期刊
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
卷 166, 期 6, 页码 A996-A1003出版社
ELECTROCHEMICAL SOC INC
DOI: 10.1149/2.0401906jes
关键词
-
资金
- U.S. DOE's Office of Vehicle Technologies
- Applied Battery Research (ABR) for Transportation Program
- [DE-AC02-06CH11357]
Increasing the charge rate of Li-ion cells over 1-2C (full charge in 30-60 min) would be highly desirable, but high currents flowing through the active materials push these cells to their endurance limits. In this article, we aim to understand how such high-current regimes affect electrochemical properties of the cells. Formation of Li metal deposits is a recognized hazard of high-rate charging, as Li plating can overtake lithium intercalation in the negative electrode. Here we demonstrate how microprobe Li/Cu reference electrodes can be used to characterize the graphite anode and layered oxide (NCM523) cathode during constant-current (<= 6C) voltage-limited (4.39 V) charging of Li-ion cells. These reference electrodes are used to monitor the onset of Li plating conditions in situ during cell charging. As the current increases over 3C, the anode potentials decrease below -40 mV causing lithium nucleation. Surprisingly, this nucleation (at least, initially) does not result in capacity fade or a higher anode impedance even in strongly polarized cells, so it appears that the nascent Li nuclei are isolated from electrolyte by the pre-existing solid electrolyte interphase. Our study shows that microprobe reference electrodes are an important diagnostic tool to characterize full-cell behavior in the high-current regimes. (C) The Author(s) 2019. Published by ECS.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据