کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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6472753 | 1424136 | 2016 | 8 صفحه PDF | دانلود رایگان |
Lithium difluorophosphate (LiPO2F2) was used as an electrolyte additive to promote the low temperature performance of LiNi0.5Co0.2Mn0.3O2/graphite cells. The impact of LiPO2F2 on the solid electrolyte interface (SEI) film-formation on electrodes was demonstrated by various electrochemical methods and microscopy techniques, such as transmission electron microscopy (TEM), scanning electron microscope (SEM) as well as X-ray photoelectron spectroscopy (XPS), in the pouch cells and half cells. The results showed that the cells containing 1% LiPO2F2 performed 71.9% (â20 °C) and 57.93% (â30 °C) of initial capacity, while the cells without LiPO2F2 discharged only 49.41% and 9.6% of initial capacity under the same condition. In addition, the enhancement of cyclic performance at 0 °C was attributed to a conductive and stable SEI film formed on the graphite by the sacrifice of LiPO2F2, which led to a low impedance and richer content of LiF and Li2CO3 in SEI components, as depicted in XPS.
Journal: Electrochimica Acta - Volume 221, 10 December 2016, Pages 107-114