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1.
锂离子电池炭负极材料研究现状与发展   总被引:1,自引:0,他引:1  
综述了近年来各种炭材料作为锂离子电池负极材料的新进展,着重分析了石墨、焦炭和难石墨化炭在放电容量、不可逆容量损失、充放电电位和充放电速率等主要性能上的差异以及与其结构之间的联系;指出以PAS为代表的热解炭(低于800℃)和纳米炭材料将是锂离子电池负极材料的发展方向。  相似文献   

2.
石墨类碳负极材料作为电化学嵌锂宿主材料的研究一直是锂离子电池负极材料研究的重点。本文简述了石墨作为锂离子电池负极材料的结构,分析了石墨作为负极材料的优缺点,综述了石墨负极材料的改性方法及其研究进展,指出了石墨改性的发展方向。通过改性处理可以提高可逆比容量和首次库仑效率,改善其倍率性能和循环稳定性,有效改善石墨电极的综合电化学性能。  相似文献   

3.
商业化的锂离子电池石墨负极材料的研究进展   总被引:5,自引:0,他引:5  
综述了锂离子电池石墨负极材料的研究进展,对MCMB、天然石墨与人造石墨、炭纤维为代表的石墨负极材料目前的研究和应用现状进行了详细的论述,并对石墨类炭负极的发展作了展望。  相似文献   

4.
锂离子电池因其质量轻,能量密度高等优良性能,是近几年来电化学界研究的热点。但锂离子电池用石墨作负极还存在一些问题,需要对石墨改性处理。本文介绍了石墨的一种改性方法:沥青包覆石墨法,可有效降低石墨的比表面积,从而大幅度提高了石墨负极材料的首次可逆容量和库仑效率,改善电池的循环性能等。  相似文献   

5.
综述了锂离子二次电池用炭负极材料:石墨、各种体系炭纤维、石墨化中间相炭微球、焦炭、热解炭的结构与电性能等特点,并通过比较选择出最适宜的炭负极材料。  相似文献   

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文摘     
<正>锂离子电池负极用纤维状炭材料[刊,中]/楠顶,黄正宏,康飞宇,等//新型炭材料,2015(1):1~11纤维状炭材料有各种尺度和形貌,由于成本和性能缺乏竞争力,制约其在锂离子电池负极材料中的应用。随着纳米技术的发展,一些改性后的新型炭纤维表现出良好的负极材料性能。文章综述了近年各种纤维状炭材料用作锂离子电池负极材料的国内外研究进展。依据纤维状炭材料的结构、性能及其研究思路,分别归纳了石墨纤维、炭纤维及具有各种  相似文献   

7.
摘锂离子电池由于具有高能量密度、长循环寿命等优点,被广泛应用于电动汽车、储能、便携式电子产品等领域。电极材料是制约锂离子电池发展的关键。碳材料因为容量高、放电平台低、来源广泛等优点成为目前商业化锂离子电池负极材料的主流,主要包括石墨、无定形碳。文章总结了锂离子电池碳负极材料的发展历史,重点对石墨、无定型碳的储锂机理进行了分析。  相似文献   

8.
刘海丰  何莹  张大奎 《炭素》2021,(2):9-12,8
本文采用自制负极材料焦,对比国内外主要锂离子电池负极材料厂家所用焦炭,通过破碎、球磨、煅烧、石墨化等工艺制成人造石墨材料.从表面形貌、粒度分布、比表面积、石墨化度、首次库伦效率、首次充放电比容量等指标进行分析评价.  相似文献   

9.
陈瑞峰 《化学工业》2013,31(5):29-30
随着纯电动汽车(EV)、混合动力汽车(HEV)以及高端储能系统对锂离子电池的迫切需求,开发具有高比容量、高安全性以及循环寿命长的负极材料成为该领域的主流方向。目前商业化应用的负极材料仍以石墨类碳素材料为主,最大理论比容量只有372 mAh/g,难以满足新一代移动通讯、移动电器以及电动汽车对于锂离子电池容量  相似文献   

10.
硅基材料作为锂离子电池负极具有容量高、来源广泛以及环境友好等优势,有望替代目前应用广泛的石墨负极成为下一代锂离子电池的主要负极材料。硅和碳复合构成的锂离子电池复合负极,不但解决了充放电过程中硅体积效应大和碳容量低的问题,而且综合了碳循环性好和硅容量高的特点。从材料选择、结构设计以及电极优化方面简要介绍了硅/碳复合材料的最新研究进展,并对硅碳复合负极未来发展方向进行了展望。  相似文献   

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Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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14.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

18.
Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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