Apparatus and method for inhibiting thermal runaway of battery

Abstract

Disclosed in the present invention are an apparatus and method for inhibiting thermal runaway of a battery. The apparatus comprises pressure relief valves located at the tops of batteries; a detection box is provided above the pressure relief value of each battery; the plurality of detection boxes are communicated with each other; and each detection box is filled with a liquid fire extinguishing agent and an inert gas. A fire extinguishing mechanism of the present invention has a simple structure, and does not need a corresponding electric control mechanism to maintain normal operation of a fire extinguishing apparatus, so that the present invention has low cost and is conducive to application and popularization in the field of energy storage.

Description

Device and method for inhibiting battery thermal runaway TECHNICAL FIELD

[0001] The present application relates to the technical field of thermal runaway inhibition of energy storage tanks, and in particular to a device and method for inhibiting battery thermal runaway. BACKGROUND

[0002] Energy storage is a key supporting technology for energy structure adjustment and power system transformation under the new energy wave. Lithium ion batteries, as new energy batteries, are not only more environmentally friendly but also have superior performance, and are widely used in energy storage power stations. Lithium battery assembly energy storage tank solutions are widely used in new energy power generation access and consumption, realizing distributed power generation and microgrid energy storage, providing reliable power supply and power quality for power system frequency and voltage regulation, and providing reliable power supply and power quality in distribution system upgrading.

[0003] However, lithium ion batteries may experience thermal runaway during storage due to heat accumulation from chemical reactions or external heat sources, which can severely affect the safety performance of the energy storage tank. Lithium battery thermal runaway refers to the rapid temperature rise of a lithium battery during charging or discharging due to abnormal reactions within the battery, resulting in uncontrolled chemical reactions within the battery that generate a large amount of heat and gas, which can cause the battery to explode or catch fire.

[0004] Most current energy storage tanks are equipped with corresponding fire extinguishing devices (or thermal runaway inhibition devices) to address the problem of battery thermal runaway. However, these devices have complex structures and require corresponding electronic control mechanisms to maintain normal operation, which is relatively expensive. Moreover, current fire extinguishing devices can only be activated to release extinguishing agents when the battery thermal runaway in the energy storage tank reaches an advanced stage or flames have already appeared, which is too late to completely suppress the flames and results in poor extinguishing effectiveness. The root cause of this problem is that the current fire extinguishing devices for batteries mainly use fire detection tubes or sensors to detect thermal runaway. The fire detection tube melts its wall when high-temperature flames appear, then releases the extinguishing agent inside. The sensor is also triggered when the temperature or smoke reaches a certain level. These methods are passive and lagging, resulting in low efficiency in inhibiting battery thermal runaway.

[0005] SUMMARY

[0006] The present application aims to overcome the above-mentioned deficiencies and provide a device and method for inhibiting battery thermal runaway to address the problems in the background art.

[0007] To solve the above technical problems, the technical scheme adopted by the present application is: a device for inhibiting thermal runaway of a battery, comprising a pressure relief valve located at the top of the battery, a detection box arranged above the pressure relief valve of each battery, and a plurality of detection boxes being communicated with each other.

[0008] Preferably, the battery is arranged in a box.

[0009] Preferably, the liquid fire extinguishing agent is perfluorohexanone fire extinguishing agent.

[0010] Preferably, the detection box is fixed to the top of the battery through a support lining.

[0011] Preferably, the bottom of the box is further provided with an exhaust hole.

[0012] Preferably, the upper surface of the pressure relief valve of each battery is in contact with the bottom of the detection box, a pressure relief diaphragm is arranged in the pressure relief valve, and the bottom of the detection box is also a pressure relief diaphragm structure.

[0013] Preferably, the two detection boxes on the front and back sides are in contact with each other, and a communication valve is arranged at the contact position, and the two detection boxes on the left and right sides are communicated through a connecting pipe.

[0014] In addition, the present application also discloses a method for inhibiting thermal runaway of a battery, which uses the above-mentioned device for inhibiting thermal runaway of a battery, and comprises the following steps:

[0015] S1, when the battery occurs thermal runaway, the pressure relief valve thereof is automatically opened to timely release the combustible gas generated in the battery, and the bottom of the detection box is broken by the impact;

[0016] S2, when the bottom of the detection box is broken, the liquid fire extinguishing agent in the detection box is sprayed out from the broken position under the gas pressure of the inert gas;

[0017] S3, after the liquid fire extinguishing agent is sprayed out, it directly reaches the surrounding of the battery, so as to reduce the temperature near the battery and prevent heat diffusion;

[0018] S4, the combustible gas of the battery and the fire extinguishing agent vapor are discharged from the exhaust hole at the bottom of the box, so as to prevent the combustible gas from gathering in the box to aggravate the degree of thermal runaway of the battery.

[0019] Further, in the step S2, when the bottom of the detection box is broken, after the liquid fire extinguishing agent in the detection box is sprayed out under the gas pressure of the inert gas, the liquid fire extinguishing agent in other detection boxes and the connecting pipe also flows into the detection box under the gas pressure of the inert gas, and then is sprayed out from the broken position.

[0020] The present application has the following beneficial effects:

[0021] 1. The structure of the device of the present invention is relatively simple, and no corresponding electric control mechanism is required to maintain the normal operation of the fire extinguishing device. Its cost is also relatively low, which is conducive to its application and promotion in the field of energy storage.

[0022] 2. The traditional fire detection tube application process requires the appearance of flame high temperature to melt the tube wall and then release the fire extinguishing agent inside. However, when the battery has thermal runaway, the pressure relief valve will automatically open, causing the bottom of the detection box to be impacted and ruptured. The liquid fire extinguishing agent in the detection box is ejected from the rupture position under the action of the inert gas pressure, thereby reducing the temperature near the battery and preventing heat diffusion. Compared with traditional fire extinguishing methods, the present invention can intervene and suppress thermal runaway at the early stage of occurrence, effectively preventing the degree of thermal runaway from worsening. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIG1 is a schematic diagram of the three-dimensional structure of a device for suppressing battery thermal runaway installed in a box (without the box cover);

[0024] FIG2 is a schematic structural diagram of the connection between multiple detection boxes and connecting pipes in FIG1;

[0025] Figure 3 is a schematic diagram of the structure of one of the batteries in the energy storage box;

[0026] FIG4 is a schematic diagram showing the structure of one of the batteries connected to the detection box and the support lining. DETAILED DESCRIPTION

[0027] The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

[0028] As shown in Figures 1-4, a device for suppressing battery thermal runaway includes a pressure relief valve 2 located on top of a battery 1. A detection box 3 is provided above the pressure relief valve 2 of each battery 1. The multiple detection boxes 3 are interconnected and filled with a liquid fire extinguishing agent and an inert gas.

[0029] Preferably, as shown in FIG3 , the battery 1 is disposed in a box 4 .

[0030] Preferably, the liquid fire extinguishing agent is perfluorohexanone fire extinguishing agent.

[0031] Preferably, as shown in Figure 4, the detection box 4 is fixed to the top of the battery 1 through a support lining 5. The detection box 4 can be stably fixed to the top of the battery 1 through the support lining 5.

[0032] Preferably, an exhaust hole is further provided at the bottom of the box body 4. After such design, the combustible gas and the fire extinguishing agent steam inside the box body 4 can be discharged from the exhaust hole in time, preventing the combustible gas and the fire extinguishing agent steam from gathering in the box body 4.

[0033] Preferably, as shown in Figure 4, the upper surface of the pressure relief valve 2 of each battery 1 contacts the bottom of the detection box 3, a pressure relief diaphragm is installed inside the pressure relief valve 2, and the bottom of the detection box 3 is also a pressure relief diaphragm structure. In this embodiment, the pressure relief valve 2 is a pressure relief diaphragm structure. Once an abnormal reaction occurs inside the battery 1, causing the battery temperature to rise rapidly, resulting in a runaway chemical reaction inside the battery and generating a large amount of heat and gas, the diaphragm structure can be quickly broken through under the action of pressure, thereby enabling timely pressure relief. In addition, the bottom of the detection box 3 contacts the pressure relief valve 2. In this way, when the pressure relief valve 2 is broken, since the bottom of the detection box 3 is also a pressure relief diaphragm structure, it is easy to be broken along with it, effectively avoiding the phenomenon that the bottom of the detection box 3 cannot be broken when the pressure relief valve 2 is broken.

[0034] Preferably, as shown in Figure 2, the two detection boxes 3 on the front and rear sides are in contact with each other, and a connecting valve is provided at the contact position, and the two detection boxes 3 on the left and right sides are connected via a connecting pipe 6. The internal environment of the box body 1 is relatively narrow, and by providing this method of front-to-back contact and communication, and left-to-right communication via the connecting pipe 6, space can be effectively saved. In addition, the connecting valve of the detection box 3 can be a combination of a sleeve and a cannula, that is, a cannula is provided on the front side of the detection box 3 and a sleeve is provided on the back side. This allows for direct insertion and facilitates installation.

[0035] In addition, the present invention also discloses a method for suppressing battery thermal runaway, which uses the above-mentioned device for suppressing battery thermal runaway and includes the following steps:

[0036] S1. When battery 1 experiences thermal runaway, its pressure relief valve 2 automatically opens to release the combustible gas generated inside the battery in a timely manner, and the bottom of the detection box 3 is impacted and ruptures;

[0037] S2. When the bottom of the detection box 3 is broken, the liquid fire extinguishing agent in the detection box 3 is ejected from the broken position under the pressure of the inert gas;

[0038] S3, the liquid fire extinguishing agent is sprayed directly to the vicinity of the battery 1, thereby reducing the temperature near the battery 1 and preventing heat diffusion;

[0039] S4. The combustible gas and fire extinguishing agent vapor of the battery 1 are discharged from the exhaust holes at the bottom of the box 4 to prevent the combustible gas from accumulating in the box 4 and causing the thermal runaway of the battery 1 to worsen.

[0040] Furthermore, in step S2, when the bottom of the detection box 3 ruptures, the liquid fire extinguishing agent in that detection box 3 is ejected under the pressure of the inert gas. At the same time, the liquid fire extinguishing agent in the other detection boxes 3 and the connecting pipe 6 also flows into the detection box 3 under the pressure of the inert gas and is then ejected from the ruptured location. In this step, the interconnecting function of the connecting pipe 6 ensures that a sufficient amount of liquid fire extinguishing agent is ejected to cool the area.

[0041] In the embodiment, when thermal runaway occurs in one of the batteries 1, the pressure relief valve 2 bursts, and the perfluorohexone in the detection box 3 is sprayed out. If a naked fire occurs, the perfluorohexone can extinguish the naked fire. Due to the effect of the connecting pipe, it can be ensured that the extinguishing agent has sufficient amount to extinguish the naked fire. If only high temperature occurs without naked fire, the gasification temperature of the perfluorohexone is low, and the proportion after gasification is much higher than air, so it can ensure that the battery temperature is always at a low level and subsequent naked fire is not easy to occur.

[0042] The above-described embodiments are only preferred technical solutions of the present application, and should not be regarded as a limitation of the present application. The protection scope of the present application should be based on the technical solutions recited in the claims, including equivalent replacement solutions of the technical features recited in the claims. That is, equivalent replacement improvements within this scope are also within the protection scope of the present application.

Claims

1. A device for inhibiting thermal runaway of a battery, comprising a pressure relief valve (2) located at the top of the battery (1), characterized in that: The pressure relief valve (2) of each battery (1) is provided with a detection box (3), and the detection boxes (3) are communicated with each other.

2. The device for suppressing thermal runaway of a battery according to claim 1, characterized in that: The battery (1) is arranged in a box (4).

3. The device of claim 1, wherein: The liquid extinguishing agent is perfluorohexanone extinguishing agent.

4. The device of claim 1, wherein: The detection box (4) is fixed to the top of the battery (1) through a supporting inner liner (5).

5. The device of claim 2, wherein: The bottom of the box (4) is also provided with an exhaust hole.

6. The device of claim 1, wherein: The upper surface of the pressure relief valve (2) of each battery (1) is in contact with the bottom of the detection box (3), the pressure relief valve (2) is internally provided with a pressure relief diaphragm, and the bottom of the detection box (3) is also provided with a pressure relief diaphragm structure.

7. The device of claim 1, wherein: The two detection boxes (3) on the front and back sides are in contact with each other, and the contact position is provided with a communication valve, and the two detection boxes (3) on the left and right sides are communicated through a connecting pipe (6).

8. A method of suppressing thermal runaway of a battery using the device for suppressing thermal runaway of a battery according to any one of claims 1 to 7, characterized by: It comprises the following steps: S1, when the battery (1) is in thermal runaway, the pressure relief valve (2) will automatically open to timely release the combustible gas generated in the battery, and the bottom of the detection box (3) is impacted to be broken; S2, when the bottom of the detection box (3) is broken, the liquid extinguishing agent in the detection box (3) is sprayed from the broken position under the gas pressure of the inert gas; S3, the liquid extinguishing agent directly reaches the surrounding of the battery (1) after being sprayed, thereby reducing the temperature near the battery (1) and preventing heat diffusion; S4, the combustible gas of the battery (1) and the extinguishing agent vapor are discharged from the exhaust hole at the bottom of the box (4), so as to prevent the combustible gas from gathering in the box (4) to cause the thermal runaway degree of the battery (1) to be aggravated.

9. The method of claim 8, wherein: In the step S2, when the bottom of the detection box (3) is broken, the liquid extinguishing agent in the detection box (3) is sprayed under the gas pressure of the inert gas, and then the liquid extinguishing agent in other detection boxes (3) and the connecting pipe (6) also flows into the detection box (3) under the gas pressure of the inert gas, and then is sprayed from the broken position.

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