Anti-overheating, anti-spontaneous combustion and anti-spontaneous explosion method for battery pack

Abstract

The invention relates to the technical field of battery pack safety and heat dissipation, and discloses an anti-overheating, anti-spontaneous combustion and anti-spontaneous explosion method for a battery pack, which comprises a box body, a cooling unit and a decompression unit. The battery pack is composed of an inner shell, an outer shell, a battery pack module, a stand column plate module, a battery grid, a battery pack grid, a flow dividing hole pipe and a flow guiding liquid pipe. A liquid inlet is formed in one side of the battery pack, a liquid pumping opening is formed in the other side of the battery pack, a liquid inlet and a liquid outlet are formed outside the battery pack, and spaces are formed around the batteries for direct heat dissipation. The cooling unit comprises a temperature controller, a cooling liquid pump and an electric valve. The decompression unit comprises an external heat exchanger, a vacuum pump and an exhaust safety valve. The anti-overheating, anti-spontaneous combustion and anti-spontaneous explosion method for the battery pack disclosed in the invention has the characteristics of low cost, high efficiency, simple structure and strong universality,and a method of directly soaking a battery without closing or enclosing frame liquid.

Description

technical field [0001] The invention belongs to the technical field of battery packs, and in particular relates to a method for preventing overheating, spontaneous combustion, and self-explosion of a battery pack. Background technique [0002] At present, electric vehicle power battery spontaneous combustion incidents occur frequently. With the rapid development of new energy vehicles, the safety of new energy vehicles has become the primary problem to be solved. However, the existing battery pack heat dissipation technology and battery management system (BMS ), neither can completely solve the problem of spontaneous combustion and self-explosion of battery packs, because there are many shortcomings and functional limitations, as follows: [0003] Disadvantages of the existing air-cooled heat exchange technology: air-cooled heat dissipation is the lowest efficiency, which will reduce the service life of lithium batteries, and for battery packs, not only will it generate dust...

AI Technical Summary

Problems solved by technology

[0002] At present, electric vehicle power battery spontaneous combustion incidents occur frequently. With the rapid development of new energy vehicles, the safety of new energy vehicles has become the primary problem to be solved. However, the existing battery pack heat dissipation technology and battery management system (BMS ), neither can completely solve the problem of spontaneous combustion and self-explosion of battery packs, because there are many shortcomings and functional limitations, as follows:

[0003] Disadvantages of the existing air-cooled heat exchange technology: air-cooled heat dissipation is the lowest efficiency, which will reduce the service life of lithium batteries, and for battery packs, not only will it generate dust, but air-cooled is even more unsafe because it will The oxygen is directly delivered to the battery pack. Once an internal short circuit spontaneously ignites and self-explodes in individual batteries, the air cooling will bring or have sufficient oxygen, which will immediately cause a violent reaction, which may further trigger the self-ignition and self-explosion of the entire battery pack.

[0004] Disadvantages of the existing liquid cooling heat dissipation technology: When the electric vehicle is stationary and completely cut off, when the management system fails, the heat dissipation system cannot be activated in time, and the heat generated when the electrolyte leaks and the oxidation reaction occurs, will be caused by the surrounding battery. Besieged by isolation materials, heat-conducting materials, flow-guiding media, "cooling channels", etc., or closed by multiple battery cell stacks, local overheating, heat trapping, and heat resistance will occur, leaving further damage to the battery pack. Overall spontaneous combustion and self-explosion hazard

[0005] The limitations of the battery management system (BMS): The current reality of frequent spontaneous combustion and self-explosion accidents in electric vehicles has proved that no matter how good the battery management system (BMS) is, it cannot solve the problems inside the battery, such as battery fast charging and overcharging It has caused the positive electrode to release oxygen and the negative electrode to precipitate lithium, instantaneous chemical reaction, instantaneous short circuit in the battery, electrolyte oxidation and combustion, electrolyte leakage and crystal accumulation, etc., which further caused the thermal runaway of the battery pack, which is not external. The reason is that it is not possible to stop the reaction by cutting off the overcharge and overdischarge power supply in time. The BMS management system is powerless, especially when the power is completely cut off when the battery management system is turned off or fails when it is parked and stationary. It will happen; not only that, the chemical reaction of the electrolyte, the humid air or the electrolysis of water will produce hydrogen. During operation or impact, vibration, friction and extrusion may cause various arc sparks, which will cause the existing hydrogen to spontaneously ignite and explode. These are not controlled by the battery management system (BMS). This is the root cause of frequent spontaneous combustion and self-explosion in car companies with the best BMS technology.

[0006] It can be seen that all the above factors that may cause spontaneous combustion and self-explosion of lithium batteries cannot be solved by the battery management system (BMS) and the existing heat dissipation technology, so new technologies are needed to fundamentally solve the problem of battery packs. The problem of overall spontaneous combustion and self-explosion

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