Battery thermal runaway triggering device

Abstract

The utility model relates to a battery thermal runaway triggering device. The battery thermal runaway triggering device comprises a pricking needle, the pricking needle comprises a needle body and a needle head located at one end of the needle body, the pricking needle is configured to be capable of pricking into a shell of a battery cell, and a containing cavity is formed in the needle head; the energy source module is arranged in the containing cavity in the needle head, and the energy source module is configured to be capable of being activated to release energy; wherein the needle head is provided with an energy release structure, and the energy release structure is configured to allow energy generated by the energy source module to be released out of the needle head so as to trigger thermal runaway in the battery cell. According to the battery thermal runaway triggering device, the test working condition of the battery thermal runaway spreading test is closer to the real thermal runaway working condition of the battery cell in the actual use scene, so that the test result can more truly reflect the safety of the battery device in the actual use.

Description

Technical Field

[0001] This application relates to the field of battery safety testing technology, and in particular to a battery thermal runaway triggering device. Background Technology

[0002] In the field of lithium battery safety testing, thermal runaway propagation testing is a crucial step in assessing battery safety. Thermal runaway propagation testing involves triggering thermal runaway in one cell of the battery device and observing whether it induces a chain reaction of thermal runaway in other cells.

[0003] Common methods for triggering thermal runaway include built-in heating films, external heating plates, and needle penetration. For national standard spot checks in the market, since it is impossible to pre-install heating elements inside the battery device, and the cells inside the battery device are densely packed, needle penetration of selected cells from the bottom of the battery device has become a feasible triggering method.

[0004] As the requirements for the realism of test conditions become increasingly stringent, it is necessary to optimize the existing bottom needle penetration triggering method so that the test results can more realistically reflect the safety of the battery device in actual use. Utility Model Content

[0005] Therefore, it is necessary to address the issue that existing thermal runaway propagation tests use bottom-puncture methods to trigger thermal runaway in battery cells, which significantly tightens the test conditions and causes the test results to fail to accurately reflect the safety of the battery device during actual use. A battery thermal runaway triggering device should be provided.

[0006] This application provides a battery thermal runaway triggering device, comprising:

[0007] A piercing needle, comprising a needle body and a needle tip located at one end of the needle body, the piercing needle being configured to penetrate the housing of a battery cell, the needle tip having a receiving cavity; and

[0008] An energy source module is disposed within a cavity inside the needle, and the energy source module is configured to be activated to release energy.

[0009] The needle tip is provided with an energy release structure, which is configured to allow the energy generated by the energy source module to be released outside the needle tip to trigger thermal runaway inside the battery cell.

[0010] In one embodiment, the energy release structure includes a through-hole communicating with the accommodating cavity.

[0011] In one embodiment, the number of through holes is one; or, the number of through holes is multiple; when the number of through holes is multiple, the multiple through holes are arranged sequentially at intervals along the circumference of the needle.

[0012] In one embodiment, the needle is configured as a tip that tapers gradually along the insertion direction, and the energy release structure is disposed on the side of the needle.

[0013] In one embodiment, the energy source module includes an energy source and a trigger, wherein the energy source is a chemically exothermic substance, and the trigger is configured to ignite the chemically exothermic substance to cause the chemically exothermic substance to release heat energy.

[0014] In one embodiment, the trigger is any one or a combination of a high-voltage electrode pair, a laser generator, and a microwave antenna.

[0015] In one embodiment, the chemically exothermic substance includes any one or more of the following: aluminothermic, magnesothermic, silicothermic, and boronothermic.

[0016] In one embodiment, the energy source module includes an energy source, which is any one or a combination of a high-voltage electrode pair, a microwave antenna, and a laser generator.

[0017] In one embodiment, the needle body has a channel for a wire connected to the energy source module to pass through.

[0018] In one embodiment, the battery thermal runaway triggering device further includes a partition, which is located in the cavity inside the needle and is sealed to the cavity wall to divide the cavity into the receiving cavity and the channel.

[0019] In one embodiment, the partition includes a mounting base on which the energy source module is mounted.

[0020] In one embodiment, the battery thermal runaway triggering device further includes a sealing sleeve, which is fitted onto the needle; the inner wall of the sealing sleeve and the outer wall of the needle are sealed together, and the sealing sleeve and the needle are movable relative to each other and have resistance to movement;

[0021] The end face of the sealing sleeve near the needle is configured to seal against the housing of the battery cell.

[0022] In one embodiment, the end face of the sealing sleeve near the needle tip is provided with an adhesive portion.

[0023] In one embodiment, a damping seal is provided between the inner wall of the sealing sleeve and the outer wall of the needle, the damping seal being configured to provide resistance to movement while allowing relative movement between the sealing sleeve and the needle.

[0024] In one embodiment, the damping seal is an oil film.

[0025] When the aforementioned battery thermal runaway triggering device is used for battery thermal runaway propagation testing, the needle tip of the piercing needle is inserted into the cell casing. The needle tip carries the energy source module within its accommodating cavity a into the cell casing. The energy source module is activated to release energy. Because the energy release structure is configured to allow the energy generated by the energy source module to be released outside the needle tip, and the needle tip is located inside the cell casing, the energy released by the energy source module can act on the electrode assembly inside the cell, thereby triggering thermal runaway. The needle only needs to be near the electrode; the energy released through the energy release structure on the needle tip can act on the electrode assembly (including the electrode, separator, etc.), thereby triggering thermal runaway. Therefore, the needle does not need to contact the electrode or only slightly contacts it, avoiding the severe deformation of the electrode caused by pushing it during traditional needle piercing methods. This allows the test conditions for battery thermal runaway propagation testing to more closely resemble the actual thermal runaway conditions of the cell in real-world usage scenarios, thus enabling the test results to more realistically reflect the safety of the battery device during actual use. It also avoids the situation where the needle causes a local short circuit in the cell, a decrease in cell SOC, and electrolyte leakage during the pushing process of the electrode, thus reducing the probability of trigger failure. Attached Figure Description

[0026] Figure 1 This is a diagram of a battery thermal runaway triggering device according to one embodiment.

[0027] Figure 2 for Figure 1 A magnified view of a portion of region A in the middle.

[0028] Figure 3 for Figure 1 A schematic diagram of the structure of the central puncture needle.

[0029] Figure 4 for Figure 3 A magnified view of a portion of region B in the middle.

[0030] Explanation of reference numerals in the attached drawings: 100, needle; 110, needle body; 120, needle tip; 121, energy release structure; 101, cavity; 101a, accommodating cavity; 101b, channel; 200, energy source module; 210, energy source; 220, trigger; 300, partition; 400, wire; 500, sealing sleeve; 600, adhesive part; 700, damping sealing part. Detailed Implementation

[0031] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0032] In the description of this application, it should be understood that if terms such as "length", "inner", "outer", "circumferential", etc. appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0033] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0034] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "fixation," etc., shall be interpreted broadly. For example, they may refer to a fixed connection, a detachable connection, or an integral part; they may refer to a mechanical connection or an electrical connection; they may refer to a direct connection or an indirect connection through an intermediate medium; they may refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0035] In this application, unless otherwise expressly specified and limited, if a description such as "above" or "below" the second feature appears, it means that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium.

[0036] It should be noted that if a component is described as "fixed to" or "set on" another component, it can be directly on the other component or there may be an intervening component. If a component is described as "connected to" another component, it can be directly connected to the other component or there may be an intervening component.

[0037] As mentioned in the background section, national standard spot checks in the market typically employ a triggering method involving piercing selected cells from the bottom of the battery device. When the needle pierces the cell from the bottom, the piercing direction is parallel to the height direction of the electrode. However, the electrode is flexible, so the needle cannot directly pierce it; it pushes it upwards a certain distance before piercing the electrode, causing an internal short circuit and triggering thermal runaway. During this pushing process, the electrode undergoes severe deformation, making the test conditions more stringent than the actual thermal runaway conditions of the cell in real-world usage scenarios. This significantly tightens the test conditions, resulting in test results that do not accurately reflect the safety of the battery device in actual use. Furthermore, the needle may prematurely cause a localized short circuit within the cell during the pushing process, leading to a decrease in the cell's SOC (State of Charge) and electrolyte leakage, ultimately causing triggering failure.

[0038] Based on the above problems, this application provides a battery thermal runaway triggering device. The needle 120 can carry the energy source module 200 within its accommodating cavity 101a into the cell housing. The energy release structure 121 is configured to allow energy generated by the energy source module 200 to be released outside the needle 120. This allows the energy released by the energy source module 200 to act on the electrode assembly inside the cell, thereby triggering thermal runaway. The needle 120 does not need to contact the electrode or only slightly contacts it, avoiding the severe deformation of the electrode caused by pushing it during traditional needle piercing methods. This allows the test conditions for battery thermal runaway propagation testing to more closely resemble the actual thermal runaway conditions of the cell in real-world usage scenarios, thus enabling the test results to more realistically reflect the safety of the battery device during actual use.

[0039] Figure 1 This is a diagram of a battery thermal runaway triggering device according to one embodiment. Figure 2 for Figure 1 A magnified view of a portion of region A in the middle. Figure 3 for Figure 1 A schematic diagram of the structure of the central puncture needle. Figure 4 for Figure 3 A magnified view of a portion of region B in the middle.

[0040] Please see Figure 1 and Figure 2 One embodiment of this application provides a battery thermal runaway triggering device, which includes a needle 100 and an energy source module 200.

[0041] refer to Figure 3The needle 100 includes a needle body 110 and a needle tip 120 located at one end of the needle body 110. The needle 100 is configured to penetrate into the housing of the battery cell, and the needle tip 120 has a receiving cavity 101a. An energy source module 200 is disposed in the receiving cavity 101a within the needle tip 120, and the energy source module 200 is configured to be activated to release energy.

[0042] The needle 120 is provided with an energy release structure 121, which is configured to allow the energy generated by the energy source module 200 to be released outside the needle 120 to trigger thermal runaway inside the battery cell.

[0043] The needle tip 120 and the needle body 110 are integrally formed. The piercing needle 100 pierces into the housing of the battery cell through the needle tip 120.

[0044] When the aforementioned battery thermal runaway triggering device is used for battery thermal runaway propagation testing, the needle 120 of the piercing needle 100 is inserted into the cell housing. The needle 120 carries the energy source module 200 within its accommodating cavity 101a into the cell housing. The energy source module 200 is activated to release energy. Since the energy release structure 121 is configured to allow the energy generated by the energy source module 200 to be released outside the needle 120, and the needle 120 is located inside the cell housing, the energy released by the energy source module 200 can act on the electrode assembly inside the cell, thereby triggering thermal runaway. The needle 120 only needs to be near the electrode; the energy released through the energy release structure 121 on the needle 120 can act on the electrode assembly (including the electrode, separator, etc.), thereby triggering thermal runaway. Therefore, the needle 120 does not need to contact the electrode or only makes slight contact, avoiding the severe deformation of the electrode caused by pushing it down in traditional needle piercing methods. This allows the test conditions for battery thermal runaway propagation testing to more closely resemble the actual thermal runaway conditions of the battery cell in real-world usage scenarios, thus enabling the test results to more accurately reflect the safety of the battery device in actual use. It also avoids the possibility of the needle causing premature local short circuits, a decrease in cell SOC, and electrolyte leakage during the pushing process, reducing the probability of trigger failure.

[0045] Taking the application of heat energy to electrode components (including electrodes, separators, etc.) as an example, the separator (mostly made of polymer materials) used to isolate the positive and negative electrodes has weak heat resistance. Heat energy will cause it to soften, shrink or even rupture rapidly, losing its insulating function. This will lead to direct contact between the positive and negative electrode materials, causing an internal short circuit in the battery cell. The internal short circuit will further generate a large amount of Joule heat, causing the internal temperature of the battery cell to rise sharply, forming a heat accumulation effect. The high temperature will also trigger a violent exothermic side reaction between the electrode material (such as positive electrode transition metal oxides and negative electrode carbon materials) and the electrolyte, releasing more heat and flammable gases. This additional heat will continue to aggravate the extent of separator rupture and accelerate the side reaction process, forming a thermal runaway chain reaction.

[0046] It should be noted that when the aforementioned battery thermal runaway triggering device is used to conduct thermal runaway propagation tests on the battery device, a clearance hole can be pre-drilled at the bottom of the battery device housing. After the piercing needle 100 passes through the clearance hole, it can contact the bottom of the cell housing and thus penetrate into the cell housing. The piercing needle 100 does not need to pierce the bottom of the battery device housing.

[0047] In other embodiments, the above-mentioned battery thermal runaway triggering device is not limited to being inserted from the bottom of the cell casing, but can also be inserted from the large surface of the cell casing to trigger thermal runaway.

[0048] Please combine Figure 2 and Figure 4 In one embodiment, the energy release structure 121 includes a through hole communicating with the accommodating cavity 101a.

[0049] The number of through holes can be one or more. When there are multiple through holes, they are arranged sequentially at intervals along the circumference of the needle tip 120, allowing energy to be released from each through hole individually. Figure 4 In the middle, the two through holes are located on opposite sides of the needle tip 120.

[0050] When the energy source module 200 is activated, the through hole can serve as an energy transmission channel, guiding the energy generated by the energy source module 200 to be transmitted to the outside of the needle 120 through the through hole, thereby ensuring that the energy can act on the electrode inside the cell housing to trigger thermal runaway.

[0051] In other alternative embodiments, the energy release structure 121 may also be a high-temperature resistant metal mesh or ceramic grid, disposed on the side of the needle 120.

[0052] In other alternative embodiments, the energy release structure 121 may also be a meltable sealing layer, such as sealing the through-hole with a low-melting-point metal foil (such as tin foil, aluminum foil) or a polymer film.

[0053] Please combine Figure 2 and Figure 4In one embodiment, the needle 120 is configured as a tip that tapers gradually along the insertion direction, and the energy release structure 121 is disposed on the side of the needle 120.

[0054] By constructing the needle 120 as a tip that gradually tapers along the insertion direction, the resistance when the needle 100 penetrates the battery cell housing can be reduced, making the insertion process smoother. At the same time, the energy release structure 121 is located on the side of the needle 120, which does not interfere with the needle 120 penetrating the battery cell housing, ensuring that the energy released by the energy source module 200 in the accommodating cavity 101a can be smoothly transferred to the inside of the battery cell outside the needle 120.

[0055] Please refer to Figure 2 In one embodiment, the energy source module 200 includes an energy source 210 and a trigger 220. The energy source 210 is a chemically exothermic substance, and the trigger 220 is configured to ignite the chemically exothermic substance to release heat energy.

[0056] Chemically exothermic substances include any one or more of the following: aluminothermic agents, magnesothermic agents, silicothermic agents, and boronothermic agents.

[0057] Once the needle 120 is inserted into the battery cell housing, the energy source module 200 needs to be activated. This can be achieved by activating the trigger 220, which generates ignition conditions (such as high temperature or sparks) to ignite the exothermic chemical substance serving as the energy source 210. The combustion of the exothermic chemical substance releases a large amount of stable heat energy. This heat energy is transferred to the inside of the battery cell through the energy release structure 121 (such as a through-hole) on the needle 120, acting on the electrode assembly and triggering thermal runaway within the battery cell.

[0058] This embodiment uses a chemically exothermic substance as the energy source 210. The heat energy released by the chemically exothermic substance is stable, continuous, and has a high heat density, which can effectively meet the temperature requirements for triggering thermal runaway of the battery cell, resulting in a high triggering success rate. A trigger 220 is used to ignite the chemically exothermic substance, offering strong controllability. The ignition action can be initiated only after the needle 100 has been fully inserted, avoiding the risks of premature partial short circuits, SOC drops, and electrolyte leakage associated with traditional needle-punching triggering methods.

[0059] Please refer to Figure 2 In one embodiment, the trigger 220 is a high-voltage electrode pair.

[0060] When the needle 120 pierces into the battery cell housing and reaches its position, it energizes the high-voltage electrode pair. Due to the high voltage, a high-voltage arc is generated between the electrode pairs. The high temperature released by the arc can directly ignite the chemical energy exothermic substance that serves as the energy source 210.

[0061] In this embodiment, a high-voltage electrode pair is used as the trigger 220. The high-voltage arc generated by the electrode pair has a high and concentrated temperature, which can quickly and fully ignite the chemically exothermic substance and easily trigger it successfully.

[0062] In other embodiments, the trigger 220 can also be a laser generator. When the needle 120 pierces into the battery cell housing and reaches its position, the laser generator is activated. The laser generator releases a high-energy-density laser beam, which is focused on the chemically exothermic material that serves as the energy source 210. The high energy of the laser beam can quickly break through the ignition threshold of the chemically exothermic material, causing it to be stably ignited and releasing a large amount of continuous heat energy during combustion.

[0063] Similarly, the trigger 220 can also be a microwave antenna. When the needle 120 pierces into the battery cell housing and is in place, it controls the microwave antenna to work. The microwave energy generated by the microwave antenna acts on the chemically exothermic material that serves as the energy source 210. The microwave energy can penetrate the surface of the chemically exothermic material, causing the molecules inside the material to vibrate rapidly and generate a large amount of internal heat. The heat is gradually accumulated until it breaks through the ignition threshold of the material, thereby stably igniting the chemically exothermic material.

[0064] In some embodiments, the trigger 220 may be any one or a combination of a high-voltage electrode pair, a microwave antenna, and a laser generator.

[0065] In other embodiments, the chemical energy exothermic substance may not be used as the energy source 210. The energy source 210 may be any one or a combination of high voltage electrode pairs, microwave antennas, and laser generators.

[0066] When the energy source 210 is a high-voltage electrode pair, after the needle 120 pierces into the battery cell housing and reaches its position, it supplies power to the high-voltage electrode pair. Due to the high voltage, a high-voltage arc is generated between the electrode pairs. The heat released by the arc can be released to the outside of the needle 120 through the energy release structure 121.

[0067] When the energy source 210 is a laser generator, after the needle 120 pierces into the battery cell housing and reaches its position, the laser generator is activated. The laser generator releases a high-energy-density laser beam, which acts on the electrode assembly through the energy release structure 121, thereby inducing thermal runaway.

[0068] When the energy source 210 is a microwave antenna, after the needle 120 pierces into the battery cell housing and reaches its position, the microwave antenna is controlled to work. The microwave energy generated by the microwave antenna acts on the electrode assembly through the energy release structure 121. The microwave energy causes the molecules inside the electrode assembly to vibrate rapidly and generate a large amount of internal heat, which can trigger thermal runaway.

[0069] Please combine Figure 2 and Figure 4In some embodiments, the needle body 110 has a channel 101b for the wire 400 connected to the energy source module 200 to pass through.

[0070] The wire 400 can be used to connect a power supply and / or control device to the energy source module 200 to provide electrical power to the energy source module 200 and / or control the activation of the energy source module 200.

[0071] For example, the high-voltage electrode pair can be connected to an external high-voltage power supply (providing the high-voltage electrical energy required to generate the electric arc) and a controller (controlling the timing and parameters of power-on) via wire 400. The laser generator can be connected to an external laser drive power supply (providing the electrical energy required for laser emission) and a controller (transmitting control signals such as start / stop and power adjustment) via wire 400. The microwave antenna can be connected to an external microwave drive power supply (providing the electrical energy required to generate microwaves) and a controller (transmitting control signals such as start / stop and microwave parameter adjustment) via wire 400.

[0072] In this embodiment, a channel 101b is provided inside the needle body 110, through which the wire 400 passes, providing protection for the wire 400 without interfering with the insertion action of the needle 100.

[0073] Please refer to Figure 2 In one embodiment, the battery thermal runaway triggering device further includes a partition 300, which is located in the cavity 101 inside the needle 100 and is sealed to the cavity wall of the cavity 101 to divide the cavity 101 into a receiving cavity 101a and a channel 101b.

[0074] One end of the wire 400 can be inserted into the partition 300 and connected to the energy source module 200.

[0075] In this embodiment, the partition 300 is sealed to the cavity wall within the internal cavity 101 of the needle 100.

[0076] The cavity 101 is divided into a receiving cavity 101a and a channel 101b located on both sides of the partition 300. In this way, the partition 300 can prevent the energy (such as heat, electric arc, microwave, etc.) released by the energy source module 200 in the receiving cavity 101a from diffusing into the channel 101b, so that the energy is guided to the energy release structure 121 of the needle 120 and released to the outside of the needle 120, thereby reducing energy loss and affecting the triggering success rate, and ensuring the accuracy and efficiency of thermal runaway triggering.

[0077] In one embodiment, the partition 300 includes a mounting base on which the energy source module 200 is mounted.

[0078] For example, high-voltage electrode pairs can be mounted on a mounting base. Microwave antennas can be mounted on a mounting base. Laser generators can be mounted on a mounting base.

[0079] The outer surface of the mounting base can directly contact the cavity wall of the cavity 101, or a sealing ring can be provided between the outer surface of the mounting base and the cavity wall of the cavity 101, and the partition 300 can be sealed to the cavity wall of the cavity 101.

[0080] In this embodiment, the mounting base in the partition 300 can be used to install the energy source module 200 to support the energy source module 200, and can also be used to isolate the accommodating cavity 101a and the channel 101b, thus achieving a dual function without the need for additional independent mounting bases and partitions, reducing the complexity of the device.

[0081] Please refer to Figure 1 In one embodiment, the battery thermal runaway triggering device further includes a sealing sleeve 500, which is sleeved on the needle 100. The inner wall of the sealing sleeve 500 is in a sealing fit with the outer wall of the needle 100, and the sealing sleeve 500 and the needle 100 are movable relative to each other with resistance to movement. The end face of the sealing sleeve 500 near the needle tip 120 is configured to be in a sealing fit with the housing of the battery cell.

[0082] The sealing sleeve 500 can be made of high-temperature resistant and high-strength rubber material.

[0083] When the aforementioned battery thermal runaway triggering device is used to conduct a battery thermal runaway propagation test, the process of the needle 100 penetrating the inside of the cell housing is as follows: First, due to the movement resistance between the sealing sleeve 500 and the needle 100, the sealing sleeve 500 and the needle 100 can move synchronously before the sealing sleeve 500 contacts the cell housing; then, as the needle 100 gradually penetrates into the cell housing, the sealing sleeve 500 abuts against the outer surface of the cell housing and seals with the outer surface of the cell housing, thereby forming a first sealing interface between the end face of the sealing sleeve 500 and the outer surface of the cell housing; as the needle 100 continues to penetrate into the cell housing, the end face of the sealing sleeve 500 cannot continue to move due to its contact with the outer surface of the cell housing, thus the needle 100 overcomes the movement resistance between itself and the sealing sleeve 500 and continues to move until it penetrates to the end, triggering thermal runaway.

[0084] When the needle 100 is inserted and the energy source module 200 is activated, triggering thermal runaway within the battery cell, high-pressure gas is generated inside the cell, and this high-pressure gas tends to eject outwards. A first sealing interface is formed between the end face of the sealing sleeve 500 and the outer surface of the battery cell housing, and a second sealing interface is formed between the inner wall of the sealing sleeve 500 and the outer wall of the needle 100 through a sealing fit. These first and second sealing interfaces prevent the high-pressure gas from escaping, ensuring the battery cell's airtightness during testing. The high-pressure gas exerts a force on the sealing sleeve 500 towards the outside of the battery cell housing. The bonding force between the sealing sleeve 500 and the battery cell housing at the first sealing interface, as well as the movement resistance between the sealing sleeve 500 and the needle 100, resists the force from the high-pressure gas, ensuring that the sealing sleeve 500 reliably seals with both the battery cell housing and the needle 100.

[0085] Please refer to Figure 1 In one embodiment, the end face of the sealing sleeve 500 near the needle 120 is provided with an adhesive portion 600.

[0086] The bonding part 600 can be made of acrylic adhesive or other adhesive materials.

[0087] As the needle 100 gradually penetrates into the battery cell housing, the adhesive portion 600 on the end face of the sealing sleeve 500 abuts against the outer surface of the battery cell housing, thereby making the end face of the sealing sleeve 500 firmly connected and sealed to the outer surface of the battery cell housing, thus facilitating the formation of the aforementioned first sealing interface during the insertion of the needle 100.

[0088] Please refer to Figure 1 In one embodiment, a damping seal 700 is provided between the inner wall of the sealing sleeve 500 and the outer wall of the needle 100. The damping seal 700 is configured to provide resistance to movement while allowing relative movement between the sealing sleeve 500 and the needle 100.

[0089] The damping effect of the damping seal 700 can create movement resistance between the sealing sleeve 500 and the needle 100. At the same time, the damping seal 700 can play a sealing role between the inner wall of the sealing sleeve 500 and the outer wall of the needle 100, thereby facilitating the formation of a second sealing interface.

[0090] Optionally, the damping seal 700 can be an oil film, which utilizes its viscosity to create movement resistance between the sealing sleeve 500 and the needle 100. The oil film provides a smooth and continuous viscous resistance, thereby precisely controlling the dynamic process of the sealing sleeve and the needle moving synchronously and then relative to each other. At the same time, the oil film can seamlessly fill all micro-gaps, achieving a more reliable dynamic seal and effectively buffering the internal pressure impact during thermal runaway, thus providing a more stable and smoother sealing effect throughout the insertion and triggering process.

[0091] Alternatively, the damping seal 700 can also be an elastic sealing ring, etc.

[0092] In other embodiments, the damping sealing part 700 may not be provided between the inner wall of the sealing sleeve 500 and the outer wall of the needle 100. The sealing sleeve 500 itself may be made of an elastic material. In this way, the elastic abutment between the sealing sleeve 500 and the outer wall of the needle 100 can provide resistance to movement, and the two can maintain a seal.

[0093] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0094] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A battery thermal runaway trigger device, characterized by, The application relates to a safety device for an electric battery, comprising: a piercing needle comprising a needle body and a needle head located at one end of the needle body, the needle head being provided with a receiving cavity, and an energy source module located in the receiving cavity of the needle head, the energy source module being configured to be activated to release energy; wherein the needle head is provided with an energy release structure configured to allow the energy released by the energy source module to be released to the outside of the needle head to trigger thermal runaway inside the electric battery. The energy release structure comprises a through hole in communication with the receiving cavity. The number of through holes is one or multiple. When the number of through holes is multiple, the multiple through holes are arranged along the circumference of the needle head. The needle head is configured as a tapered tip gradually tapered in the piercing direction, and the energy release structure is located on the side surface of the needle head.

2. The battery thermal runaway trigger device of claim 1, wherein, The energy source module comprises an energy source and a trigger, the energy source being a chemical heat releasing substance, and the trigger being configured to ignite the chemical heat releasing substance to release heat energy.

3. The battery thermal runaway trigger device of claim 2, wherein, The trigger is any one or a combination of multiple of a high-voltage electrode pair, a laser generator and a microwave antenna. The chemical heat releasing substance comprises any one or multiple of an aluminum thermal agent, a magnesium thermal agent, a silicon thermal agent and a boron thermal agent.

4. The battery thermal runaway trigger device of claim 1, wherein, The energy source module comprises an energy source, which is any one or a combination of multiple of a high-voltage electrode pair, a microwave antenna and a laser generator.

5. The battery thermal runaway trigger device of any one of claims 1-4, wherein, The needle body is provided with a channel for a wire connected with the energy source module to pass through.

6. The battery thermal runaway trigger device of claim 5, wherein, The safety device further comprises a partition located in the cavity inside the piercing needle and in sealing connection with the cavity wall of the cavity to divide the cavity into the receiving cavity and the channel.

7. The battery thermal runaway trigger device of claim 5, wherein, The partition comprises a mounting seat, and the energy source module is mounted on the mounting seat.

8. The battery thermal runaway trigger device of any one of claims 1-4, wherein, The safety device further comprises a sealing sleeve sleeved on the piercing needle, the inner wall of the sealing sleeve being in sealing connection with the outer wall of the piercing needle, the sealing sleeve being capable of moving relative to the piercing needle and having a moving resistance.

9. The battery thermal runaway trigger device of claim 1, wherein, The end face of one end of the sealing sleeve close to the needle head is configured to be in sealing connection with the shell of the electric battery.

10. The battery thermal runaway trigger device of claim 9, wherein, The end face of one end of the sealing sleeve close to the needle head is provided with an adhesive part.

11. The battery thermal runaway trigger device of claim 10, wherein, The inner wall of the sealing sleeve and the outer wall of the piercing needle are provided with a damping sealing part configured to provide the moving resistance while allowing the sealing sleeve to move relative to the piercing needle.

12. The battery thermal runaway trigger device of claim 1, wherein, The damping sealing part is an oil film. ​ 13. The battery thermal runaway trigger device of claim 12, wherein, ​ 14. The battery thermal runaway trigger device of claim 12, wherein, ​ 15. The battery thermal runaway trigger device of claim 14, wherein, ​

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