Self-venting heat pipe for battery

Abstract

The application discloses a self-explosion heat pipe for a battery, comprising a heat pipe body with a hollow structure, characterized in that a fire-fighting heat-conducting medium is stored in the hollow structure of the heat pipe body; a self-explosion device is arranged in the heat pipe body; when the temperature of the heat pipe reaches a threshold value, the self-explosion device in the heat pipe body is started, the generated pressure makes the weak part of the heat pipe body explode, and the fire-fighting heat-conducting medium is released, so that the fire in the battery or the battery box is prevented or extinguished.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a self-venting heat pipe for batteries. Background Technology

[0002] In recent years, lithium battery technology has developed rapidly and has been applied to more and more fields. However, due to the principle and structural characteristics of lithium batteries, they often generate significant heat due to internal resistance during repeated use, and this heat gradually increases. If the accumulated heat cannot be effectively dissipated, it will affect the stability of battery use and shorten the lifespan of the lithium battery. If the temperature rises further, the electrolyte and solvent inside will decompose, burn, or explode.

[0003] Currently, the main method for dealing with fires caused by battery thermal runaway is traditional fire extinguishing agents. However, this method can only extinguish the fire source outside the battery and cannot extinguish the fire from the inside. If the thermal runaway inside the battery continues, it will lead to a secondary reignition of the battery.

[0004] A heat pipe is a superconductor, typically composed of a core, an internal wick, and a heat-conducting medium. Its thermal conductivity exceeds that of any known metal. Its working principle is as follows: when one end of the heat pipe is heated, the heat-conducting medium evaporates and vaporizes. The vapor flows to the other end under a small pressure difference, releasing heat and condensing into a liquid. The liquid then flows back to the evaporation section along the porous material due to gravity or capillary action. This cycle repeats, transferring heat from one end of the heat pipe to the other, thus achieving heat conduction. Currently, heat pipes on the market only have heat conduction capabilities; none are found to also function as fire suppression systems.

[0005] Patent CN111912268A discloses a heat pipe with heat conduction and fire suppression functions. The bottom of the heat pipe is connected to a container that stores a heat-conducting fire suppression medium. A release pipe assembly with a valve is installed on the container. This structure allows for heat conduction at room temperature. When a battery pack malfunctions and overheats, the medium in the container is sprayed into the battery pack to achieve cooling and fire suppression.

[0006] Patent CN212914289U discloses a battery pack heat pipe device with fire extinguishing and heat conduction functions, including a hollow heat pipe body and a container at the bottom of the heat pipe body. The top of the heat pipe body is provided with a cap, and the inner wall of the heat pipe body is provided with a liquid-absorbing core, which forms a hollow space. The container stores a medium, and the inner cavity of the container is connected to the hollow space inside the heat pipe body. The heat pipe is also provided with a release pipe assembly, which is equipped with a valve and is connected to the heat pipe body or the container. When the air pressure in the container reaches a preset value, the valve opens, and the medium is sprayed out through the release pipe assembly.

[0007] In the above patents, the container contains a fire-fighting medium. When the temperature and pressure reach a certain threshold, the release pipe assembly releases the fire-fighting substance to achieve the fire-fighting function. However, both of the above solutions require a separate medium storage container, which is complex in structure and not suitable for practical use. Summary of the Invention

[0008] To solve the above-mentioned technical problems, the technical solution adopted in this application is as follows:

[0009] This application provides a self-venting heat pipe for batteries, including a heat pipe body with a hollow structure, characterized in that the hollow structure of the heat pipe body stores a fire-fighting heat-conducting medium.

[0010] The heat pipe body is equipped with a self-destruct device;

[0011] When the heat pipe temperature reaches the threshold, the self-destruct device inside the heat pipe body is activated, and the resulting pressure causes the weak part of the heat pipe body to burst open, releasing the fire-fighting heat conduction medium.

[0012] Furthermore, the self-destruct device stores a heat-sensitive self-ignition agent that can be activated within a specific temperature threshold.

[0013] Furthermore, the self-starting temperature threshold range of the temperature-sensitive self-ignition agent is 150℃~200℃.

[0014] Furthermore, the self-destruct device also contains a gas-generating agent. The temperature-sensitive self-ignition agent is activated at a certain temperature threshold, further igniting the gas-generating agent and producing a large amount of gas. This causes the gas pressure inside the heat pipe to rise rapidly, thereby causing the weakest part of the heat pipe body to burst open and release the fire-fighting heat-conducting medium.

[0015] Furthermore, the explosive agent inside the self-destruct device is sealed and stored in a metal casing that is compatible with the fire-fighting heat-conducting medium.

[0016] It is understood that the casing of the self-destruct device can also be a non-metallic casing compatible with the fire-fighting heat-conducting medium.

[0017] More preferably, the metal casing is a copper casing or an aluminum casing.

[0018] Furthermore, the fire-fighting heat-conducting medium is perfluoroketone, pentafluoroethane, difluoromethane, difluorochlorobromomethane, trifluorobromomethane, tetrafluorodibromoethane, heptafluoropropane, trifluoromethane, difluorobromomethane, chlorobromomethane, difluorodibromomethane, trimethyl phosphate, triethyl phosphate, triphenyl phosphate, fluoroalkyl phosphate, cresol diphenyl phosphate, diphenyl octyl phosphate, tributyl phosphate, trimethyl phosphate, isopropylphenyl diphenyl Phosphate esters, tris(4-methoxyphenyl) phosphate, toluene diphenyl phosphate, diphenyl octyl phosphate, trioctyl phosphate, triethyl phosphate, vinyl ethyl phosphate, tris(β-chloroethyl) phosphate, tris(2,2,3,3,3-pentafluoropropyl) phosphate, tris(1,1,1,3,3,3-fluoro-2-propyl) phosphate, phosphite flame retardants, trimethyl phosphite, triphenyl phosphite, triethyl phosphite, tributyl phosphite Tris(2,2,2-trifluoroethyl) phosphite, phosphite triesters, phosphonate flame retardants, dimethyl methylphosphonate, diethyl ethylphosphonate, diethyl phenylphosphonate, bis(2,2,2-trifluoroethyl) methylphosphonate, bis(2,2,2-trifluoroethyl) ethylphosphonate, diethyl 2-(thiophenemethyl)phosphonate, hexamethoxycyclotriphosphazene, hexa(methoxyethoxyethoxy)cyclotriphosphazene, unsaturated alkoxycyclotriphosphazene, hexa( One or more of the following: 2,2,2-trifluoroethoxy)cyclotriphosphazene, ethoxypentafluorocyclotriphosphazene, phenoxypentafluorocyclotriphosphazene, 4-methoxy-phenoxypentafluorocyclotriphosphazene, 2-chloro-4-methoxy-phenoxypentafluorocyclotriphosphazene, poly[bis(methoxyethoxyethoxy)phosphazene], poly[bis(ethoxyethoxyethoxy)phosphazene], small phosphazene molecules, hexafluorocyclotriphosphazene, ethoxy(pentafluoro)cyclotriphosphazene, and hexachlorocyclotriphosphazene.

[0019] More preferably, the fire-fighting heat-conducting medium is perfluoroketone; more preferably, the fire-fighting heat-conducting medium is perfluorohexanone.

[0020] Furthermore, the heat pipe body is also provided with a weak section. Further, the weak section is a groove provided on the heat pipe body.

[0021] Furthermore, the self-destruct device is located at the bottom of the heat pipe body.

[0022] Furthermore, a stabilizing component is also provided outside the self-destruct device. Preferably, the stabilizing component is a rubber body or retaining spring that elastically fits tightly against the heat pipe body. More preferably, the stabilizing component can be a recessed locking position provided on the heat pipe body.

[0023] More preferably, the heat pipe also has a liquid-absorbing core.

[0024] More preferably, the liquid-absorbing core is a foamed copper sintered liquid-absorbing core.

[0025] Furthermore, the heat pipe is evacuated, and the fire-fighting heat-conducting medium is injected into the vacuum state.

[0026] Compared with the prior art, this application has the following beneficial effects:

[0027] 1) Utilizing the heat pipe heat conduction principle, a heat-conducting working fluid with fire extinguishing capabilities is added to the heat pipe cavity. When the temperature does not exceed the threshold, the heat-conducting working fluid can achieve temperature equalization inside the battery or battery box; or transfer heat to the cooling device connected to the heat pipe body to achieve heat management of the battery.

[0028] 2) When the temperature inside the battery or battery box is too high, the temperature inside the heat pipe will increase accordingly. When the temperature of the heat pipe reaches the threshold, the self-destruct device inside the heat pipe body will be activated. The pressure generated will cause the weak part of the heat pipe body to burst open, releasing the heat-conducting working fluid with fire extinguishing ability, thereby preventing or extinguishing the fire inside the battery or battery box.

[0029] Other advantages, objectives and features of this application will be partly apparent from the description below, and partly understood by those skilled in the art through study and practice of this application. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the appearance of the heat pipe in this application.

[0032] Figure 2 This is a schematic cross-sectional view of the heat pipe in Embodiment 1 of this application.

[0033] Figure 3 This is a schematic diagram of the combination of the retaining ring and the blasting device in Embodiment 2 of this application.

[0034] Figure 4 This is a schematic cross-sectional view of the heat pipe in Embodiment 2 of this application.

[0035] Figure 5 This is a schematic cross-sectional view of the heat pipe in Embodiment 4 of this application. Detailed Implementation

[0036] The present application will now be described in further detail with reference to the accompanying drawings, so that those skilled in the art can implement it based on the description.

[0037] It should be understood that terms such as “having,” “comprising,” and “including” as used herein do not imply the presence or addition of one or more other elements or combinations thereof.

[0038] The technical solution of this application will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0039] Example 1

[0040] This application discloses a self-exploding heat pipe for batteries, comprising a heat pipe body 1 with a hollow structure, wherein a fire-fighting heat-conducting medium is stored within the hollow structure of the heat pipe body 1; a self-exploding device 3 is provided within the heat pipe body; when the heat pipe temperature reaches a threshold, the self-exploding device 3 within the heat pipe body 1 is activated, and the resulting pressure causes the weak part of the heat pipe body 1 to burst, releasing the fire-fighting heat-conducting medium, thereby preventing or extinguishing a fire inside the battery or battery box.

[0041] Example 2

[0042] like Figure 1 and Figure 2 As shown, a self-destructing device 3 with a rubber body 4 is inserted into the bottom of the heat pipe body 1, and the self-destructing device 3 is fixed to the heat pipe body by the rubber body 4. The self-destructing device 3 contains a temperature-sensitive self-ignition agent that can be activated at 160°C. The heat pipe body 1 is then evacuated, injected with perfluorohexanone, and sealed to obtain the self-venting heat pipe of this application.

[0043] When the temperature inside the heat pipe reaches the activation temperature of the heat-sensitive self-igniting agent, the self-destruct device 3 is activated, causing the pressure inside the heat pipe to rise rapidly. This causes the groove 2 on the heat pipe body 1 to burst open, forming a release channel. The fire-fighting heat-conducting medium inside the heat pipe body is then ejected from the release channel, thereby achieving the purpose of preventing or extinguishing fires inside the battery or battery box.

[0044] Example 3

[0045] like Figure 3 and Figure 4 As shown, a self-destructing device 3 with a retaining spring 5 is inserted into the bottom of the heat pipe body 1. The retaining spring 5 secures and fixes the self-destructing device 3 inside the heat pipe. The self-destructing device 3 contains a temperature-sensitive auto-ignition agent and a gas-generating agent. The ignition temperature of the temperature-sensitive auto-ignition agent is 150°C. The heat pipe body 1 is evacuated, trifluoromethane is injected, and the end is sealed to obtain the self-venting heat pipe of this application.

[0046] When the temperature inside the heat pipe reaches the activation temperature of the heat-sensitive self-igniting agent, the self-destruct device 3 is activated, further igniting the gas-generating agent and producing a large amount of gas. This causes the pressure inside the heat pipe to rise rapidly, which in turn causes the weak part of the heat pipe body to burst open, forming a release channel. The fire-fighting heat-conducting medium inside the heat pipe body is sprayed out from the release channel, thereby achieving the purpose of preventing or extinguishing fires inside the battery or battery box.

[0047] Example 4

[0048] like Figure 5 As shown, a self-destructing device 3 is inserted into the bottom of the heat pipe body 1, and then a recessed locking position 6 is set at a corresponding position on the heat pipe body to fix the self-destructing device 3 to the bottom of the heat pipe body 1. The self-destructing device 3 contains a temperature-sensitive self-ignition agent and a gas-generating agent, and the ignition temperature of the temperature-sensitive self-ignition agent is 170°C. The heat pipe body 1 is evacuated, trimethyl phosphate is injected, and the end is sealed to obtain the self-venting explosion heat pipe of this application.

[0049] It is understood that the recessed locking position can be made by directly machining or stamping the heat pipe body to create a recess in the heat pipe body, and the self-destruct device 3 can be locked and fixed in the corresponding position through the recessed part.

[0050] When the temperature inside the heat pipe reaches the activation temperature of the heat-sensitive self-igniting agent, the self-destruct device 3 is activated, further igniting the gas-generating agent and producing a large amount of gas. This causes the pressure inside the heat pipe to rise rapidly, which in turn causes the weak part of the heat pipe body to burst open, forming a release channel. The fire-fighting heat-conducting medium inside the heat pipe body is sprayed out from the release channel, thereby achieving the purpose of preventing or extinguishing fires inside the battery or battery box.

[0051] Although the embodiments of this application have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for this application. Other modifications can be readily implemented by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, this application is not limited to the specific details and examples shown and described herein.

Claims

1. A self-venting heat pipe for a battery, comprising a heat pipe body having a hollow structure, characterized in that, The hollow structure of the heat pipe body stores the fire-fighting heat-conducting medium. The heat pipe body is equipped with a self-destruct device; the agent in the self-destruct device is sealed and stored in a metal shell, which is compatible with the fire-fighting heat-conducting medium. When the heat pipe temperature reaches the threshold, the self-destruct device inside the heat pipe body is activated, and the pressure generated causes the weak part of the heat pipe body to burst open, releasing the fire-fighting heat-conducting medium; the weak part is a groove provided on the heat pipe body. The self-destruct device contains a heat-sensitive self-ignition agent that can be activated within a specific temperature threshold. The self-destruct device also contains a gas-generating agent.

2. The self-venting heat pipe for a battery as described in claim 1, characterized in that, The self-starting temperature threshold range of the aforementioned temperature-sensitive self-ignition agent is 150℃~200℃.

3. The self-venting heat pipe for a battery as described in claim 1, characterized in that, The metal casing is a copper casing or an aluminum casing.

4. A self-venting heat pipe for a battery as described in claim 1, characterized in that, The self-destruct device is located at the bottom of the heat pipe body.

5. A self-venting heat pipe for a battery as described in claim 1, characterized in that, The self-destruct device is also equipped with a stabilizing component.

6. A self-venting heat pipe for a battery as described in claim 5, characterized in that, The stabilizing component is a rubber body or a retaining spring that is elastically and tightly attached to the heat pipe body.

7. A self-venting heat pipe for a battery as described in claim 5, characterized in that, The stabilizing component is a recessed locking position set at a corresponding position on the heat pipe body.

8. A self-venting heat pipe for a battery as described in claim 1, characterized in that, The heat pipe also has a liquid wick inside.

9. A self-venting heat pipe for a battery as described in claim 8, characterized in that, The liquid-absorbing core is a sintered copper foam liquid-absorbing core.

10. A self-venting heat pipe for a battery as described in claim 1, characterized in that, The heat pipe is filled with the fire-fighting heat-conducting medium under vacuum.

11. A self-venting heat pipe for a battery as described in claim 10, characterized in that, The fire-fighting heat-conducting medium is one or more of perfluorohexanone, pentafluoroethane, difluoromethane, trifluoromethane, and tris(2,2,2-trifluoroethyl) phosphite.

12. A self-venting heat pipe for a battery as described in claim 11, characterized in that, The heat-conducting medium for fire protection is perfluorohexanone.

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