Effects of rest time after Li plating on safety behavior—ARC tests with commercial high-energy 18650 Li-ion cells

• DOI: 10.1016/j.electacta.2017.02.036
• Publication Date: 2017-02-07T13:01:35Z
• Authors: Thomas Waldmann; Margret Wohlfahrt...
• Keywords: Plating (geology); Exothermic reaction; Thermal Runaway

During charging at low temperatures, metallic Lithium can be deposited on the surface of graphite anodes Li-ion cells. This Li plating does not only lead to fast capacity fade, it also impair safety behavior. The present study observes effect rest periods between and subsequent accelerated rate calorimetry (ARC) tests. As an example, commercial 3.25 Ah 18650-type cells with NCA cathodes are cycled 0 °C provoke plating. It is found that period 25 ARC tests has a significant influence onset temperature exothermic reactions (TSH), thermal runaway (TTR), maximum temperature, self-heating rate, damage patterns 18650 results discussed in terms chemical intercalation into adjacent particles during period. exponential increase recovery TSH as function time suggests reaction 1st order for relaxation process.