Method and device for measuring thermal runaway heat release of lithium battery in real time

Abstract

The embodiment of the invention provides a method and device for measuring thermal runaway heat release of a lithium battery in real time, and the method comprises the steps of placing a sample lithium battery in a protection cage of a combustion bomb, and heating the sample lithium battery according to a set heating power; calculating the internal energy increment of the battery according to the temperature rise and mass change of the sample lithium battery; according to the set heating power and heating duration, calculating the heating value of a heater in the bomb; calculating the internal absorption energy of the combustion bomb according to the bomb body surface temperature rise of the combustion bomb; according to the moment bomb body surface observation temperature, the environment temperature and the heating duration of the current combustion bomb, calculating the heat dissipating capacity of convection between the wall surface of the combustion bomb and the environment; calculating the internal energy increment of the gas in the combustion bomb according to the change of the gas pressure value in the combustion bomb; and according to the internal energy increment of the battery, the internal absorption energy of the combustion bomb, the heat dissipating capacity of convection between the wall surface of the combustion bomb and the environment, the internal energy increment of gas in the bomb and the heat productivity of the heater in the bomb, calculating the heat release of the sample lithium battery based on a first law of thermodynamics.

Description

technical field [0001] The invention relates to the technical field of batteries, in particular to a method and device for real-time measuring the thermal runaway heat release of a lithium battery. Background technique [0002] For power lithium batteries, the thermal runaway that occurs under various incentives can be divided into two forms. One is the thermal runaway caused by local overheating of the battery and spreading to other areas to induce the overall thermal runaway of the battery. The other is the battery environment. If the temperature is too high, evenly heating the power lithium battery will induce a complete thermal runaway. Among them, the event scenarios corresponding to local thermal runaway mainly include battery puncture, mechanical extrusion, internal short circuit, thermal runaway of adjacent batteries, and local thermal runaway caused by convection, heat conduction, or flame; the corresponding scenarios of battery overall thermal runaway mainly includ...

AI Technical Summary

Problems solved by technology

At present, the experimental instruments and equipment used for the analysis of combustion accidents of lithium batteries mainly include Accelerating Rate Calorimetry (ARC), adiabatic reaction heat energy meter (Vent Sizing Package2, VSP2), differential scanning calorimeter (Differential Scanning Calorimetry, DSC), cone calorimeter, ISO9705 standard fire test room, etc., although there are many experimental instruments and equipment in the research of power lithium battery fire, the existing equipment has thermal runaway triggering means and the actual power lithium battery. There is a large difference in the ignition process, and the shortcomings of the inability to accurately measure the thermal runaway of the power lithium battery and the heat release and heat release rate during the combustion process. In addition, the adiabatic reaction heat energy detector and differential scanning calorimeter also have the space volume of the sample pool. Minor disadvantages, it is difficult to put the power lithium battery module into the sample cell, and it is even difficult to put the battery cell into the sample cell

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