Multi-point triggered ternary lithium power battery module thermal runaway simulation and prediction method

Abstract

The invention discloses a multi-point triggered ternary lithium power battery module thermal runaway simulation and prediction method, which comprises the steps of establishing a power battery modulethree-dimensional model, and selecting a thermal runaway multi-point triggering position in a battery module; importing the three-dimensional model of the battery module into finite element software;establishing a battery heat production model for the battery pack according to the thermal abuse model, applying a thermal runaway trigger heat source Q to the selected multi-point trigger position battery, dividing a battery domain into quadrangle as a main free grid, and setting a heat exchange mode between batteries as convection and conduction and thermal runaway simulation to obtain battery module temperature, trigger point, heat source and thermal runaway time data; collecting the number n of different triggering points and the average value t of thermal runaway time caused by thermal runaway triggering of the heat source Q, calculating a relational expression between the time t and the thermal runaway heat source Q and the number n of the triggering points through fitting of a nonlinear least square method, and predicting the thermal runaway time of the battery module; and calculating the overall thermal runaway prediction relational expression of the battery module, and calculating the overall thermal runaway time of the module.

Description

technical field [0001] The invention relates to the technical field of electric vehicle power batteries, in particular to a method for simulating and predicting thermal runaway of a ternary lithium power battery module based on multi-point triggering. Background technique [0002] As the core component of electric vehicles, the safety of power batteries has an important influence on the development of electric vehicles. The power battery is prone to thermal runaway under mechanical abuse, electrical abuse and thermal abuse, which will cause serious harm to electric vehicles and personnel safety. Thermal runaway, that is, thermal abuse is the root cause of thermal runaway in power batteries. As an important component of the power battery system, the power battery module is of great significance to the research on its safety. Therefore, a simulation of the thermal runaway of the power battery module caused by multi-point triggering under different collision conditions is need...

AI Technical Summary

Problems solved by technology

The literature studies the thermal runaway time of ternary lithium square power battery cells under different heating furnace temperatures and different heat dissipation conditions, but the objects considered are limited to battery cells, and the trigger mode of thermal runaway of battery cells is environmental High temperature heating means that the battery cells are evenly heated. However, in practical applications, the heating positions of the batteries are mostly uneven, and in electric vehicles, the cells are used as the basic unit of the battery system in groups. Therefore, only the power battery cells Conducting thermal runaway research does not give a good grasp of the law of thermal runaway of power batteries in actual use

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