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静电纺丝法由于具有工艺简单、功能多样等优点,是一种重要的制备一维锂钠离子电池纳米结构电极材料的方法。目前,已有大量利用静电纺丝技术制备高性能电极材料的研究报道,但具有系统性和针对性的综述论文尚十分有限。碳材料是最早被研究且已实现商业化的锂离子电池负极材料,硅材料则是理论容量最高的负极材料,因此,两者一直是学术界和工业界关注的重点;但碳材料理论容量低和硅材料体积变化大的问题严重阻碍了各自更广泛的实际应用。静电纺丝技术被证明是一种可以解决上述问题的十分有效的方法。因此,本文系统地综述了静电纺丝法制备的硅基和碳基纳米纤维在锂钠离子电池负极材料上的应用和发展,重点从静电纺丝原理、硅碳材料的设计及合成、结构的调控与优化、复合材料的制备到电化学性能的提高等方面作了详细介绍和讨论,同时也指出静电纺丝法在大规模生产中的不足及未来可能的发展方向。希望此综述可以为先进储能材料(尤其是硅基和碳基纳米电极材料)的设计和制备提供一些有益的指导和帮助。 相似文献
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纳米石墨化碳因其优异的导电、导热及力学性能近年来备受重视,并在锂离子电池体系中得到广泛运用。纳米石墨化碳具有的优异电学性能及纳米尺度结构特征使其在解决锂离子电池中高导电性、导热性、充放电过程中的柔性及结构稳定性等方面发挥了重要作用。本文综述了近年来纳米石墨化碳在锂离子电池应用中的最新进展和研究热点,包括纳米石墨化碳在锂离子电池中直接充当高容量负极材料,纳米石墨化碳作为高性能骨架材料为电极提供导电及力学网络,与硅、金属氧化物等高容量电极材料复合形成同轴、核壳等结构的高容量电极材料甚至柔性电极等。如何进一步认识纳米石墨化碳储锂机制,发展其精确可控制备科学和工程技术,进而在三维尺度上构建高效的锂离子电池电极材料结构仍是未来的重点研究方向。 相似文献
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相变储热材料是指由于材料相转变吸热或放热过程而本身温度不变,从而实现储能的一类功能材料。有机相变材料如石蜡类、多元醇类及硬脂酸类因无腐蚀、无毒、无过冷等优点已成为重要的低温相变储热材料。这类材料通过固-液相变调节微环境温度,可用于服装、建筑及军事等方面,市场前景广阔。但相变过程易泄漏及热导率低等限制其了实际应用。静电纺丝是有效解决该问题的方法之一,高分子在高压静电作用下形成纤维,相变材料被高分子作为支撑材料所固定,很好地解决了泄漏问题。此外,通过加入高热导率材料可提高相变材料的吸放热速率,改善有机相变材料热导率低的问题。本文总结了近年来静电纺丝用于制备相变调温纤维的研究报道,分析了目前该类材料的研究现状,并讨论未来研究方向。为储热相变材料的进一步研究提供参考。 相似文献
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李亚飞贺劲鑫郑媛媛靳承铀缪永华薛驰 《储能科学与技术》2017,(S1):21-25
本文首先以SiO、沥青为原料,制备了SiO/C复合材料.然后以SiO/C复合材料,硝酸铝,氨水,尿素为原料,利用水浴加热和高温热处理的方法,制备出了Al2O3-SiO/C复合材料.采用激光粒度分析、比表面积测试仪、XRD、SEM对样品进行了物相结构分析和微现形貌的表征测试.电化学测试表明:加入尿素的A12O3-SiO/C复合材料具有最佳电化学性能,首次效率高达74.81%,充电比容量为1436.4mA·h/g,表现了优异的电化学性能. 相似文献
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利用有机溶剂法回收了废旧锂离子电池中的钛酸锂负极材料,并对回收的钛酸锂材料的结构、形貌和电化学性能进行了测试。XRD结果表明,材料除炭后添加适量锂源进一步合成得到的产物具有尖晶石结构,且不含其他的杂质。SEM图像显示,其颗粒分布均匀、无团聚现象。EIS结果表明,最终回收的钛酸锂电极材料比未添加锂源进行煅烧处理的材料具有较小的电荷转移阻抗和较高的锂离子扩散系数。在0.1 C倍率下,经过100次循环后其容量保持率为92.4%,具有优异的循环稳定性和可逆性,可以实现循环利用。 相似文献
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硅因其超高的理论比容量,有望成为下一代高性能锂离子电池的负极材料.硅在充放电过程中的剧烈体积膨胀会引起颗粒粉化、SEI膜过量生长以及活性物质失去电接触等问题,最终导致容量快速衰减.开发新型硅负极黏结剂和硅碳复合是提升硅负极性能的重要策略.生物高分子材料成本低、环境友好且富含有机官能团,非常适合用来开发低成本、高性能硅负极黏结剂,也适合作为碳前体合成硅碳复合材料.本文综述了近年来基于生物高分子的硅负极黏结剂和以生物高分子为碳前体的硅碳复合材料的研究进展.本文重点介绍了基于海藻酸钠、壳聚糖、淀粉的硅负极黏结剂,总结出生物高分子基黏结剂的主要改性方法有接枝特殊官能团、与其他聚合物共混或交联.基于这些改性方法,可分别提升黏结剂的黏附性、导电子或离子能力以及实现3D网络结构的构建.本文重点归纳了以纤维素、壳聚糖、淀粉、木质素为碳前体的硅碳复合材料,分别介绍了这些复合材料的性质、结构特点,及其对电化学性能的影响.基于以上分析,本文也指出了当前基于生物高分子的硅负极黏结剂和以生物高分子为碳前体的硅碳复合材料的不足,为其下一步发展指明了方向. 相似文献
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作为一种具有前景的能量存储系统,锂离子电池需要进一步提高能量密度、功率密度、可靠性和循环稳定性,以满足不断增长的大型能源存储、电动汽车和便携式电子设备需求。当前对锂离子电池的实验研究仍然面临多个挑战,这些挑战包括电解液的导电性和安全性、高能量负极的沉积-剥离机制的优化、高能量正极的循环电压和容量维持、高电流条件下的界面极化和容量释放,以及在极端电流-温度-针刺条件下的热失控管理等问题。这些问题涉及到电-化-力-热等多个场的耦合作用,需要进行协同优化处理。COMSOL Multiphysics提供了一种可行的工具,通过求解多物理场耦合的连续方程,能够同时考虑载流子浓度、电流密度、电-化学势、温度、应力/应变和几何形态等综合信息的演化。本文概述了该工具在锂离子电池的电解液、负极和正极设计等方面的研究,并聚焦于多场耦合对电池性能的综合影响、多场耦合模拟方法以及理论模拟与实验表征的结合。最后,本文对理论与实验联合研究中的多场和多尺度问题进行了展望。 相似文献
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郑瀚来沛霈田晓华孙卓张哲娟 《储能科学与技术》2023,(1):23-34
以光伏电池生产废料中的大尺寸硅颗粒(200~800 nm)为原料,水性聚氨酯(PU)和聚苯胺(PANI)作为碳源,通过液相包裹法和低温热解法制备了不同结构碳复合的硅碳负极材料(SPU与SPU#PANI),分别研究了复合碳含量、微结构与元素掺杂对负极电化学性能的影响。SPU负极中碳复合量低,首次放电比容量高达2193.6 mAh/g,但循环稳定性差。经二级碳复合后的SPU#PANI导电性提高,在多孔碳微结构支撑作用下,不仅获得了较高的放电比容量(1488.8 mAh/g),而且经100次循环后SPU#PANI放电比容量保持在756.8 mAh/g以上,表现出良好的倍率性能。研究结果表明,大尺寸硅颗粒表面复合了具备多孔结构的碳后,不仅为硅充放电过程中的膨胀提供了缓冲,也为锂离子传输提供通道,有效地提升了硅基负极的电化学性能和稳定性。本工作采用的多级碳低温热解复合方法,可为锂离子电池硅基负极产业化技术发展提供重要的借鉴。 相似文献
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Lin Zou Lin Gan Feiyu Kang Mingxi Wang Wanci Shen Zhenghong Huang 《Journal of power sources》2010,195(4):1216-1220
Sn/C non-woven film has been prepared by electrospinning and carbonization treatment. Investigation of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM) indicate that the film is formed by non-woven fibers. The fibers consist of amorphous carbon and homogeneously dispersed tin particles, which are extremely tiny (around 1 nm). However, partial tin particles are oxidized when the film is kept in the air, which is confirmed by X-ray diffraction (XRD). The XRD measurement also suggests that the tin oxides completely decompose to pure tin after several electrochemical cycles. The reversible capacity of the film in the 20th cycle is 382 mAh g−1, which is 96.7% of the capacity in the first cycle. Such Sn/C non-woven film could be a promising anode material in lithium ion batteries. 相似文献
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锂离子电容器是一种介于超级电容器和锂离子电池之间的新型储能器件,具有高能量密度、高功率密度以及长循环寿命等优点,在电动汽车、轨道交通、智能电网、可移动电子设备等领域具有非常广泛的应用前景。金属氧化物具有脱/嵌锂能力优异,理论比容量普遍较高,而且自然资源丰富、环境友好的优点,是一类理想的锂离子电容器负极材料,但电子导电率不高,脱/嵌锂过程中不可逆体积畸变较大,影响了其商业化的应用。本文综述了金属氧化物负极材料的制备方法,并分析了其作为锂离子电容器负极材料的电化学性能与优缺点,最后展望了金属氧化物负极材料未来的发展方向。 相似文献
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Bing SunZhixing Chen Hyun-Soo KimHyojun Ahn Guoxiu Wang 《Journal of power sources》2011,196(6):3346-3349
MnO/C core-shell nanorods were synthesized by an in situ reduction method using MnO2 nanowires as precursor and block copolymer F127 as carbon source. Field emission scanning electron microscopy and transmission electron microscopy analysis indicated that a thin carbon layer was coated on the surfaces of the individual MnO nanorods. The electrochemical properties were evaluated by cyclic voltammetry and galvanostatic charge-discharge techniques. The as-prepared MnO/C core-shell nanorods exhibit a higher specific capacity than MnO microparticles as anode material for lithium ion batteries. 相似文献
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We report a one-pot method to synthesize CoO/C hybrid microspheres via a solvothermal approach. The resulting samples were characterized by thermogravimetric analysis, X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy and charge–discharge test. X-ray diffraction analysis revealed that the as-prepared samples possessed poor crystalline characteristics and were transformed into crystalline materials after thermal treatment. Field-emission scanning electron microscope images showed that the surfaces of these as-prepared spheres were relatively smooth and of about 2.2 μm in diameter. The diameters of the spheres kept unchanged after being annealed at 800 °C in a high purity nitrogen atmosphere under ambient pressure. The preliminary electrochemical test found that the annealed CoO/C hybrid microspheres exhibited an ultrahigh initial discharge capacity of 1481.4 mAh g−1 in the potential range of 3.0–0.01 V. This value was much higher than that of CoO nanoparticles. Although the capacity of the second discharge cycle decayed to 506.2 mAh g−1, the annealed CoO/C hybrid microspheres anode exhibited very stable reversible capacity at about 345 mAh g−1 only after 10 cycles. This rapid stabilization ability was attributed to the matrix effect of carbon, which may effectively prevent the aggregation of small particles during charging–discharging process. 相似文献
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Lifeng CuiJian Shen Fangyi ChengZhanliang Tao Jun Chen 《Journal of power sources》2011,196(4):2195-2201
The SnO2@polypyrrole (PPy) nanocomposites have been synthesized by a one-pot oxidative chemical polymerization method. The structure, composition, and morphology of the as-prepared SnO2@PPy nanocomposites are characterized by XRD, FTIR, TG, SEM, and TEM. Electrochemical investigations show that the obtained SnO2@PPy nanocomposites exhibit high discharge/charge capacities and favorable cycling when they are employed as anode materials for rechargeable lithium-ion batteries. For the SnO2@PPy nanocomposite with 79 wt% SnO2, the electrode reaction kinetics is demonstrated to be controlled by the diffusion of Li+ ions in the nanocomposite. The calculated diffusion coefficiency of lithium ions in the SnO2@PPy nanocomposite with 79 wt% SnO2 is 6.7 × 10−8 cm2 s−1, while the lithium-alloying activation energy at 0.5 V is 47.3 kJ mol−1, which is obviously lower than that for the bare SnO2. The enhanced electrode performance with the SnO2@PPy nanocomposite is proposed to derive from the advantageous nanostructures that allow better structural flexibility, shorter diffusion length, and easier interaction with lithium. 相似文献
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The tin/graphite/silver (Sn/G/Ag) composite was prepared by high-energy mechanical milling (HEMM) for the first time. The composite powders consisted of electrochemically active Sn, Ag4Sn phases which were uniformly distributed on the surface of the graphite particles. The formation of Ag4Sn alloy phase and the uniform distribution of the active particles could accommodate the large volume changes during cycling. X-ray diffraction (XRD), high-resolution transmission electron microscope (HRTEM) and scanning electron microscopy (SEM) were used to determine the phases obtained and to observe the microstructure and dispersion of particles. In addition, cyclic voltammetry (CV) and galvanostatic discharge/charge tests were carried out to characterize the electrochemical properties of the composite. The composite electrodes exhibited an initial capacity of 1154 mAh g−1 and maintained a reversible capacity of above 380 mAh g−1 for more than 100 cycles. 相似文献
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Q. SiK. Hanai T. IchikawaA. Hirano N. ImanishiO. Yamamoto Y. Takeda 《Journal of power sources》2011,196(16):6982-6986
The electrochemical performance of a composite of nano-Si powder and a pyrolytic carbon of polyvinyl chloride (PVC) with carbon nanofiber (CNF) was examined as an anode for solid-polymer lithium-ion batteries. Nano-Si powder was firstly coated with carbon by pyrolysis of PVC and then mixed with CNF (referred to as Si/C@CNF) using a rotation mixer. The composite exhibited good cycling performance, but suffered from a large irreversible capacity loss of which the retention was less than 60%. In order to reduce the loss, a thin lithium sheet was attached to the Si/C@CNF electrode surface as a reducing agent. The irreversible capacity of the first cycle was lowered to as much as 0 mAh g−1 and after the third cycle, the lithium insertion and extraction efficiency was almost 100%. A reversible capacity of more than 1000 mAh g−1 was still maintained after 40 cycles. 相似文献
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A novel silicon/graphite material prepared by a new process, in which a gelatinous silicon precursor is deposited on porous natural graphite, is introduced. The obtained composite material provides an excellent cycling stability, high coulombic efficiencies and a good rate capability. Morphology and structure of the new material were examined by SEM/TEM measurements using focused ion beam technique for sample preparation. 相似文献