Thermal management module for square battery, and preparation method thereof, and battery pack

Abstract

The invention relates to a thermal management module for a square battery, and a preparation method thereof, and a battery pack. The thermal management module comprises a thermal management material molding body, which is prepared from a thermal management material through a molding method, wherein the thermal management material contains, by mass, 55-90% of a phase change material, 4-20% of a thermal conduction filler, 4-20% of a flame retardant, and 2-10% of chopped fiber. According to the present invention, by adding the chopped fiber, the thermal management module can provide the effectiveenhancing effect, and can greatly increase the phase change material content in the thermal management material so as to improve the heat storage capacity of the thermal management module and stablyregulate and control the temperature.

Description

technical field [0001] The invention relates to the technical field of battery heat management, in particular to a heat management module for a prismatic battery, a preparation method thereof, and a battery pack. Background technique [0002] Batteries such as secondary batteries have been widely used as energy sources for wireless mobile devices, such as power sources for electric vehicles, hybrid electric vehicles, and plug-in hybrid electric vehicles, etc., thereby solving problems caused by vehicles using petroleum fuels. issues such as air pollution. Small wireless mobile devices may use one or more battery cells, while medium or large wireless devices such as vehicles may use medium or large battery modules that include multiple battery cells that are electrically connected to each other. Such medium or large battery modules typically A prismatic battery manufactured to have as small a size and weight as possible so as to be stackable with a high degree of integration...

AI Technical Summary

Problems solved by technology

The solution of the air-cooled thermal management device is also relatively simple, and more consideration is given to the heat dissipation of the battery, but there is a blank in the preheating function of the battery when it is cold started.

Moreover, the prior art has the following problems: (1) the way of forced convection cooling, because no ventilation duct is designed, the effect of cooling and cooling the power battery close to the electronic fan is more significant, but it will be difficult to effectively cool the power battery far away from the electronic fan. Cool down and dissipate heat, which will lead to uneven internal temperature of each battery cell inside the battery box, and the natural convection cooling method cannot efficiently dissipate heat for the power battery; (2) There is no pre-heating function, after the battery is forced to cold start, It will have a serious impact on the service life of the power battery; (3) The air volume entering the battery modules is quite different, and the heat generation and heat dissipation environments of each module are different, resulting in each battery module working at different ambient temperatures, so that the modules The temperature difference between the modules will increase sharply. This temperature difference between modules will cause inconsistency in battery performance, which will eventually affect the performance and life of the entire battery module.

However, the material composition used in the diaphragm is relatively single, and the phase change material is prone to seep out after the phase change material is melted and transformed.

[0009] Therefore, although there are phase change materials used in the prior art for battery thermal management solutions, these battery thermal management materials have low thermal conductivity and poor thermal conductivity, which are likely to cause the following problems:

[0010] 1) When a single battery is overheated, the heat cannot be effectively removed, and it is easy to cause uneven temperature among the single batteries in the battery pack;

[0011] 2) When the temperature of the battery pack continues to rise, it will also cause the temperature of the entire battery pack to exceed the tolerance temperature, which will accelerate the deterioration of the battery module, thereby reducing the service life, and some battery packs may even catch fire or explode, bringing greater safety Hidden danger;

[0012] 3) If the battery pack works at high temperature for a long time, the output power of the battery pack will drop significantly with the increase of temperature, so that the battery pack cannot fully exert its maximum performance

[0013] In addition, these thermal management materials also have problems such as poor flame retardancy, easy combustion, poor shape stability and cycle stability of the components made, and easy leakage on the surface of the components.

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