In situ evaluation of mechanical and electrochemical degradation in silicon negative electrode for lithium-ion secondary batteries
In situ evaluation of mechanical and electrochemical degradation in silicon negative electrode for lithium-ion secondary batteries
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锂离子二次电池硅负极机械和电化学降解的原位评估
DOI：
10.1109/nano.2016.7751563
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Toshiyuki Hashida
中科院分区：
文献类型：
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作者：
Naoki Yoshida;Tadashi Sakamoto;Naoaki Kuwata;Junichi Kawamura;Kazuhisa Sato;Toshiyuki Hashida
硅具有很高的比容量，是一种很有前途的锂离子电池负极材料。不幸的是，硅经历了300~400%的完全锂化体积膨胀和严重的容量衰减，这限制了它在商业电池中的成功应用。在本研究中，我们采用原位声发射和激光显微镜观察的方法来检测硅负极的体积变化。结果表明，硅负极的长期性能取决于其在放电阶段的剥落，而在充电阶段只有第一次锂化导致其分层和剥落。这有力地表明，发射的能量，因此的损伤量，与容量损失有关。研究表明，声发射是实时监测电极力学损伤和电化学降解的有力工具。
Silicon is a promising anode material for lithium-ion battery application due to its high specific capacity. Unfortunately, silicon undergoes a volume expansion of 300~400% full lithiation and suffers from severe capacity fade, which limit its successful application in commercial cells. In this study, we used in situ acoustic emission and laser microscope observation method for detecting the volume change in silicon negative electrodes. It was shown that the long-term performance of the silicon negative electrode was dictated by its spallation during the discharge steps, while only the first lithiation caused its delamination and spoliation in the charge step. This strongly indicates that the energy of emission, and hence the amount of damage, is related to capacity loss. This study demonstrate that AE is a powerful tool to survey the real-time mechanical damage and electrochemical degradation in the electrode.