Asymmetry between charge and discharge during high rate cycling in LiFePO4 – In Situ X-ray diffraction study
Asymmetry between charge and discharge during high rate cycling in LiFePO4 – In Situ X-ray diffraction study
复制标题
DOI：
10.1016/j.elecom.2008.02.002
复制
发表时间：
2008-04
影响因子：
5.4
通讯作者：
H. Shin;K. Chung;W. Min;D. Byun;H. Jang;B. Cho
中科院分区：
文献类型：
--
作者：
H. Shin;K. Chung;W. Min;D. Byun;H. Jang;B. Cho
利用同步加速器原位XRD研究了c包覆lifepo4充放电过程中结构变化的不对称行为。c包覆lifepo4在充电过程中由三叶石转变为异质，在放电过程中由三叶石转变为异质。然而，c包覆的Li1−xfepo4在放电过程中的相变比在充电过程中的相变更难完全。在2C速率下，放电过程中几乎没有观察到从异质到三叶石的相变，而在之前的充电过程中观察到完全的相变。这表明相变的完全程度取决于相变的方向。
Asymmetric behavior of structural changes during charge and discharge of C-coated LiFePO4has been investigated using synchrotron based in situ XRD. C-coated LiFePO4undergoes phase transformation from triphylite to heterosite during charge and vise versa during discharge. However, it is observed that the phase transformation of C-coated Li1−xFePO4during discharge is more difficult to be complete than that during charge. At 2C rate, the phase transformation from heterosite to triphylite was hardly observed during discharge while the complete phase transformation was observed in the previous charge. This indicates that the degree of the phase transformation completeness depends on the direction of the phase transformations.