Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5149615 | Journal of Power Sources | 2017 | 7 Pages |
Abstract
In this study, commercial Li(Ni1/3Co1/3Mn1/3)O2/graphite (NCM/C) lithium-ion batteries were cycled at â10 °C under different current rates ranging from 0.2 C to 1C. Electrochemical measurements and post-mortem analysis were performed to identify the root causes of the degradation in the electrochemical performance of the cells. The results reveal that apart from the increase of lithium plating on the anode, there is a considerable and abnormal capacity loss on the NCM cathode with the increase in current rate. The different degradation mechanisms including the loss of lithium inventory (LLI) and the specific capacity loss of NCM material (LAM) during cycling at â10 °C were analyzed quantitatively. It is shown that the evolution trend of LLI with the increase in current rate (8.6%, 35.0%, 55.8% for 0.2 C, 0.5 C and 1 C respectively) corresponds closely to that of the capacity loss of the full-cells (8.6%, 45.5%, 63.6% for 0.2 C, 0.5 C and 1 C, respectively), which is different to the trend of LAM (7.2%, 8.8%, 22.3% for 0.2 C, 0.5 C and 1 C, respectively). Further analysis by XRD and HR-TEM clearly indicates that the crystallinity of the hexagonal layered structure of NCM was greatly impaired after low-temperature cycling at â10 °C, and spinel phase can be observed among the layered structure.
Related Topics
Physical Sciences and Engineering
Chemistry
Electrochemistry
Authors
Yiyang Li, Kun Qian, Yan-Bing He, Yusuf Valentino Kaneti, Dongqing Liu, Dan Luo, Hai Li, Baohua Li, Feiyu Kang,