Technical Paper
Low-Temperature Aging Effect on Safety of Lithium-Ion Batteries Subjected to Intrusion: A Comparative Study of 18650 and Pouch Cells
2024-04-09
2024-01-2063
This study investigates the impact of cycling aging on the safety performance of lithium-ion batteries, specifically 18650 cells and pouch cells. These cells are cycled at 0 °C with charging rates of 2 C and 0.8 C, respectively, upon reaching different states-of-health, and their mechanical-electrical-thermal responses are analyzed post-indentation tests. The compressive behavior of anodes and cathodes at different states-of-health is also examined. The failure mechanisms of battery components are discussed based on indentation results at cell level, compression results of components, electrochemical impedance spectroscopy, and visual observations. The study reveals that aged 18650 cells exhibit increased stiffness (evidenced by left-shifted force-displacement curves) during cell indentation, while the compressions test results of aged electrodes show decreased stiffness (right-shifted force-displacement curves) which is similar to the stiffness behavior of the pouch cells.