Dissecting anode swelling in commercial lithium-ion batteries
Dissecting anode swelling in commercial lithium-ion batteries
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DOI：
10.1016/j.jpowsour.2012.06.071
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发表时间：
2012-11
影响因子：
9.2
通讯作者：
Ningxin Zhang;Huaqiong Tang
中科院分区：
文献类型：
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作者：
Ningxin Zhang;Huaqiong Tang
采用一种新的方法研究了商用锂离子电池电化学过程中的阳极膨胀。阴极表面部分覆盖有一片糊状物，以阻止充电/放电过程中锂离子从活性材料中的传输，并且阳极膜上的相应部分在不同的电化学过程中没有显示出Li-石墨化合物的形成，这通过XRD分析得到证实。测量了锂化区内和锂化区外阳极厚度的增加，并分别定义为电化学膨胀和物理膨胀。由于锂化过程导致的石墨微观晶格膨胀与介观电化学膨胀同步相关，而物理膨胀则随时间逐渐减小。分析了锂离子嵌入引起的微观应力、导致阳极膨胀的介观应力以及大量循环试验后软包电池的宏观波动之间的关系，并从不同尺度的应力演化角度进行了关联，提出了解决阳极膨胀的建议。
An innovative method is applied to investigate anode swelling during electrochemical processes in commercial lithium-ion batteries. Cathode surface is partially covered with a piece of paste to block the transportation of lithium ion from active material during charging/discharging, and the corresponding part on the anode film shows no formation of Li-graphite compounds during different electrochemical processes, which is confirmed by XRD analysis. The increases of anode thickness within and outside lithiated zone are measured, and defined as electrochemical swelling and physical swelling respectively. The microscopic lattice expansion of graphite due to lithiation process correlates to mesoscopic electrochemical swelling synchronically, while physical swelling tends to decrease steadily with time. The relationship among the microscopic stress due to lithium-ion intercalation, the mesoscopic stress resulting in anode swelling, and the macroscopic rippling of pouch cell after a large number of cycle test, is analyzed and correlated in terms of stress evolution across different scales, and suggestions for solving anode swelling are provided.