Thermal runaway features of large format prismatic lithium ion battery using extended volume accelerating rate calorimetry

详细信息    查看全文

• 作者：Xuning Feng ; Mou Fang ; Xiangming He ; Minggao Ouyang ; Languang Lu ; Hao Wang ; Mingxuan Zhang
• 关键词：Lithium ion battery ; Thermal runaway ; Large format ; Extended volume accelerating rate calorimetry
• 刊名：Journal of Power Sources
• 出版年：1 June, 2014
• 年：2014
• 卷：255
• 期：Complete
• 页码：294-301
• 全文大小：2629 K

文摘

In this paper, the thermal runaway features of a 25聽Ah large format prismatic lithium ion battery with Li(Ni_xCo_yMn_z)O₂ (NCM) cathode are evaluated using the extended volume-accelerating rate calorimetry (EV-ARC). 4 thermocouples are set at different positions of the battery. The temperature inside the battery is 870聽掳C or so, much higher than that outside the battery. The temperature difference is calculated from the recorded data. The temperature difference within the battery stays lower than 1聽掳C for 97% of the test period, while it rises to its highest, approximately 520聽掳C, when thermal runaway happens. The voltage of the battery is also measured during the test. It takes 15-40聽s from the sharp drop of voltage to the instantaneous rise of temperature. Such a time interval is beneficial for early warning of the thermal runaway. Using a pulse charge/discharge profile, the internal resistance is derived from the quotient of the pulse voltage and the current during the ARC test. The internal resistance of the battery increases slowly from 20聽m惟 to 60聽m惟 before thermal runaway, while it rises to 370聽m惟 when thermal runaway happens indicating the loss of the integrity of the separator or the battery swell.