Acupuncture thermal runaway prevention device for battery and battery

Abstract

The invention relates to the technical field of batteries, particularly provides a needling thermal runaway prevention device for a battery and the battery, and aims to solve the problem of needling thermal runaway of an existing battery. In order to achieve the purpose, the acupuncture thermal runaway prevention device comprises a trigger response mechanism and a dredging circuit, the trigger response mechanism is installed between a shell and a battery cell of the battery, the dredging circuit is installed on the outer side of the shell, the first end of the dredging circuit is electrically connected with the trigger response mechanism, and the second end of the dredging circuit is electrically connected with a first electrode of the battery cell; the trigger response mechanism is arranged to be capable of electrically connecting the first end of the dredging circuit with the second electrode of the battery cell when the trigger response mechanism is punctured, so that the dredging circuit releases energy of the battery cell to avoid thermal runaway of the battery. Through the dredging circuit and the trigger response mechanism which are matched with each other, energy dredging is rapidly achieved when acupuncture occurs, and thermal runaway caused by short-circuit temperature rise accumulation can be avoided.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and specifically provides a battery acupuncture thermal runaway prevention device and a battery. Background Technology

[0002] As the energy crisis and environmental pollution problems become increasingly serious worldwide, people's requirements for automobile energy conservation and emission reduction are gradually increasing. New energy vehicles have attracted more and more attention due to their low noise, pollution-free and high energy efficiency, thus promoting the accelerated development of new energy vehicles. At present, new energy vehicles usually use batteries as a power source, which provides a broad space for the application and development of batteries.

[0003] However, there are still several technical bottlenecks that need to be solved. The most critical one is the safety of the battery cell, such as the thermal runaway problem caused by needle puncture, for which there is no good solution until now.

[0004] Therefore, this field requires a new technical solution to solve the above problems. SUMMARY OF THE INVENTION

[0005] The present invention aims to solve the above technical problem, that is, to solve the problem of thermal runaway of existing batteries during needle puncture.

[0006] In a first aspect, the present invention provides a device for preventing thermal runaway by needle puncture for a battery, the battery comprising a shell and a battery cell installed in the shell, the device comprising a trigger response mechanism and a diversion circuit, the trigger response mechanism being installed between the shell and the battery cell, the diversion circuit being installed on the outside of the shell, the first end of the diversion circuit being electrically connected to the trigger response mechanism, the second end of the diversion circuit being electrically connected to the first electrode of the battery cell, the trigger response mechanism being configured to electrically connect the first end of the diversion circuit to the second electrode of the battery cell when being punctured, so that the diversion circuit releases the energy of the battery cell to avoid thermal runaway of the battery, wherein one of the first electrode and the second electrode is a positive electrode, and the other of the first electrode and the second electrode is a negative electrode.

[0007] In the preferred technical solution of the acupuncture thermal runaway prevention device for a battery, the trigger response mechanism includes a first collector film, a second collector film, and an insulating layer arranged between the first collector film and the second collector film, the first collector film is electrically connected to the second electrode, the second collector film is electrically connected to the first end of the drainage circuit, and the two sides of the insulating layer are respectively attached to the first collector film and the second collector film;

[0008] Alternatively, the trigger response mechanism includes a collector film and an insulating layer, the collector film is electrically connected to the first end of the draining circuit, one side of the insulating layer is bonded to the collector film, the other side of the insulating layer is bonded to the inner wall of the shell, and the shell is electrically connected to the second electrode;

[0009] Or, the trigger response mechanism includes a collector film and an insulating layer, the collector film is electrically connected to the first end of the drain circuit, one side of the insulating layer is bonded to the collector film, and the other side of the insulating layer is bonded to the second electrode.

[0010] In the preferred technical solution of the above-mentioned battery puncture thermal runaway prevention device, the elongation at break of the insulating layer is less than the elongation at break of the separator of the battery cell.

[0011] In the preferred technical solution of the above-mentioned battery puncture thermal runaway prevention device, the elongation at break of the insulating layer is less than half of the elongation at break of the separator of the battery cell.

[0012] In the preferred technical solution of the above-mentioned battery puncture thermal runaway prevention device, the thickness of the insulating layer is greater than 3 microns.

[0013] In the preferred technical solution of the above-mentioned battery puncture thermal runaway prevention device, the thickness of the insulating layer is less than half of the sum of the thickness of the first collector film and the thickness of the second collector film.

[0014] In the preferred technical solution of the above-mentioned battery puncture thermal runaway prevention device, the insulating layer is in a stretched state.

[0015] In the preferred technical solution of the acupuncture thermal runaway prevention device for batteries, the acupuncture thermal runaway prevention device further comprises a drainage electrode, the drainage electrode is mounted on the housing, and the first end of the drainage circuit is electrically connected to the trigger response mechanism through the drainage electrode.

[0016] In the preferred technical solution of the above-mentioned battery puncture thermal runaway prevention device, the resistance of the drainage circuit is greater than 1.2 times the resistance of the battery and less than 3.5 times the resistance of the battery.

[0017] In a second aspect, the present invention further provides a battery, the battery comprising the above-mentioned needle puncture thermal runaway prevention device for a battery.

[0018] ​In the case of adopting the above technical solution, the acupuncture thermal runaway prevention device of the present invention can prevent the battery from having acupuncture thermal runaway. Specifically, the acupuncture thermal runaway prevention device of the present invention includes a drainage circuit and a trigger response mechanism that cooperate with each other, which quickly realizes energy drainage when acupuncture occurs to avoid thermal runaway caused by the accumulation of short-circuit temperature rise, wherein the drainage circuit and the trigger response mechanism together constitute a puncture runaway control circuit, and the trigger response mechanism is equivalent to a special switch. At the beginning of the battery cell puncture, the switch is quickly closed, thereby quickly releasing the energy of the battery at the maximum allowable current, so that the ohmic heat caused by the internal short circuit of the battery cell due to the puncture is greatly reduced, and thermal runaway cannot be triggered, thereby avoiding the occurrence of thermal runaway.

[0019] Furthermore, the needle puncture thermal runaway prevention device of the present invention can effectively prevent the battery from thermal runaway under non-metal puncture conditions by making the elongation at break of the insulating layer smaller than the elongation at break of the diaphragm of the battery cell.

[0020] Furthermore, the needle puncture thermal runaway prevention device of the present invention can quickly trigger the trigger response mechanism under non-metallic puncture conditions by making the elongation at break of the insulating layer less than half of the elongation at break of the diaphragm of the battery cell, and can quickly release electricity before the battery cell is punctured and short-circuited, thus avoiding the risk of thermal runaway.

[0021] Furthermore, the acupuncture thermal runaway prevention device of the present invention puts the insulating layer in a stretched state, so that once punctured, the puncture hole will further expand under its own stress, thereby enabling the trigger response mechanism to trigger the action more accurately and quickly.

[0022] Furthermore, the acupuncture thermal runaway prevention device of the present invention can effectively avoid the occurrence of false triggering by setting the thickness of the insulating layer to be more than 3 microns.

[0023] Furthermore, the acupuncture thermal runaway prevention device of the present invention can effectively ensure the trigger sensitivity of the trigger response mechanism by setting the thickness of the insulating layer to be less than half of the sum of the thickness of the first collector film and the thickness of the second collector film.

[0024] Furthermore, the acupuncture thermal runaway prevention device of the present invention can ensure that the acupuncture thermal runaway accident can be avoided more effectively by making the resistance of the drainage circuit greater than 1.2 times the resistance of the battery and less than 3.5 times the resistance of the battery, so as to ensure that the drainage circuit has a sufficiently fast discharge speed and releases enough energy. Brief Description of the Figures

[0025] The following describes the preferred implementation of the present invention in conjunction with the accompanying drawings, in which:

[0026] Figure 1This is a schematic diagram of the working principle of the acupuncture thermal runaway prevention device of the present invention. Figure 1 ;

[0027] Figure 2 It is a schematic diagram of the working principle of the acupuncture thermal runaway prevention device of the present invention Figure 2 ;

[0028] Figure 3 is a schematic diagram of the exploded cylindrical battery of the present invention;

[0029] Figure 4 is a schematic diagram of the decomposition of the blade battery of the present invention;

[0030] Figure 5 This is a schematic diagram of the decomposition of the soft pack battery of the present invention.

[0031] List of Reference Numerals:

[0032] 1. Shell; 11. Positive pole;

[0033] 2. Battery cells;

[0034] 3. Trigger response mechanism; 31. First collector film; 32. Second collector film; 33. Insulation layer;

[0035] 4. Diversion circuit;

[0036] 5. Conducting electrode;

[0037] 6. Acupuncture needle. Specific implementation method

[0038] The following describes the preferred embodiments of the present invention with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0039] It should be noted that in the description of the present invention, the terms "inside", "outside", "upper", "lower", "top", "bottom" and other terms indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is only for the convenience of description, and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0040] ​In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and defined, the terms "arrangement", "connection", and "installation" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be an electrical connection or a mechanical connection. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] Specifically, the battery of the present invention includes a housing, an electric core, and a thermal runaway prevention device for needle puncture. The electric core is installed in the housing.

[0042] Among them, the thermal runaway prevention device for needle puncture includes a trigger response mechanism and a diversion circuit. The trigger response mechanism is installed between the housing and the electric core, and the diversion circuit is installed outside the housing. The first end of the diversion circuit is electrically connected to the trigger response mechanism, and the second end of the diversion circuit is electrically connected to the first electrode of the electric core. The trigger response mechanism is configured to be able to electrically connect the first end of the diversion circuit to the second electrode of the electric core when being needle punctured, so that the diversion circuit releases the energy of the electric core to avoid thermal runaway of the battery. Among them, one of the first electrode and the second electrode is the positive electrode, and the other of the first electrode and the second electrode is the negative electrode.

[0043] By adding a thermal runaway prevention device for needle puncture to the battery, the present invention can avoid thermal runaway of the battery caused by needle puncture.

[0044] Specifically, the thermal runaway prevention device for needle puncture of the present invention includes a mutually cooperating diversion circuit and a trigger response mechanism, which can quickly achieve energy diversion during needle puncture to avoid thermal runaway caused by the accumulation of short-circuit temperature rise. Among them, the diversion circuit and the trigger response mechanism jointly form a puncture runaway control circuit. The trigger response mechanism is equivalent to a special switch. At the initial stage of electric core puncture, the switch quickly closes, so as to quickly release the energy of the battery with the maximum allowable current, so that the ohmic heat caused by internal short circuit of the electric core due to puncture is greatly reduced and cannot trigger thermal runaway, thus avoiding the occurrence of thermal runaway.

[0045] It should be noted that in practical applications, those skilled in the art can also define the positive electrode of the electric core as the first electrode, and correspondingly, define the negative electrode of the electric core as the second electrode, that is, the second end of the diversion circuit is electrically connected to the positive electrode of the electric core, and the trigger response mechanism is configured to be able to electrically connect the first end of the diversion circuit to the negative electrode of the electric core when being needle punctured. Or, the negative electrode of the electric core can also be defined as the first electrode, and correspondingly, the positive electrode of the electric core can be defined as the second electrode, that is, the second end of the diversion circuit is electrically connected to the negative electrode of the electric core, and the trigger response mechanism is configured to be able to electrically connect the first end of the diversion circuit to the positive electrode of the electric core when being needle punctured.

[0046] In addition, it should be noted that the present invention does not limit the specific structure of the trigger response mechanism, as long as the first end of the guiding circuit can be electrically connected to the second electrode of the battery cell through the trigger response mechanism when a needle puncture occurs.

[0047] The following takes the first electrode as the positive electrode and the second electrode as the negative electrode as an example and combines three specific embodiments to introduce the technical solution of the present invention in detail.

[0048] Example 1

[0049] The following combines Figures 1 to 5 to introduce the technical solution of Embodiment 1 of the present invention in detail.

[0050] As Figures 1 to 5 shown, the battery of this embodiment includes a housing 1, a battery cell 2 installed in the housing 1, and a needle-puncture thermal runaway prevention device.

[0051] Among them, the needle-puncture thermal runaway prevention device includes a trigger response mechanism 3 and a guiding circuit 4. The trigger response mechanism 3 is installed between the housing 1 and the battery cell 2, and the guiding circuit 4 is installed outside the housing 1. The first end of the guiding circuit 4 is electrically connected to the trigger response mechanism 3, and the second end of the guiding circuit 4 is electrically connected to the positive electrode of the battery cell 2. The trigger response mechanism 3 is set to be able to electrically connect the first end of the guiding circuit 4 to the negative electrode of the battery cell 2 when being punctured by a needle, so that the guiding circuit 4 releases the energy of the battery cell 2 to avoid thermal runaway of the battery.

[0052] The trigger response mechanism 3 of this embodiment includes a first current collecting film 31, a second current collecting film 32, and an insulating layer 33 disposed between the first current collecting film 31 and the second current collecting film 32. The first current collecting film 31 is electrically connected to the negative electrode of the battery cell 2, the second current collecting film 32 is electrically connected to the first end of the guiding circuit 4, the second end of the guiding circuit 4 is electrically connected to the positive electrode of the battery cell 2, and both sides of the insulating layer 33 are respectively attached to the first current collecting film 31 and the second current collecting film 32.

[0053] When a needle puncture occurs, as Figure 2 shown, the needle 6 penetrates through the first current collecting film 31, the insulating layer 33, and the second current collecting film 32, so that the first current collecting film 31 and the second current collecting film 32 are electrically connected, thereby electrically connecting the first end of the guiding circuit 4 to the negative electrode of the battery cell 2.

[0054] It should be noted that in practical applications, those skilled in the art can also electrically connect the first current collecting film 31 to the positive electrode of the battery cell 2, and correspondingly, electrically connect the second end of the guiding circuit 4 to the negative electrode of the battery cell 2.

[0055] In addition, it should be noted that in practical applications, those skilled in the art can set the first current collector film 31 and / or the second current collector film 32 as an aluminum film or a copper film, etc., as long as the first current collector film 31 and the second current collector film 32 can achieve electrical conduction.

[0056] In addition, it should be noted that in practical applications, those skilled in the art can set the insulating layer 33 as a PP material or a PE material, etc., as long as the insulating layer 33 can achieve insulation.

[0057] In addition, it should be noted that the specific shape of the trigger response mechanism 3 is not limited in this embodiment. Those skilled in the art can flexibly set it according to the specific type of the battery. For example, as Figure 3 shown, if the battery is a cylindrical battery, the trigger response mechanism 3 is set as a cylindrical shape and tightly fits outside the battery cell 2, and is encapsulated into the case together with the battery cell 2. As Figure 4 and Figure 5 shown, if the battery is a blade battery or a soft-pack battery, the trigger response mechanism 3 is set as a flat shape, and two trigger response mechanisms 3 are provided and respectively pasted on both sides of the battery cell 2.

[0058] In addition, it should be noted that in practical applications, those skilled in the art can directly electrically connect the first end of the guiding circuit 4 to the trigger response mechanism 3, or alternatively, an insulating electrode can be installed on the case 1 of the battery, and the first end of the guiding circuit 4 is electrically connected to the trigger response mechanism 3 through the insulating electrode, etc. Such flexible adjustments and changes do not deviate from the principle and scope of the present invention and should be limited within the protection scope of the present invention.

[0059] Preferably, as Figures 3 to 5 shown, the acupuncture thermal runaway prevention device of the present invention further includes an insulating electrode 5, and the insulating electrode 5 is installed on the case 1. The first end of the guiding circuit 4 is electrically connected to the trigger response mechanism 3 through the insulating electrode 5.

[0060] Exemplarily, the insulating electrode 5 is installed at the end of the case 1, and the insulating electrode 5 is spaced apart from the positive electrode post 11 of the battery. One end of the insulating electrode 5 is inserted into the case 1 and electrically connected to the trigger response mechanism 3, and the other end of the insulating electrode 5 is electrically connected to the first end of the guiding circuit 4. That is to say, the insulating electrode 5 is equivalent to the external port of the trigger response mechanism 3.

[0061] It should be noted that if the case 1 of the battery is electrically connected to the negative electrode of the battery cell 2, an insulating structure (such as a rubber ring, etc.) needs to be provided between the insulating electrode 5 and the case 1. In addition, those skilled in the art can flexibly set the distance between the insulating electrode 5 and the positive electrode post 11 according to specific needs. For example, as Figure 3As shown, if the battery is a cylindrical battery, the conductive electrode 5 and the positive electrode column 11 are both installed on the top cover of the shell 1, then the distance between the conductive electrode 5 and the positive electrode column 11 is set to be more than 3mm, as shown in Figure 4 and Figure 5 As shown, if the battery is a blade battery or a soft pack battery, the distance between the conductive electrode 5 and the positive electrode column 11 is set to be greater than 5 mm.

[0062] Preferably, the elongation at break r1 of the insulating layer 33 is less than the elongation at break r2 of the separator of the battery cell 2. That is, r1<r2.

[0063] Among them, the elongation at break is the ratio of the elongated length after stretching to the length before stretching (usually expressed as a percentage).

[0064] By making the elongation at break of the insulating layer 33 smaller than the elongation at break of the separator of the battery cell 2, the battery can also be effectively protected from thermal runaway caused by needle puncture under non-metallic puncture conditions.

[0065] Further preferably, the elongation at break r1 of the insulating layer 33 is less than half of the elongation at break r2 of the separator of the battery cell 2. That is, r1<0.5×r2.

[0066] By making the elongation at break of the insulating layer 33 less than half of the elongation at break of the separator of the battery cell 2, the trigger response mechanism 3 can be triggered quickly under non-metallic puncture conditions, and the battery cell 2 can be punctured and short-circuited before the battery cell 2 is punctured, so that the power can be released quickly and the risk of thermal runaway can be avoided.

[0067] Preferably, the insulating layer 33 is in a stretched state.

[0068] By putting the insulating layer 33 in a stretched state, that is, pre-stretching the insulating layer 33 to a certain deformation, for example, the pre-deformation of the insulating layer 33 can be set to any value between 1% and 5%. Once pierced, the pierced hole will further expand under its own stress, so that the trigger response mechanism 3 can trigger the action more accurately and quickly.

[0069] Preferably, the thickness of the insulating layer 33 is greater than 3 microns.

[0070] By setting the thickness of the insulating layer 33 to be greater than 3 microns, false triggering can be effectively avoided.

[0071] Exemplarily, those skilled in the art may set the thickness of the insulating layer 33 to 4 micrometers, 5 micrometers, 8 micrometers, 10 micrometers or 15 micrometers, etc.

[0072] Preferably, the thickness d of the insulating layer 33 is less than half of the sum of the thickness d1 of the first collector film 31 and the thickness d2 of the second collector film 32. That is, d<0.5×(d1+d2)

[0073] By setting the thickness of the insulating layer 33 to be less than half of the sum of the thickness d1 of the first current collector film 31 and the thickness d2 of the second current collector film 32, the triggering sensitivity of the triggering response mechanism 3 can be effectively ensured.

[0074] Preferably, the resistance Ro of the diversion circuit 4 is greater than 1.2 times the resistance Rin of the battery and less than 3.5 times the resistance Rin of the battery. That is, 1.2×Rin<Ro<3.5×Rin.

[0075] With such a setting, it can not only ensure that the diversion circuit 4 has a fast enough discharge speed, but also ensure that the diversion circuit 4 releases enough energy, more effectively avoiding the occurrence of thermal runaway accidents caused by pinpricks.

[0076] Example 2

[0077] On the basis that other setting conditions of the above-mentioned first embodiment remain unchanged, the triggering response mechanism of this embodiment includes a current collector film and an insulating layer. The current collector film is electrically connected to the first end of the diversion circuit, the second end of the diversion circuit is electrically connected to the positive electrode of the battery cell, one side of the insulating layer is adhesively connected to the current collector film, and the other side of the insulating layer is adhesively connected to the inner wall of the housing, and the housing is connected to the negative electrode of the battery cell.

[0078] When a pinprick occurs, the acupuncture needle penetrates through the housing, insulating layer and current collector film of the battery, so that the current collector film and the housing are electrically connected, thereby making the first end of the diversion circuit electrically connected to the negative electrode of the battery cell.

[0079] It should be noted that in actual applications, those skilled in the art can also electrically connect the housing of the battery to the positive electrode of the battery cell, and correspondingly, electrically connect the second end of the diversion circuit to the negative electrode of the battery cell.

[0080] That is to say, compared with the triggering response mechanism in the above-mentioned first embodiment, the triggering response mechanism in this embodiment cancels the first current collector film and uses the housing of the battery to replace it.

[0081] Example 3

[0082] On the basis that other setting conditions of the above-mentioned first embodiment remain unchanged, the triggering response mechanism of this embodiment includes a current collector film and an insulating layer. The current collector film is electrically connected to the first end of the diversion circuit, the second end of the diversion circuit is electrically connected to the positive electrode of the battery cell, one side of the insulating layer is adhesively connected to the current collector film, and the other side of the insulating layer is adhesively connected to the negative electrode of the battery cell.

[0083] When a pinprick occurs, the acupuncture needle penetrates through the current collector film, insulating layer and negative electrode, so that the current collector film and the negative electrode are electrically connected, thereby making the first end of the diversion circuit electrically connected to the negative electrode of the battery cell.

[0084] It should be noted that in practical applications, those skilled in the art can also attach and connect the other side of the insulating layer to the positive electrode of the battery cell. Correspondingly, the second end of the guiding circuit is electrically connected to the negative electrode of the battery cell.

[0085] That is to say, compared with the trigger response mechanism in the first embodiment above, the trigger response mechanism in this embodiment cancels the first current collecting film and uses the negative electrode or the positive electrode of the battery cell to replace it.

[0086] Those skilled in the art can understand that although some of the embodiments described herein include certain features included in other embodiments rather than other features, the combination of the features of different embodiments means that it is within the scope of the present application and forms different embodiments. For example, in the claims of the present application, any one of the claimed embodiments can be used in any combination.

[0087] So far, the technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A device for preventing thermal runaway by needle puncture for a battery, the battery comprising a housing and a battery cell installed in the housing, characterized in that: The acupuncture thermal runaway prevention device comprises a trigger response mechanism and a drainage circuit, wherein the trigger response mechanism is installed between the housing and the battery cell, the drainage circuit is installed outside the housing, and a first end of the drainage circuit is electrically connected to the trigger response mechanism. The second end of the drain circuit is configured to be electrically connected to the first electrode of the battery cell, and the trigger response mechanism is configured to electrically connect the first end of the drain circuit to the second electrode of the battery cell when being punctured, so that the drain circuit releases the energy of the battery cell to avoid thermal runaway of the battery, wherein one of the first electrode and the second electrode is a positive electrode, and the other of the first electrode and the second electrode is a negative electrode.

2. The battery thermal runaway prevention device according to claim 1, characterized in that: The trigger response mechanism includes a first collector film, a second collector film, and an insulating layer disposed between the first collector film and the second collector film, the first collector film is electrically connected to the second electrode, the second collector film is electrically connected to the first end of the drainage circuit, and both sides of the insulating layer are respectively attached to the first collector film and the second collector film; Alternatively, the trigger response mechanism includes a collector film and an insulating layer, the collector film is electrically connected to the first end of the draining circuit, one side of the insulating layer is bonded to the collector film, the other side of the insulating layer is bonded to the inner wall of the shell, and the shell is electrically connected to the second electrode; Alternatively, the trigger response mechanism includes a collector film and an insulating layer, the collector film is electrically connected to the first end of the draining circuit, one side of the insulating layer is bonded to the collector film, and the other side of the insulating layer is bonded to the second electrode.

3. The battery thermal runaway prevention device according to claim 2, characterized in that: The elongation at break of the insulating layer is smaller than the elongation at break of the separator of the battery cell.

4. The battery thermal runaway prevention device according to claim 3, characterized in that: The elongation at break of the insulating layer is less than half of the elongation at break of the separator.

5. The battery thermal runaway prevention device according to claim 2, characterized in that: The thickness of the insulating layer is greater than 3 microns.

6. The battery thermal runaway prevention device according to claim 2, characterized in that: The thickness of the insulating layer is less than half of the sum of the thickness of the first collector film and the thickness of the second collector film.

7. The battery thermal runaway prevention device according to claim 2, characterized in that: The insulating layer is in a stretched state.

8. The battery puncture thermal runaway prevention device according to any one of claims 1 to 7, characterized in that: The acupuncture thermal runaway prevention device further comprises a drainage electrode, which is mounted on the housing, and the first end of the drainage circuit is electrically connected to the trigger response mechanism through the drainage electrode.

9. The battery puncture thermal runaway prevention device according to any one of claims 1 to 7, characterized in that: The resistance of the drain circuit is greater than 1.2 times the resistance of the battery and less than 3.5 times the resistance of the battery.

10. A battery, characterized in that: A battery puncture thermal runaway prevention device comprising any one of claims 1 to 9.

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