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碳作为单一元素可形成像零维碳纳米球、一维碳纳米管、二维石墨烯等多种碳纳米结构,它们在锂离子和锂硫电池中的表现也有所不同。需要阐明的是,碳纳米管和石墨烯由于具有以下缺点不适合直接作为锂离子或锂硫电池电极材料:(1)第一次不可逆容量大,首次充放电效率低;(2)在充放电曲线中电压滞后现象严重;(3)缺少稳定的电压平台;(4)容量衰减快。科学家们一直在为获得具有更高能量密度和更广阔应用前景的锂离子电池和锂硫电池而努力,由于可充电电池的性能主要取决于阴极和阳极的性能,因此,设计先进的电极材料以及制备具有特定成分和结构的电极成为近年来的研究热点。本文综述了碳纳米材料在构建高性能锂离子、锂硫电池电极材料和特定电极方面的作用。首先,从促进电子和离子传输、固定多硫化物位置以及缓冲体积膨胀三个方面讨论了碳纳米材料在修饰电活性材料的作用;其次,从作为导电添加剂、电流集流体和导电中间层三个方面讨论了碳纳米材料在最优化非活性组分的作用;然后,从作为非导电基体上的导电相、柔性电流集流体和自支撑复合电极三个方面讨论了碳纳米材料在柔性电池设计的作用。最后,本文对碳纳米材料的未来发展趋势作了概述,兼具多种功能的碳纳米材料被认为是今后的研究重点。 相似文献
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在能源危机的驱使下,电动汽车以及大型储能装置的快速发展需要高能量密度的锂二次电池来实现,锂硫电池硫电极因具有高理论比容量和能量密度而倍受关注。此外,单质硫具有储量丰富、成本低和无毒等优点,使得锂硫电池更具有商业竞争力,因此锂硫电池被认为是最有前途的二次电池之一。然而,锂硫电池依然存在电导率低、穿梭效应、体积膨胀和锂枝晶等问题,这限制其广泛应用。因此,研究者们从正极材料和夹层着手,除了对正极材料的导电性加以改善之外,主要从限制多硫化物的穿梭效应和缓冲正极体积膨胀进行研究。研究发现,相比碳基和聚合物基正极材料,金属化合物基正极材料可以更好地改善锂硫电池的倍率性能和循环稳定性。此外,金属化合物材料作为夹层时同样可以有效缓解这些问题,能够更好地抑制多硫化物的溶解和扩散,减少穿梭效应,提高锂硫电池的电化学性能。一些金属氧化物、金属硫化物、金属氮化物、金属磷化物等作为锂硫电池正极材料或夹层都取得了重大进展。对于部分极性金属化合物而言,其不仅能化学吸附充放电中间产物多硫化物,有效改善硫正极的循环稳定性,而且还能在氧化还原反应中表现出电催化活性,加快多硫化物的转化,提高硫正极的倍率性能。本文综述了近年... 相似文献
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随着可卷曲、可折叠、可穿戴及植入式柔性电子设备的出现,柔性自支撑电极材料的研究也备受瞩目。碳布是一种商用机织物,由于其高导电性、多孔网络、大表面积、良好的机械柔韧性和强度,被认为是构建柔性电极的优秀基材。近年来,各种活性物质(如金属单质、金属化合物及其复合物)直接生长或涂敷在碳布表面,当用作锂/钠离子电池负极时,它们表现出优异的机械稳定性和电化学性能。本文综述了这几类碳布基自支撑锂/钠离子电池负极材料的研究现状,重点介绍了碳布基自支撑锂/钠离子电池负极材料中的三个关键问题,具体包括碳布的预活化、活性物质在碳布上的负载形貌及电化学性能的表征,并展望了碳布基自支撑锂/钠离子电池负极材料所面临的挑战和机遇,这对于碳布用作锂/钠离子电池自支撑电极材料基底的研究具有一定的指导意义。 相似文献
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“双碳”战略要求新型储能器件具备更高的能量密度和更低的成本。锂硫电池因其低成本、环保和高比能(2600 Wh kg-1)等优势,而成为储能领域中最具潜能的电池体系,已受到了广泛的关注及研究。近年来,锂硫电池已取得了系列进展,但仍面临一些问题与挑战,包括硫固有的电荷传输效率差、可溶性多硫化物的“穿梭效应”、充放电过程中的剧烈体积膨胀及锂枝晶的生长等,这些问题会导致锂硫电池性能下降甚至失效。碳基硫宿主具有多孔、高电导、轻质、大比表面积等优点,能够有效解决以上难题,已成为锂硫电池研究领域中的重要方向。而碳材料种类繁多,有碳纳米纤维、碳纳米管、碳纳米片、碳纳米花等,不同形貌或具备不同纳米尺度维度的碳纳米结构对锂硫电池的性能具有不同的影响规律。基于此,本文围绕高性能锂硫电池碳基硫宿主进行综述,分类综述了一维、二维、及多维复合碳材料在锂硫电池领域的应用及其性能,阐述不同维度碳基硫宿主对其电化学性能的影响规律,并对未来的研究方向进行了一定的展望。 相似文献
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锂-空气电池具有极高的理论能量密度,成为下一代最有希望的电化学能量储存技术之一。锂-空气电池的性能主要取决于空气阴极表面发生的电化学反应,因此,合理设计具有高稳定性和可逆性的阴极是实现商业化可行的锂-空气电池的关键所在。然而,传统碳基电极的不稳定性导致的副反应会限制电池容量及其循环性能,因此,需要寻找能够替代碳基电极的新型电极。本文首先结合锂-空气电池的结构和阴极反应原理,提出了目前锂-空气电池面临的挑战,然后基于碳基阴极的不稳定性分析总结了设计稳定和可逆的锂-空气电池阴极的方法,最后提出了阴极催化剂的合理设计和催化机理的深入理解对锂-空气电池阴极的性能改善起着决定性作用的观点。 相似文献
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概述了锂二次电池隔膜材料的研究进展,介绍了锂二次电池隔膜材料的制备技术,包括相分离法、拉伸致孔法、熔融挤出/拉伸/热定型法和倒相法等,论述了影响电池性能的主要因素和表征隔膜性能的主要物理参数,总结了锂二次电池隔膜材料的研究近况和应用前景。 相似文献
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牛慧贤 《真空科学与技术学报》2006,26(5):392-396
真空作为低于一个标准大气压力的气体状态,能显示许多常压状态下无法出现的工艺新特点,已被人们在许多工业领域所应用。本文总括了真空技术及设备在全密封铅酸动力电池、MH—Ni动力电池、锂离子动力电池、燃料电池等制造过程中的应用和潜在应用,如真空混合、真空烧结、真空干燥、真空检漏、真空注液、真空封口、真空化成等。真空技术在动力电池制造过程中的广泛推广应用,必将推动动力电池制造的技术进步和发展。 相似文献
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There is rapid progress in the field of 3D printing technology for the production of electrodes, electrolytes, and packages of batteries due to the technique’s low cost, a wide range of geometries printable, and rapid prototyping speed by combining computer-aided design with advanced manufacturing procedures. The most important part of 3D printing applied in batteries is the printing of electrodes, electrolytes, and packages. These will affect the battery energy/power density. However, there are still several challenges that need to be overcome to print active and stable electrodes/electrolytes for energy storage systems that can rival that of the state-of-the-art. In this review, the printing materials, and methods for batteries from liquid to solid-state batteries are discussed and recent examples of this technique applied in high power/energy batteries are highlighted. This review for batteries will cover 3D printing technologies, printed cathode, and anode in conventional batteries, and printed solid-state electrolytes in solid-state batteries. The working principles, advantages, and limitations for solid-state batteries via the 3D printing method will be discussed before highlighting the printing materials for electrodes and electrolytes. We will then discuss how to modify the electrode and solid-state electrolyte to raise the electrochemical performance of solid-state batteries using 3D printing. Finally, we will give our insights into the future perspectives of this printing technique for fabricating batteries. 相似文献
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With the advent of intelligent electronics and green transportation systems, power sources with customized shape, flexibility, functionality and high security are indispensable. Innovative customizable solid-state batteries have recently been explored as a key-enabling technology to achieve this vision. Such custom-made power sources enable the monolithic integration of bipolar-stacked cells onto complex-shaped substrates, maximize space utilization of devices, meanwhile minimize the use of inactive components. Hence, they hold great potential in reducing the total weight of target electronic devices, extending their lifespan, and even as structural batteries to replace structural components in robotics, implants and electric vehicles. This review describes state-of-the-art of customizable solid-state batteries with a focus on fabrication techniques and corresponding material considerations. The relationship between the battery architecture design and form-factors of cells concerning their mechanical and electrochemical properties are in focus. The challenges and future developments of customizable solid-state batteries are elaborated with respect to their potential applications. Through novel material engineering, structural evolution, on-going extension of high-throughput fabrication technology, and integration of multifunctional systems, the customizable solid-state batteries will pave their way to power a growing share of smart electronics and modern transportation systems. 相似文献
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储氢合金表面包铜电极电化学性能研究 总被引:5,自引:0,他引:5
采用化学镀铜法对储氢合金进行表面包覆,用包覆粉制成的储氢电极,其放电容量,大电流充放电性能均得到了改善,1C全充放循环100次,容量仅下降5%,未包覆粉制成的电极,其容量相应地损失了21%,用此包覆粉组装有Ni/MH电池,1C/0.2C达到95%,1C全充放循环200周期,容量衰减20%,此外,初步探讨了储氢合金表面包铜的得与失。 相似文献
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Batteries are often packed together to meet voltage and capability needs.
However, due to variations in raw materials, different ages of equipment, and manual
operation, there is inconsistency between batteries, which leads to reduced available
capacity, variability of resistance, and premature failure. Therefore, it is crucial to pack
similar batteries together. The conventional approach to screening batteries is based on
their capacity, voltage and internal resistance, which disregards how batteries perform
during manufacturing. In the battery discharge process, real time discharge voltage
curves (DVCs) are collected as a set of unlabeled time series, which reflect how the
battery voltage changes. However, few studies have focused on DVC based battery
screening. In this paper, we provide an effective approach for battery screening. First, we
apply interpolation on DVCs and give a method to transform them into slope sequences.
Then, we use density-based spatial clustering of applications with noise (DBSCAN) for
denoising and treat the remaining data as input to the K-means algorithm for screening.
Finally, we provide the experimental results and give our evaluation. It is proved that our
method is effective. 相似文献
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Tobias Janoschka Martin D. Hager Ulrich S. Schubert 《Advanced materials (Deerfield Beach, Fla.)》2012,24(48):6397-6409
Our society's dependency on portable electric energy, i.e., rechargeable batteries, which permit power consumption at any place and in any time, will eventually culminate in resource wars on limited commodities like lithium, cobalt, and rare earth metals. The substitution of conventional metals as means of electric charge storage by organic and polymeric materials, which may ultimately be derived from renewable resources, appears to be the only feasible way out. In this context, the novel class of organic radical batteries (ORBs) excelling in rate capability (i.e., charging speed) and cycling stability (>1000 cycles) sets new standards in battery research. This review examines stable nitroxide radical bearing polymers, their processing to battery systems, and their promising performance. 相似文献
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