a critical issue; it is widely accepted that the thermal instability of the cathodes is one of the most critical factors in thermal runaway and related safety problems. 相似文献
7.
J. Pröll R. KohlerM. Torge S. UlrichC. Ziebert M. BrunsH.J. Seifert W. Pfleging 《Applied Surface Science》2011,257(23):9968-9976
It is expected that cathodes for lithium-ion batteries (LIB) composed out of nano-composite materials lead to an increase in power density of the LIB due to large electrochemically active surface areas but cathodes made of lithium manganese oxides (Li-Mn-O) suffer from structural instabilities due to their sensitivity to the average manganese oxidation state. Therefore, thin films in the Li-Mn-O system were synthesized by non-reactive radiofrequency magnetron sputtering of a spinel lithium manganese oxide target. For the enhancement of the power density and cycle stability, large area direct laser patterning using UV-laser radiation with a wavelength of 248 nm was performed. Subsequent laser annealing processes were investigated in a second step in order to set up a spinel-like phase using 940 nm laser radiation at a temperature of 680 °C. The interaction processes between UV-laser radiation and the material was investigated using laser ablation inductively coupled plasma mass spectroscopy. The changes in phase, structure and grain shape of the thin films due to the annealing process were recorded using Raman spectroscopy, X-ray diffraction and scanning electron microscopy. The structured cathodes were cycled using standard electrolyte and a metallic lithium anode. Different surface structures were investigated and a significant increase in cycling stability was found. Surface chemistry of an as-deposited as well as an electrochemically cycled thin film was investigated via X-ray photoelectron spectroscopy. 相似文献
8.
Lithium ion batteries have become attractive for portable devices due to their higher energy density compared to other systems. With a growing interest to develop rechargeable batteries for electric vehicles, lithium iron phosphate (LiFePO4) is considered to replace the currently used LiCoO2 cathodes in lithium ion cells. LiFePO4 is a technically important cathode material for new-generation power lithium ion battery applications because of its abundance in raw materials, environmental friendliness, perfect cycling performance, and safety characteristics. However, the commercial use of LiFePO4 cathode material has been hindered to date by their low electronic conductivity. This review highlights the recent progress in improving and understanding the electrochemical performance like the rate ability and cycling performance of LiFePO4 cathode. This review sums up some important researches related to LiFePO4 cathode material, including doping and coating on surface. Doping elements with coating conductive film is an effective way to improve its rate ability. 相似文献
9.
A. Thi?en D. Ensling M. Liberatore Q.-H. Wu F. J. Fernandez Madrigal M. S. Bhuvaneswari R. Hunger W. Jaegermann 《Ionics》2009,15(4):393-403
Three different experimental routes to in situ characterization of electronic structure and chemical composition of thin film
cathode surfaces used in lithium ion batteries are presented. The focus is laid on changes in electronic structure and chemical
composition during lithium intercalation and deintercalation studied by photoelectron spectroscopy and related techniques.
At first, results are shown obtained from spontaneous intercalation into amorphous or polycrystalline V2O5 thin films after lithium deposition. Although this technique is simple and clean, it is nonreversible and only applicable
to the first lithium intercalation cycle into the cathode only to be applied to host materials stable in the delithiated stage.
For other cathode materials, as LiCoO2, a real electrochemical setup has to be used. In our second approach, the experiments are performed in a specially designed
electrochemical cell directly connected to the vacuum system. First experimental results of RF magnetron sputtered V2O5 and LiCoO2 thin film cathodes are presented. In the third approach, an all solid-state microbattery cell must be prepared inside the
vacuum chamber, which allows electrochemical processing and characterization by photoelectron spectroscopy in real time. We
will present our status and experimental difficulties in preparing such cells. 相似文献
10.
发射层厚度对反射式GaAs光电阴极性能的影响 总被引:5,自引:2,他引:3
通过求解扩散方程,推导了含有后界面复合速率的反射式GaAs光电阴极量子效率公式,并利用MBE在GaAs (100)衬底上外延生长了发射层厚度分别为1.6 μm、2.0 μm和2.6 μm,掺杂浓度为1×1019cm-3的三个反射式GaAs阴极样品,进行了激活实验.实验结果显示:随着发射层厚度的增加,阴极的长波量子效率和灵敏度都有所提高,而这种提高与阴极电子扩散长度的增长有关.同时,理论仿真研究发现,当后界面复合速率小于或等于105cm/s时,阴极发射层有一个最佳厚度,此时阴极灵敏度最高.后界面复合速率对阴极灵敏度在发射层厚度较小时影响较大,而随着厚度的增大阴极灵敏度最终趋于稳定. 相似文献
11.
采用电化学刻蚀方法,成功制备出单尖的六硼化镧、钼、钨及钨铼合金场发射冷阴极尖锥,并对这几种场发射单尖锥阴极的电子发射性能进行了测试比较.结果表明,LaB6作为场发射阴极,具有良好的发射性能和稳定性.在〈111〉面单晶LaB6基片上,用PECVD法沉积非晶硅作掩膜,制备出具有一定高度的LaB6微尖锥场发射阵列,结果发现,LaB6基底较为平整,尖锥阵列呈现出各向异性.该结论对LaB6材料在场发射阴极方面的进一步研究具有重要的指导意义. 相似文献
12.
《中国物理 B》2018,(12)
As an essential component of the Materials Genome Initiative aiming to shorten the period of materials research and development, combinatorial synthesis and rapid characterization technologies have been playing a more and more important role in exploring new materials and comprehensively understanding materials properties. In this review, we discuss the advantages of high-throughput experimental techniques in researches on superconductors. The evolution of combinatorial thin-film technology and several high-speed screening devices are briefly introduced. We emphasize the necessity to develop new high-throughput research modes such as a combination of high-throughput techniques and conventional methods. 相似文献
13.
LiMn2O4 is one of the most promising cathode materials for lithium secondary battery because of natural abundance of manganese in
the crust and its low toxicity to environment. Lithium ion can almost reversibly intercalate into or deintercalate from lithium
manganese spinel oxide LiMn2O4. A part of substitution of manganese with other transition metals brings the improvement of cycle life. We focused on the
local structure of the spinels and considered the effect of the local distortion on the cycle life of the spinel cathodes.
Paper presented at the 8th EuroConference on Ionics, Carvoeiro, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
14.
《Solid State Ionics》1988,27(4):251-258
Rechargeable solid state batteries utilizing lithium anodes, V6O13 composite cathodes and polymer electrolytes made from polyethylene oxide - LiCF3SO3 complex - were investigated at 100°C. The cells exhibited good cycling and reversibility. Optical and scanning electron microscopy were used to study the morphological changes taking place at the electrodes and electrolyte as a function of cycle number. Post-mortem examination of the cell materials indicated that the structures of lithium, electrolyte and cathode become finer grained and hence smoother. In addition the structures were more coherent. The cathode appeared to undergo a re-healing process during the early stage of cycling. The results indicate that the structures are consistent with one another and that long cycle life can be obtained with these types of cells. 相似文献
15.
《Journal of Electron Spectroscopy and Related Phenomena》1988,46(1):179-184
The present investigations were performed in order to study the electrochemical reduction of manganese dioxide in lithium cells. Samples were characterized by both ESCA and soft fluorescent X-ray emission measurements for several degrees of discharge. The influence of lithium incorporation in the cathodes at high degrees of discharge is discussed. 相似文献
16.
V. Baláš 《Czechoslovak Journal of Physics》1966,16(7):569-577
The study of the properties of a metal-dielectric-metal system in a strong electric field has so far led to heterogeneous results. Their agreement with theory is unsatisfactory or lacking entirely. The theoretical conceptions are based on the assumption of the field emission of electrons from the surface of metals to the conduction band of the dielectric and from there by passage through the second metal electrode to vacuum. A perfect dielectric is assumed here. This assumption is probably not fulfilled when realizing the cathodes, as can be estimated from a comparison of the technology of producing a dielectric, for example, with the preparation of intrinsic semi-conductors. The presence of defects in the dielectric layer may have a decisive influence on the properties of the cathodes. In this way we can obtain different results even when using the same materials for making the cathodes.The present paper deals with the influence of the thickness of the dielectric on the electrical properties of cathodes. Two different dielectrics were used, produced in different ways: a dielectric dependent on the metal electrode (oxidizing cathodes) and independent (evaporated cathodes).In conclusion, the author thanks L. Sodomka and K. Frainic for assistance in the experiments. 相似文献
17.
《Solid State Ionics》2006,177(26-32):2635-2638
In this paper, we report the latest findings for the new lithium vanadium fluorophosphate cathode material, LiVPO4F. High quality samples have been prepared using a carbothermal reduction approach and extensive electrochemical and DSC measurements have been performed. In graphite based lithium-ion cells, the LiVPO4F demonstrates reversible specific capacity behavior approaching theoretical. The lithium-ion system operates with an average discharge voltage around 4 V, low polarization and with good rate capability. These results indicate that the active material possesses exemplary electrochemical performance and may well be suitable as a replacement for LiCoO2 in commercial lithium-ion cells. DSC measurements on charged cathodes indicate the thermal stability behavior expected for a phosphate based active material. 相似文献
18.
Lithium transition-metal oxides used as intercalation compounds for rechargeable lithium batteries are widely studied in search
of structural stability and improved electrochemical performance. Cathode materials belonging to the 4-volt class electrodes
were synthesized by wet-chemistry methods, i.e., sol-gel, combustion or co-precipitation techniques. It is shown that synthesis
greatly affects the electrochemistry and cycle life characteristics of the cathodes. Extensive damage including local strain
variation, nanodomain formation, and changes in cation ordering, has been observed by local probes such as Raman and FTIR
spectroscopy. In this work we wish to show the relationship between the local cationic environment and electrochemical characteristics
of the 4-volt cathodes. Materials such as LiMn2O4, LiCoO2, LiNi1−yCoyO2, LiNi1−yCoyVO4, and LiMoVO6 are investigated. 相似文献
19.
Batteries of the size of microelectronic devices, less than 10 μm thick, are now being developed and built, using thin-film
deposition technologies, i.e., flash-evaporation, rf-sputtering and sol-gel technique, that are compatible with integrated
circuits. Their use in future micro-devices, microsensors, intergrated circuits, memories and very large-scale integration
are envisaged. Advances have been made particularly in the engineering of lithium/amorphous inorganic electrolyte/layered
compound cells. Physics of the solid-state microbatteries are reviewed and the latest advances presented. The adequacy and
efficiency of materials is examined. New optimized lithium microbatteries including transition-metal oxides as intercalation
cathodes, i.e., MoO3, V2O5, and V6O13 films are presented and their advantages are discussed in detail.
Paper presented at the 2nd Euroconference on Solid State Ionics, Funchal, Madeira, Portugal, 10–16 Sept. 1995. 相似文献