Simulation of thermal runaway prediction model for nickel-rich Lithium ion batteries

Thermal runaway (TR) is a main problem in batteries safety research. With the energy density continuously improve, safety accidents are common in electric vehicles or energy storage power stations, so it is urgent to enhance its safety. Establishing accurate and reasonable TR prediction model is the key to optimize the safety design of battery. In this paper, study the thermal stability of LiNi
_0.8
Co
_0.1
Mn
_0.1
O
₂
/Silicon-carbon (NCM811/Si-C) battery is the main work. First, the exothermic reaction mechanism of the battery is studied by referring to the differential scanning calorimetry (DSC) test curves. Then the Bi-Gaussian functions is used to conduct peak separation on the mixed multi-peak DSC curves, and the multi-peak DSC curves are transformed into multiple single-peak curves. The reaction kinetic parameters are determined by means of linear fitting and parameter identification. A TR prediction model is established by superimposing the exothermic reaction dynamic equations. The model fits well with the 57 Ah lithium-ion battery accelerated rate calorimetry (ARC) test results, verifying the rationality of the prediction model and the parameter acquisition method.