On the characterization of lithium-ion batteries under overtemperature and overcharge conditions: Identification of abuse areas and experimental validation

Although lithium-ion batteries have gained considerable popularity in renewable energy and electric vehicle applications, their safety still remains a concern under certain voltage, temperature, or state of charge conditions. This can lead to degradation and potential thermal runaway. In order to improve the safety assessment of LIBs based on their operating conditions, it is therefore essential to analyze not only their safe operating area but also their abuse region. This study focuses on the characterization of the abuse region of lithium-ion batteries by proposing a new methodology in which four areas of abuse are identified and experimentally validated using a commercial 3.6 Ah pouch cell. The cell is subjected to overtemperature and overcharge conditions, exploring various states of charge (0 to 200%) and ambient temperatures (25 to 100 degrees C). The influence of temperature and state of charge on the battery's behavior is thoroughly analyzed to fully characterize the abuse region. Results reveal the limiting temperatures and states of charge that define the boundaries of the abuse areas. By extending the characterization of LIBs behavior beyond the safe operation area with the determination of four areas of abuse, this article contributes to a better understanding of the phenomena and abuse mechanisms produced by overtemperature and overcharge events with an eye to improving battery safety.