Investigating the critical characteristics of thermal runaway process for LiFePO4/graphite batteries by a ceased segmented method

Xuan Tang; Guangxu Zhang; Xueyuan Wang; Gang Wei; Guangshuai Han; Jiangong Zhu; Xuezhe Wei; Haifeng Dai

doi:10.1016/j.isci.2021.103088

Investigating the critical characteristics of thermal runaway process for LiFePO₄/graphite batteries by a ceased segmented method

iScience. 2021 Sep 4;24(10):103088. doi: 10.1016/j.isci.2021.103088. eCollection 2021 Oct 22.

Authors

Xuan Tang^{1

2}, Guangxu Zhang^{1

2}, Xueyuan Wang^{1

2}, Gang Wei^{1

2}, Guangshuai Han^{3

4}, Jiangong Zhu^{1

5}, Xuezhe Wei^{1

2}, Haifeng Dai^{1

2}

Affiliations

¹ Clean Energy Automotive Engineering Center, Tongji University, Shanghai 201804, China.
² School of Automotive Studies, Tongji University, Shanghai 201804, China.
³ Institute for Advanced Study, Tongji University, Shanghai 200092, China.
⁴ Shanghai AI NEV Innovative Platform Co., Ltd., Shanghai 201804, China.
⁵ Institute for Applied Materials (IAM), Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen 76344, Germany.

Abstract

Lithium-ion batteries (LIBs) are widely used as the energy carrier in our daily life. However, the higher energy density of LIBs results in poor safety performance. Thermal runaway (TR) is the critical problem which hinders the further application of LIBs. Clarifying the mechanism of TR evolution is beneficial to safer cell design and safety management. In this paper, liquid nitrogen spray is proved to be an effective way to stop the violent reaction of LIBs during the TR process. Based on extended-volume accelerating rate calorimetry, the liquid nitrogen ceasing combined with non-atmospheric exposure analysis is used to investigate the TR evolution about LiFePO₄/graphite batteries at critical temperature. Specifically, the geometrical shape, voltage, and impedance change are monitored during the TR process on the cell level. The morphologies/constitution of electrodes and separators are presented on the component level. Utilizing the gas analysis, the failure mechanism of the prismatic LiFePO₄/graphite battery is studied comprehensively.

Keywords: Electrochemistry; Energy application; Energy storage.