In-operando deformation studies on the mechano-electrochemical mechanism in free-standing MWCNTs/V2O5 lithium ion battery electrode
In-operando deformation studies on the mechano-electrochemical mechanism in free-standing MWCNTs/V2O5 lithium ion battery electrode
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自支撑MWCNTs/V2O5锂离子电池电极的机械电化学机理的操作中变形研究
DOI：
10.1016/j.electacta.2019.03.039
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发表时间：
2019
影响因子：
6.6
通讯作者：
Fang Daining
中科院分区：
文献类型：
--
作者：
Wang Zhuo;Huang Huiyu;Zeng Li;Wang Yuncheng;Lv Liang;Dai Cuiying;Mao Weiguo;Chen Xi;Fang Daining
采用水热法、静电自组装法和真空过滤沉积技术制备了MWCNTs/V2 O 5纳米带自支撑结构锂离子电池电极。这种纳米结构增强了V2 O 5阴极的电化学动力学和结构稳定性。采用数字图像相关法对自支撑MWCNTs/V2 O 5阴极表面平面应变的分布和演化特征进行了实时监测，并对其进行了系统的讨论。应变结果表明，恒电流充放电循环下，应变随电位的变化服从一般的阿耳忒弥斯关系。考虑到锂离子浓度的影响，采用纳米压痕法确定了20wt%MWCNTs/V2 O 5电极的弹性模量。通过力学-电化学本构方程，分析了自支撑MWCNTs/V2 O 5电极在电化学过程中平均平面应力的变化规律，以及力学和电化学组分的贡献。本文所采用的分析方法对于揭示LIB中电极的机械-电化学失效机理具有普遍意义。
Free-standing MWCNTs/V2O5nanobelts composite architecture electrodes for lithium ion batteries (LIBs) are prepared based on hydrothermal method, electrostatic self-assembly approach and vacuum filtration deposition technique. Such kind of nanoarchitecture enhances the electrochemical kinetics and structural stability of V2O5cathodes. The distribution and evolution features of plane strains in free-standing MWCNTs/V2O5cathodes surface are in-operando monitored by using digital image correlation method and systematically discussed. The strain results show that the evolution of strain against potential obeys general Arrhenius relation under galvanostatic charge-discharge cycling. Considering the effect of lithium ion concentration, the elastic modulus of 20 wt% MWCNTs/V2O5electrode is confirmed via nanoindentation. The evolutions of average plane stresses in the free-standing MWCNTs/V2O5electrodes, as well as the contributions of mechanical and electrochemical components, are evaluated and discussed by mechano-electrochemical constitutive equation during electrochemical process. The analytical methods used in this article are universal for revealing the electrode mechano-electrochemical failure mechanism in LIBs.