Quantification and modeling of mechanical degradation in lithium-ion batteries based on nanoscale imaging.
Quantification and modeling of mechanical degradation in lithium-ion batteries based on nanoscale imaging.
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DOI：
10.1038/s41467-018-04477-1
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发表时间：
2018-06-14
影响因子：
16.6
通讯作者：
Wood V
中科院分区：
文献类型：
--
作者：
Müller S;Pietsch P;Brandt BE;Baade P;De Andrade V;De Carlo F;Wood V
锂离子电池电极中的容量衰减可由其中炭黑-粘合剂网络与活性材料分离的降解机制引起。在这里，我们提出了两种方法来可视化和量化这种分离，并使用实验结果来开发和验证一个模型，该模型考虑了活性颗粒的大小，复合电极的粘弹性参数，活性颗粒和炭黑粘合剂域之间的粘附力，以及固体电解质相间生长速率如何影响分离和容量衰减。使用碳-硅复合电极作为模型系统，我们展示了X射线纳米断层扫描和背散射扫描电子显微镜，具有足够的分辨率和对比度，以分割孔隙空间，活性颗粒和炭黑粘合剂域，并量化分层作为循环次数的函数。验证模型进一步用于讨论如何分离和容量衰减的高容量材料可以通过材料工程最小化。硅是一种很有前途的锂离子电池电极材料;然而，形态变化会缩短电池寿命。在本文中，作者使用基于电子和X射线的成像技术来量化微米和纳米尺度上的此类过程，并提出了缓解电池退化的途径。
Capacity fade in lithium-ion battery electrodes can result from a degradation mechanism in which the carbon black-binder network detaches from the active material. Here we present two approaches to visualize and quantify this detachment and use the experimental results to develop and validate a model that considers how the active particle size, the viscoelastic parameters of the composite electrode, the adhesion between the active particle and the carbon black-binder domain, and the solid electrolyte interphase growth rate impact detachment and capacity fade. Using carbon-silicon composite electrodes as a model system, we demonstrate X-ray nano-tomography and backscatter scanning electron microscopy with sufficient resolution and contrast to segment the pore space, active particles, and carbon black-binder domain and quantify delamination as a function of cycle number. The validated model is further used to discuss how detachment and capacity fade in high-capacity materials can be minimized through materials engineering. Silicon is a promising electrode material for lithium-ion batteries; however, morphological changes shorten battery lifetimes. Here the authors use imaging techniques based on electrons and X-rays to quantify such processes at micro- and nanoscales and suggest routes to mitigate battery degradation.