Influence of electrode processing and electrolyte composition on multiwall carbon nanotube negative electrodes for sodium ion batteries
Influence of electrode processing and electrolyte composition on multiwall carbon nanotube negative electrodes for sodium ion batteries
复制标题
电极处理和电解液成分对钠离子电池多壁碳纳米管负极的影响
DOI：
10.1088/2515-7655/acb3fc
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发表时间：
2023
期刊：
影响因子：
9
通讯作者：
Fuente Cuesta A
中科院分区：
文献类型：
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作者：
Fuente Cuesta A
纳米结构的一维多壁碳纳米管具有多种有利的性质，包括良好的导电性和机械强度，因此已被广泛研究用于锂离子电池电极中作为导电和微结构添加剂，尽管它们也具有一些电化学活性。它们在钠离子电池中的应用研究较少，因此需要更好地了解与钠的电化学反应以及浆料成分和电解质配方的影响，特别是因为这些可能是未来钠离子电极配方中的成分。在这里，我们报告的制造水和有机多壁碳纳米管（MWCNT）负电极球磨处理。注意到所选择的粘合剂极大地影响电化学性能，在25至500 mA g-1的电流密度范围内的容量保持率和倍率性能。从碳酸盐基电解质切换到二甘醇二甲醚基电解质显著提高了初始库仑效率（约10%-60%），这归因于较少的固体电解质界面的形成，并且能够实现可逆机制，根据所使用的粘合剂，在100次循环中容量高达150 mAh g− 1。通过粉末X射线衍射、透射电子显微镜和拉曼光谱对放电和循环的碳纳米管进行非原位表征，提供了对多壁碳纳米管如何进行钠化的深入了解，并证明了当使用基于二甘醇二甲醚的电解质时，在循环期间部分可逆的结构转变。这项工作为更好地理解这些多功能材料奠定了基础，特别是当用于最有前途的锂离子替代储能技术时。
Nanostructured one-dimensional multiwall-carbon nanotubes have a variety of advantageous properties including good electrical conductivity and mechanical strength, and thus have been widely investigated for use in lithium-ion battery electrodes as conductive and microstructural additives, though they also possess some electrochemical activity. Their application to sodium-ion batteries has been less extensively researched, and therefore a greater understanding of the electrochemical reaction with sodium, and effects of slurry composition and electrolyte formulation is warranted, especially as these are likely components in future Na-ion electrode formulations. Here, we report the fabrication of aqueous and organic multi-wall carbon nanotube (MWCNT) negative electrodes processed by ball milling. The binder of choice is noted to greatly affect the electrochemical performance, both in terms of capacity retention and rate capability over a range of current densities from 25 to 500 mA g− 1. Switching from a carbonate-to diglyme-based electrolyte considerably improves initial coulombic efficiencies (∼ 10%–60%), attributed to less extensive formation of solid electrolyte interphase, and enables a reversible mechanism with capacities up to 150 mAh g− 1 over 100 cycles depending upon the binder used. Ex-situ characterization of the discharged and cycled carbon nanotubes by powder x-ray diffraction, transmission electron microscopy and Raman spectroscopy provide an insight into how MWCNTs undergo sodiation and demonstrate a partially reversible structural transformation during cycling when using the diglyme-based electrolyte. This work lays the foundation for a better understanding of these versatile materials, especially when used in the most promising alternative energy storage technology to lithium ion.