The Effect of Amine Additives on the Thermal Runaway Inhibition of SiC ||NCM811 Batteries

Bo-wen Hou, State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China;
Long He, Department of Automotive Engineering, School of Mechanical Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China;
Xu-ning Feng, State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China;
Wei-feng Zhang, State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China;
Li Wang, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China;
Xiang-ming He, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China;

Abstract

The high energy density of the NCM batteries with high nickel content is a key advantage in replacing fossil fuels and promoting clean energy development, but also a fundamental cause of serious safety hazards in batteries. Primary and secondary amines can lead to ring-opening polymerization of common ethylene carbonate electrolytes, resulting in an isolation layer between the cathode and the anode, and improving the thermal safety of the battery. In this work, the safety of batteries is considered at the material level and at the cell level, based on the chemical reactions between amines and the battery components. At the material level, the effect of the presence or absence of amine additives on the thermal stability of the different components of the lithium-ion battery is tested by DSC. At the cell level, the safety of the whole battery with and without additives was tested by using ARC to extract thermal runaway (TR) characteristic temperatures. The addition of the amine resulted in an earlier onset of some of the chemical reactions between the battery components, as well as a significant reduction in total heat release and a decrease in the maximum temperature rise rate, such that TR was effectively suppressed.