《自然亚洲材料》：高倍率长寿命LiV₃O₈超长纳米线电极材料

如今电动汽车的快速发展对动力电池的功率密度及循环寿命提出了更高的要求，因此瞄准电动汽车的市场需求，研制能量功率特性俱佳的锂电池电极材料成为该领域的研究热点之一。

武汉理工大学-哈佛大学纳米联合重点实验室的麦立强教授研究团队通过锂离子的拓扑嵌入原理制备了LiV₃O₈超长纳米线电极材料，并实现了其在高倍率条件下的示范性应用。LiV₃O₈是一种被广泛研究的钒氧基锂电池正极材料，它的层状结构使其具有高的能量密度，然而传统方法制备的该材料倍率特性较差，且容量衰减较快。纳米线电极材料具有与电解液接触面积大、锂离子脱嵌距离短、电化学活性高等优点，有利于电极材料的高倍率应用。因此，选用与LiV₃O₈具有类似层状结构的H₂V₃O₈超长纳米线作为前驱体，基于锂离子拓扑嵌入原理，通过低温烧结使锂离子原位嵌入H₂V₃O₈层间的八面体空位，使产物LiV₃O₈基本保持前驱体的超长纳米线形貌。该电极材料在1.5 A/g的电流密度下，首次放电容量为176 mAh/g，400次循环后，容量可保持在160 mAh/g，次容量衰减率仅为0.025%。在2 A/g的电流密度下，首次放电容量为137 mAh/g，600次循环后，电池容量仍可达120 mAh/g，次容量衰减率仅为0.022%。该结果表明，LiV₃O₈超长纳米线电极材料兼具高能量密度及高功率密度特性，且循环稳定性好，具有广泛的应用前景。相关工作发表在最新一期的《亚洲材料》上。

Topotactically synthesized ultralong LiV₃O₈ nanowire cathode materials for high-rate and long-life rechargeable lithium batteries

Li-Qiang Mai and co-workers at Wuhan University of Technology and Harvard University have revealed that efficient rechargeable lithium batteries can be built using ultra-long nanowires as electrodes. With the advent of mobile devices, there has been a growing need for electrical charges to be stored in ever smaller spaces, yet at the same time taken up and released increasingly rapidly — but this trade-off between high-energy densities and high-power densities is not easy to achieve. Although rechargeable lithium batteries already present good stability and storage capacity, they need to be charged and discharged much more rapidly. Lithium vanadium oxide (LiV₃O₈) — which features lithium ions intercalated between vanadium oxide layers — is an efficient cathode material whose rate performance can be altered by tuning its morphology. Mai and colleagues have now shown a facile route to prepare ultra-long, crystalline LiV₃O₈ nanowires that endow batteries with excellent stability over time as well as high-rate performances.

作者：Xu Xu, Yan-Zhu Luo, Li-Qiang Mai*, Yun-Long Zhao, Qin-You An, Lin Xu, Fan Hu, Lei Zhang and Qing-Jie Zhang

期刊名称： NPG Asia Materials

期卷页： 2012-06-22 第4卷 第6期：e20

原文链接：http://www.nature.com/am/journal/v4/n6/full/am201236a.html

DOI: 10.1038/am.2012.36

关键词：Materials research, inorganic materials, electrochemical materials, lithium battery, high-power, high-rate, LiV₃O₈ nanowires, topotactic synthesis

相关链接http://paper.sciencenet.cn/htmlpaper/201271113544851225081.shtm?id=25081

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