The Effects Of Internal Pressure Evolution On The Aging Of Commercial Li-Ion Cells

摘要

Over the past decade, the market for rechargeable Lithium-Ion batteries (LIB) has significantly grown to match the demands of consumer and commercial customers. Applications which require large storage capacity, high C charge and discharge rates, and long term cycling are of particular interest. Due to the long calendar and cycle life requirements for these applications, it is necessary to understand the aging process of the batteries and their state of health. Electrochemical impedance spectroscopy (EIS) has become one preferred method for nondestructive evaluation aimed at understanding the fundamental aging processes of LIB. While promising, alternative methods for evaluating in-situ battery aging must also be pursued in order to provide the customer a safe and reliable product. This paper discusses internal LIB gas generation, the changes this causes in the internal cell pressure, and the potential correlation of the bulk cell pressure to the aging of the battery.