A method for improving temperature applicability and accuracy modeling of electrochemical-thermal coupling model

Abstract

The invention discloses a method for improving the temperature applicability and accuracy modeling of an electrochemical-thermal coupling model, comprising the steps of testing and measuring an entropy thermal coefficient, wherein the entropy thermal coefficient of a battery is closely related to the heat production of the battery; establishing a lithium ion battery electrochemical model accordingto the measured entropy thermal coefficient and the electrochemical modeling control equation; establishing the electrochemical-thermal coupling model of a lithium ion battery by combining the lithium ion battery electrochemical model with the thermal characteristic equation of the lithium ion battery; establishing the correction functions S (T) and H (T) of the solid diffusion coefficient and reference reaction rate with temperature; introducing the correction functions into the electrochemical-thermal coupling model of the lithium ion battery; adding the tested and measured entropy thermalcoefficient in the electrochemical-thermal coupling model to the accuracy of the electrochemical-thermal coupling model along with the temperature change of the battery. By carrying out the temperature correction factor adjustment on the two parameters of the solid diffusion coefficient and the reference reaction rate constant, the electrochemical-thermal coupling model can be used for battery electrochemistry-thermal characteristic research at different temperatures and operating conditions, thereby improving the temperature adaptability of the model.

Description

Technical field [0001] The invention belongs to the field of electric vehicles, and particularly relates to a modeling method for improving the temperature applicability and accuracy of an electrochemical-thermal coupling model. Background technique [0002] The performance of electric vehicles requires that the power battery used as the power source has the characteristics of high specific energy and specific power. In the process of the extreme pursuit of high specific energy of power batteries, there are often reports of electric vehicle power batteries catching fire or even exploding. These fire and explosion factors are mostly caused by thermal runaway during use. Therefore, the safety of batteries has become one of the main reasons restricting the development of electric vehicles. During use of the battery, due to changes in the use conditions or external environment, the heat accumulated inside the battery will increase rapidly, thereby affecting the safety performance of...

AI Technical Summary

Problems solved by technology

During the use of the battery, due to changes in the use conditions or the external environment, the heat accumulated inside the battery will increase rapidly, thus affecting the safety performance of the battery

For example, under the condition of internal short circuit, collision or high temperature, if the heat dissipation is not timely, it will cause the internal temperature of the battery to accumulate. When it reaches a certain temperature, a series of side reactions will occur, causing the temperature to rise sharply, causing safety hazards during use.

When the temperature of the battery is relatively high, it will not only cause safety hazards, but also reduce battery performance and service life

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