Method and system for triggering thermal runaway of batteries

Abstract

A method and system for triggering thermal runaway of batteries. The method comprises: perforating a first position of a housing of a target battery pack and a second position of a casing of a target battery cell respectively, so as to form a first through hole at the first position and a second through hole at the second position, wherein the target battery cell is located in the target battery pack, and the projection of the first through hole on the casing of the target battery cell intersects with the second through hole (S201); charging the target battery cell to a preset SOC (S202); and controlling a piercing portion of a piercing assembly to pierce into the target battery cell through the first through hole and the second through hole in sequence, with a cap portion of the piercing assembly covering the first through hole, wherein the piercing portion and the cap portion are connected to each other, and the cap portion is located at one end of the piercing portion in an axial direction (S203). The method can equivalently simulate an actual thermal runaway scenario of batteries.

Description

Battery thermal runaway triggering method and system CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is related to the Chinese Patent Application No. 202411389418.6 entitled “Battery thermal runaway triggering method and system” filed on September 30, 2024, which is incorporated by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of batteries, and in particular, to a battery thermal runaway triggering method and system. BACKGROUND

[0003] For thermal propagation test of a battery (or referred to as a battery pack), the main purpose is to simulate the phenomenon that the battery product occurs thermal runaway due to its own defects in the normal use process.

[0004] In some cases, the thermal runaway is triggered by setting a heating plate outside the battery. However, this case has the problem of being unable to equivalent to the actual battery thermal runaway scene. SUMMARY

[0005] In view of the above problems, the present application provides a battery thermal runaway triggering method and system, which can solve the problem of being unable to equivalent to the actual battery thermal runaway scene in some cases.

[0006] In a first aspect, the present application provides a battery thermal runaway triggering method, the method comprising:

[0007] Punching a first position of a shell of a target battery pack and a second position of a shell of a target cell to form a first perforation at the first position and a second perforation at the second position, wherein the target cell is located in the target battery pack, and a projection of the first perforation on the shell of the target cell intersects with the second perforation.

[0008] Charging the target cell to a preset SOC.

[0009] Controlling a puncture part of a puncture assembly to sequentially pass through the first perforation and the second perforation and penetrate into the inside of the target cell, and a cap part of the puncture assembly covers the first perforation, wherein the puncture part and the cap part are connected with each other, and the cap part is located at one end of the puncture part in an axial direction.

[0010] In the embodiments of the present application, the first position of the shell of the target battery pack and the second position of the shell of the target battery cell are respectively subjected to punching processing to form a first perforation at the first position and a second perforation at the second position, and after the target battery cell is charged to a preset SOC, the piercing part of the piercing assembly is controlled to sequentially pierce the first perforation and the second perforation into the interior of the target battery cell, so as to pierce the target component in the target battery cell, so that the interior of the target battery cell occurs partial short circuit, thereby triggering the target battery cell to occur thermal runaway from inside to outside, which can equivalently simulate the actual battery thermal runaway scene.

[0011] In some embodiments, in the case that a guide assembly is arranged between the first perforation and the second perforation, the piercing part of the piercing assembly sequentially pierces the first perforation and the second perforation into the interior of the target battery cell, comprising:

[0012] The piercing part is guided by the guide assembly to sequentially pierce the first perforation and the second perforation into the interior of the target battery cell along the extension direction of the guide assembly.

[0013] In the embodiments of the present application, the piercing part is guided by the guide assembly to sequentially pierce the first perforation and the second perforation into the interior of the target battery cell along the extension direction of the guide assembly, which is beneficial to more accurately pierce the target component in the target battery cell, so that the interior of the target battery cell occurs more accurate partial short circuit, thereby triggering the target battery cell to occur thermal runaway.

[0014] In some embodiments, the first position of the shell of the target battery pack and the second position of the shell of the target battery cell are respectively subjected to punching processing to form a first perforation at the first position and a second perforation at the second position, comprising:

[0015] The first position of the top cover of the target battery pack and the second position of the top cover of the target battery cell are respectively subjected to punching processing to form a first perforation at the first position and a second perforation at the second position.

[0016] In some embodiments, the projection of the first perforation on the shell of the target battery cell can cover the second perforation, so that the piercing part of the piercing assembly can sequentially pierce the first perforation and the second perforation according to the straight line distance and directly pierce into the interior of the target battery cell.

[0017] In some embodiments, the piercing part of the piercing assembly sequentially pierces the first perforation and the second perforation into the interior of the target battery cell, comprising:

[0018] The cap part of the piercing assembly is grabbed by the grabbing assembly;

[0019] The grabbing assembly is moved by the moving assembly towards the direction close to the shell of the target battery cell to drive the piercing part of the piercing assembly to sequentially pierce the first perforation and the second perforation into the interior of the target battery cell.

[0020] In the embodiments of the present application, the cap part of the puncture assembly is grabbed by the grabbing assembly, and the grabbing assembly is moved by the moving assembly towards the direction close to the shell of the target battery cell, so that the puncture part of the puncture assembly sequentially passes through the first and second puncture holes and penetrates into the interior of the target battery cell, thereby realizing the automatic triggering of the thermal runaway of the target battery cell and facilitating the protection of the detection personnel.

[0021] In some embodiments, moving the grabbing assembly by the moving assembly towards the direction close to the shell of the target battery cell comprises:

[0022] The moving part in the moving assembly is driven by the driving part in the moving assembly to move along the first preset direction at a first moving speed, so as to drive the grabbing assembly to move towards the direction close to the shell of the target battery cell.

[0023] In some embodiments, the first moving speed is 1mm / s-8mm / s.

[0024] In some embodiments, the method further comprises:

[0025] In the case of thermal runaway of the target battery cell, the cap part of the puncture assembly is released by the grabbing assembly;

[0026] The grabbing assembly is moved by the moving assembly towards the direction away from the shell of the target battery pack.

[0027] In the embodiments of the present application, in the case of thermal runaway of the target battery cell, the cap part of the puncture assembly is released by the grabbing assembly, and the grabbing assembly is moved by the moving assembly towards the direction away from the shell of the target battery pack, thereby preparing for the next battery cell thermal runaway triggering process and facilitating the improvement of the efficiency of battery cell thermal runaway triggering.

[0028] In some embodiments, moving the grabbing assembly by the moving assembly towards the direction away from the shell of the target battery pack comprises:

[0029] The moving part in the moving assembly is driven by the driving part in the moving assembly to move along the second preset direction at a second moving speed, so as to drive the grabbing assembly to move towards the direction away from the shell of the target battery pack.

[0030] In some embodiments, the second moving speed is 3cm / s-5cm / s.

[0031] In some embodiments, before the sealing and punching device respectively punches the first position in the shell of the target battery pack and the second position in the shell of the target battery cell, the method further comprises:

[0032] The target battery cell is fully discharged to facilitate the protection of the target battery cell in the target battery pack during the punching process of the target battery cell.

[0033] In a second aspect, the present application provides a battery thermal runaway triggering system, the system comprising:

[0034] The charging and discharging device is configured to charge a target battery cell in a target battery pack to a preset SOC; wherein a first position of a shell of the target battery pack is provided with a first perforation, and a second position of a shell of the target battery cell is provided with a second perforation; a projection of the first perforation on the shell of the target battery cell intersects with the second perforation.

[0035] The liftable grabbing device is configured to control a puncture part of the puncture assembly to sequentially puncture into the interior of the target battery cell through the first perforation and the second perforation, and a cap part of the puncture assembly covers the first perforation; wherein the puncture part and the cap part are connected with each other, and the cap part is located at one end of the puncture part in an axial direction.

[0036] In some embodiments, the puncture assembly further comprises a first sealing member arranged at one side of the cap part; wherein in the case that the cap part covers the first perforation, the first sealing member is located between the cap part and the first perforation.

[0037] In the embodiments of the present application, by arranging the first sealing member, the cap part of the puncture assembly can sealably cover the first perforation, which can prevent oxygen from entering the target battery pack through the first perforation during thermal runaway of the target battery cell, and also prevent thermal runaway gas from being sprayed out of the first perforation, so as to change the failure path of thermal runaway, thereby more effectively simulating the battery thermal runaway scenario.

[0038] In some embodiments, the length of the puncture part is greater than the vertical distance between the shell of the target battery pack and the shell of the target battery cell.

[0039] In some embodiments, the system further comprises a guide assembly; wherein the guide assembly is arranged between the first perforation and the second perforation, and is configured to guide the puncture part to sequentially puncture into the interior of the target battery cell through the first perforation and the second perforation along the extension direction of the guide assembly.

[0040] In some embodiments, a first position of a top cover of the target battery pack is provided with the first perforation, and a second position of a top cover of the target battery cell is provided with the second perforation.

[0041] In some embodiments, the projection of the first perforation on the shell of the target battery cell can cover the second perforation.

[0042] In some embodiments, the system further comprises a second sealing member, wherein the second sealing member is arranged between the guide assembly and the second perforation.

[0043] In some embodiments, the liftable grabbing device comprises:

[0044] The grabbing assembly is used for grabbing the cap part of the puncturing assembly;

[0045] The moving assembly connected with the grabbing assembly is used for moving the grabbing assembly towards the shell of the target battery cell, so that the puncturing part of the puncturing assembly sequentially passes through the first and second through holes and penetrates into the inside of the target battery cell.

[0046] In some embodiments, the moving assembly comprises a driving member and a moving member, wherein the grabbing assembly is connected with the moving member;

[0047] The driving member is used for driving the moving member to move along a first preset direction at a first moving speed, so that the grabbing assembly moves towards the shell of the target battery cell.

[0048] In some embodiments, the grabbing assembly is further used for releasing the cap part of the puncturing assembly in the case that the target battery cell occurs thermal runaway;

[0049] The moving assembly is further used for moving the grabbing assembly away from the shell of the target battery pack.

[0050] In some embodiments, the driving member is further used for driving the moving member in the moving assembly to move along a second preset direction at a second moving speed, so that the grabbing assembly moves away from the shell of the target battery pack.

[0051] In some embodiments, the charging and discharging device is further used for full discharging the target battery cell.

[0052] In some embodiments, the diameter of the puncturing part is 0.5mm-1mm.

[0053] In some embodiments, the material of the puncturing part is any one of the following: aluminum alloy, copper alloy, tungsten steel alloy.

[0054] In some embodiments, the diameter of the first through hole is 3mm-4mm; and / or,

[0055] The diameter of the second through hole is 1mm-2mm.

[0056] In some embodiments, the shell of the target battery cell and the shells of the battery cells adjacent to the target battery cell in the target battery pack are provided with temperature acquisition assemblies;

[0057] The temperature acquisition assembly is used for acquiring the temperature of the corresponding battery cell.

[0058] The above description is only a summary of the technical solutions of the present application. In order to more clearly understand the technical means of the present application, the following embodiments of the present application can be implemented according to the content of the description, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0059] Various other advantages and benefits will become apparent to those of ordinary skill in the art, upon reading the following detailed description of the preferred embodiment. The detailed description is made with reference to the accompanying drawings.

[0060] Fig. 1 is a structural schematic diagram of a battery thermal runaway triggering system according to some embodiments of the present application;

[0061] Fig. 2 is a flowchart of a battery thermal runaway triggering method according to some embodiments of the present application;

[0062] Fig. 3 is a structural schematic diagram of a piercing assembly according to some embodiments of the present application;

[0063] Fig. 4 is a structural schematic diagram of a piercing assembly according to some other embodiments of the present application;

[0064] Fig. 5 is a schematic diagram of a guide assembly according to some embodiments of the present application;

[0065] Fig. 6 is a structural schematic diagram of a battery thermal runaway triggering system according to some other embodiments of the present application;

[0066] Fig. 7 is a flowchart of a battery thermal runaway triggering method according to some other embodiments of the present application;

[0067] Fig. 8 is a structural schematic diagram of a battery thermal runaway triggering system according to some other embodiments of the present application;

[0068] Fig. 9 is a flowchart of a battery thermal runaway triggering method according to some other embodiments of the present application;

[0069] Fig. 10 is a flowchart of a battery thermal runaway triggering method according to some other embodiments of the present application. DETAILED DESCRIPTION

[0070] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0071] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing the embodiments of the present application only, and is not intended to limit the present application; the terms "comprise", "comprises" and any variations thereof in the specification and claims of the present application and the above description of the drawings are intended to cover not exclusively include.

[0072] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more (including two), unless otherwise explicitly limited therein.

[0073] The battery thermal runaway triggering method and system provided by the embodiments of the present application can be applied to the application scenario of battery thermal runaway diffusion test (or called battery thermal runaway detection); of course, it can also be applied to other application scenarios.

[0074] In some cases, the thermal runaway is triggered by setting a heating plate outside the battery. Among them, the external heating plate method needs to deform the battery shell first, and then trigger the thermal runaway of the battery cell inside the battery, that is, the battery failure is from outside to inside. Since the actual battery thermal runaway scenario is usually caused by internal short circuit of the battery cell, etc. to trigger thermal runaway (that is, the failure is from inside to outside), therefore, in this case, there is a problem that it cannot be equivalent to the actual battery thermal runaway scenario. In addition, the external heating plate method usually needs to be deeply modified to the battery, and there is a problem of complex operation.

[0075] In order to solve the problems in the above cases, the embodiments of the present application propose to respectively punch the shell of the target battery pack and the shell of the target battery cell to form a first perforation in the shell of the battery pack and a second perforation in the shell of the target battery cell, and after charging the target battery cell to a preset state of charge (SOC), the puncture part of the puncture assembly is controlled to pass through the first perforation and the second perforation in turn to penetrate into the inside of the target battery cell. The way is to pierce the target component in the target battery cell, so that the internal short circuit of the target battery cell occurs, thereby triggering the thermal runaway of the target battery cell from inside to outside, which can be equivalent to simulate the actual battery thermal runaway scenario.

[0076] For ease of understanding, the related content of the battery thermal runaway triggering system is first introduced and explained in the embodiments of the present application.

[0077] For ease of understanding, the related content of the battery thermal runaway triggering system is first introduced and explained in the embodiments of the present application.

[0078] In some embodiments, FIG. 1 is a structural schematic diagram of a battery thermal runaway triggering system provided by some embodiments of the present application, as shown in FIG. 1, the battery thermal runaway triggering system of the embodiments of the present application can include: a charge and discharge device 11 and a liftable grabbing device 12.

[0079] The charging and discharging device 11 in the embodiment of the present application can be connected with the target battery pack (or referred to as a trigger battery pack) 10, so as to perform charging and discharging processing on a target battery cell (or referred to as a trigger battery cell) at a preset position in the target battery pack 10. The target battery pack 10 can include a plurality of battery cells C, and the target battery cell can be one of the plurality of battery cells C. It should be understood that the target battery pack 10 can include, but is not limited to, a shell 10H of the target battery pack 10 and a plurality of battery cells C located in the shell 10H of the target battery pack 10. The shell 10H of the target battery pack 10 can include, but is not limited to, a top cover 10H1 of the target battery pack 10 and a box body 10H2. For example, in FIG. 1, a plurality of battery cells C are located in the box body 10H2 of the target battery pack 10.

[0080] It should be noted that the first position in the shell of the target battery pack in the embodiment of the present application can be provided with a first perforation, and the second position in the shell of the target battery cell can be provided with a second perforation, and the projection of the first perforation on the shell of the target battery cell can intersect with the second perforation, so that the puncture part of the puncture assembly 13 can directly penetrate into the interior of the target battery cell through the first perforation and the second perforation.

[0081] For example, the liftable grabbing device 12 can control the puncture part of the puncture assembly 13 to penetrate into the interior of the target battery cell through the first perforation and the second perforation in sequence, so that the interior of the target battery cell is partially short-circuited, thereby triggering the target battery cell to occur thermal runaway.

[0082] Of course, the battery thermal runaway triggering system in the embodiment of the present application can also include other devices, such as a punching device.

[0083] In some embodiments, FIG. 2 is a flow diagram of a battery thermal runaway triggering method provided by some embodiments of the present application. As shown in FIG. 2, the battery thermal runaway triggering method in the embodiment of the present application can include the following steps:

[0084] Step S201, respectively punching the first position of the shell of the target battery pack and the second position of the shell of the target battery cell to form a first perforation at the first position and a second perforation at the second position; wherein the target battery cell is located in the target battery pack, and the projection of the first perforation on the shell of the target battery cell intersects with the second perforation.

[0085] In this step, on the one hand, the first position of the shell of the target battery pack can be punched to form a first perforation at the first position of the shell of the target battery pack, so that the piercing part 13a of the piercing assembly 13 can directly extend into the interior of the target battery pack through the first perforation. On the other hand, the second position of the shell of the target battery cell in the target battery pack can be punched to form a second perforation at the second position of the shell of the target battery cell, so that the piercing part 13a of the piercing assembly 13 can directly extend into the interior of the target battery cell through the second perforation, which can reduce the damage and interference to the target battery cell in the process of directly piercing the target battery cell (without pre-punching), and is beneficial to realize the local piercing micro-short circuit of the target battery cell, so that the actual battery thermal runaway working condition can be more equivalent.

[0086] The projection of the first perforation on the shell of the target battery cell intersects with the second perforation, so that the piercing part 13a of the piercing assembly 13 can directly pierce into the interior of the target battery cell through the first perforation and the second perforation in sequence.

[0087] For example, the projection of the first perforation on the shell of the target battery cell can cover the second perforation (cover all the second perforations, that is, completely cover the second perforation), so that the piercing part 13a of the piercing assembly 13 can directly pierce into the interior of the target battery cell through the first perforation and the second perforation in sequence according to the straight line distance.

[0088] For another example, the projection of the first perforation on the shell of the target battery cell can be located in the second perforation, so that the piercing part 13a of the piercing assembly 13 can more smoothly pierce into the interior of the target battery cell through the first perforation and the second perforation in sequence.

[0089] For another example, the projection of the first perforation on the shell of the target battery cell can partially overlap with the second perforation.

[0090] In a possible implementation, the first position of the top cover of the target battery pack and the second position of the top cover of the target battery cell can be punched respectively to form a first perforation at the first position and a second perforation at the second position.

[0091] In this implementation, when the target battery pack is placed in the forward direction, the first position of the top cover of the target battery pack and the second position of the top cover of the target battery cell are punched respectively to form a first perforation at the first position and a second perforation at the second position, so that the piercing part 13a of the piercing assembly 13 can directly pierce into the interior of the target battery cell through the first perforation and the second perforation in sequence, so as to trigger the thermal runaway of the target battery cell from the inside to the outside.

[0092] In another possible implementation, the first position of the first target box wall in the box of the target battery pack and the second position of the second target box wall in the box of the target battery cell can be respectively punched to form a first perforation at the first position and a second perforation at the second position. For example, the first target box wall can be a box wall (or referred to as a bottom plate of the target battery pack) in the box of the target battery pack opposite to the top cover, and the second target box wall can be a box wall (or referred to as a bottom plate of the target battery cell) in the box of the target battery cell opposite to the top cover.

[0093] In the present implementation, when the target battery pack is placed upside down, the first position of the first target box wall (or referred to as a bottom plate of the target battery pack) in the box of the target battery pack and the second position of the second target box wall (or referred to as a bottom plate of the target battery cell) in the box of the target battery cell can be respectively punched to form a first perforation at the first position and a second perforation at the second position, so that the puncture part 13a of the puncture assembly 13 can directly penetrate into the inside of the target battery cell through the first perforation and the second perforation in sequence to trigger the thermal runaway of the target battery cell from inside to outside.

[0094] Of course, in the present application, other positions in the shell of the target battery pack and other positions in the shell of the target battery cell can also be respectively punched.

[0095] For ease of understanding, the related content of the punching processing mode in the following embodiments of the present application is exemplarily introduced and described.

[0096] In a possible implementation, the first position of the shell of the target battery pack and the second position of the shell of the target battery cell can be respectively sealed and punched by a punching device to form a first perforation at the first position and a second perforation at the second position. The punching device can include but is not limited to any one of the following: a pneumatic punch (or referred to as a gas gun), a laser punch, an ultrasonic punch, an electric drill, a hydraulic punch.

[0097] For example, a specially designed hollow sealing nail can be implanted into the shell of the target battery cell by a gas gun impact to punch a perforation.

[0098] In another possible implementation, the first position of the shell of the target battery pack and the second position of the shell of the target battery cell can be respectively sealed and punched by chemical etching, electric spark punching or mechanical punching to form a first perforation at the first position and a second perforation at the second position.

[0099] Of course, the first position of the shell of the target battery pack and the second position of the shell of the target battery cell can also be respectively sealed and punched by other ways.

[0100] It should be understood that the order of the punching process on the shell of the target battery pack and the punching process on the shell of the target battery cell is not limited in the embodiments of the present application.

[0101] Step S202, charging the target battery cell to a preset SOC.

[0102] In this step, the target battery cell is charged to a preset SOC, so that in the subsequent case that the puncture part 13a of the puncture assembly 13 successively passes through the first and second perforations to pierce into the interior of the target battery cell, the target battery cell can be quickly triggered to occur thermal runaway.

[0103] In some embodiments, the preset SOC can include but is not limited to a preset trigger SOC, and the target battery cell can be fully charged to the preset trigger SOC, so that in the subsequent case that the puncture part 13a of the puncture assembly 13 successively passes through the first and second perforations to pierce into the interior of the target battery cell, the target battery cell can be more quickly triggered to occur thermal runaway. For example, the preset trigger SOC can include but is not limited to 90% to 100%.

[0104] In some embodiments, the preset SOC can include but is not limited to a preset non-trigger SOC, and the target battery cell can be charged to the preset SOC, so that in the subsequent case that the puncture part 13a of the puncture assembly 13 successively passes through the first and second perforations to pierce into the interior of the target battery cell, the target battery cell can be quickly triggered to occur thermal runaway. For example, the preset non-trigger SOC can be less than the preset trigger SOC.

[0105] For example, the target battery cell can be charged to the preset SOC according to a first preset C-rate, where the first preset C-rate can include but is not limited to 0.33C-rate (C) to 1C. For example, the first preset C-rate can be 1C.

[0106] For another example, the target battery cell can be charged to the preset SOC according to a preset variable C-rate.

[0107] In one possible implementation, the target battery cell can be charged to the preset SOC by a charging and discharging device.

[0108] In another possible implementation, the target battery cell can be charged to the preset SOC by an intelligent charging device or a special charger.

[0109] Step S203, controlling the puncture part of the puncture assembly to successively pass through the first and second perforations to pierce into the interior of the target battery cell, and the cap part of the puncture assembly covers the first perforation; wherein the puncture part and the cap part are connected to each other, and the cap part is located at one end of the axial direction of the puncture part.

[0110] In some embodiments, for the convenience of understanding, the application embodiments exemplarily introduce the related content of the puncture assembly 13.

[0111] FIG. 3 is a structural schematic diagram of a puncture assembly provided by some embodiments of the application. As shown in FIG. 3, the puncture assembly 13 can include a puncture part 13a and a cap part 13b. Wherein, the puncture part 13a and the cap part 13b are connected with each other, and the cap part 13b is located at one end of the puncture part 13a in the axial direction, so that in the case that the puncture part 13a of the puncture assembly 13 sequentially passes through the first perforation and the second perforation to pierce into the inside of the target battery cell, the cap part 13b of the puncture assembly 13 can cover the first perforation; wherein the diameter of the cap part 13b can be greater than the diameter of the first perforation.

[0112] Exemplarily, the diameter of the cap part can be 5 millimeters (mm) to 6 mm. For example, in the case that the diameter of the first perforation is 3 mm, the diameter of the cap part can be 5 mm.

[0113] In some embodiments, the length of the puncture part 13a of the application embodiments can be greater than the vertical distance between the shell of the target battery pack and the shell of the target battery cell, so that the puncture part 13a of the puncture assembly 13 can pierce into the inside of the target battery cell after passing through the first perforation and the second perforation, so as to pierce the target component (for example, the diaphragm, or the diaphragm and the positive electrode sheet, or the diaphragm and the negative electrode sheet, or the diaphragm, the positive electrode sheet and the negative electrode sheet, etc.) in the target battery cell. For example, the length of the puncture part 13a can be the sum of the vertical distance between the shell of the target battery pack and the shell of the target battery cell and a preset length, wherein the preset length can be 3 centimeters (cm) to 5 cm.

[0114] Exemplarily, the other end of the puncture part 13a away from the cap part 13b can be a sharp end, so that the puncture part 13a can pierce the target component in the target battery cell.

[0115] The material of the puncture part in the application embodiments can be a special metal with high hardness and corrosion resistance, so that the puncture part has a certain rigidity, so as to be able to pierce the target component in the target battery cell.

[0116] Exemplarily, the material of the puncture part in the application embodiments includes but is not limited to any one of the following: aluminum alloy, copper alloy, tungsten steel alloy.

[0117] Exemplarily, the diameter of the puncture part 13a in the application embodiments can be 0.5 mm to 1 mm, so as to be less destructive to the target battery cell on the basis of piercing the target component in the target battery cell, and the target battery cell will not be deformed.

[0118] The diameters of the first and second perforations in the embodiments of the present application can be greater than or equal to the diameter of the puncture portion 13a, so that the puncture portion 13a can pass through the first and second perforations.

[0119] It should be noted that the sizes of the puncture portion 13a and the cap portion 13b of the puncture assembly 13 involved in the embodiments of the present application are exemplary values, which can be designed according to the sizes of different battery packs.

[0120] In this step, the puncture portion 13a of the puncture assembly 13 can be controlled to pass through the first and second perforations in sequence and directly pierce into the inside of the target battery cell to pierce the target component in the target battery cell, so that a local short circuit occurs in the inside of the target battery cell at the moment when the puncture portion 13a pierces the target component, to cause a rapid temperature rise of the target battery cell and trigger a thermal runaway of the target battery cell from the inside to the outside (verified that the instantaneous temperature rise rate dT / dt of the target battery cell through the embodiments of the present application is ≥1 degree Celsius per second (℃ / s) and the duration is more than 3 seconds (s)).

[0121] In summary, compared with the external heating plate method in the above-mentioned situation, in the embodiments of the present application, the first position of the shell of the target battery pack and the second position of the shell of the target battery cell are respectively perforated to form a first perforation at the first position and a second perforation at the second position, and after the target battery cell is charged to a preset SOC, the puncture portion of the puncture assembly is controlled to pass through the first and second perforations in sequence to pierce into the inside of the target battery cell, so that a local short circuit occurs in the inside of the target battery cell, thereby triggering a thermal runaway of the target battery cell from the inside to the outside, which can simulate an actual battery thermal runaway scenario.

[0122] In some embodiments, FIG. 4 is a structural schematic diagram of a puncture assembly provided by another embodiment of the present application. Considering that in an actual battery thermal runaway scenario, thermal runaway gas and the like will be discharged through the explosion-proof valve of the battery pack, in order to better simulate the battery thermal runaway scenario, the puncture assembly 13 of the embodiments of the present application can further include a first sealing member 13c arranged on one side of the cap portion 13b. Wherein, when the cap portion 13b covers the first perforation, the first sealing member 13c is located between the cap portion 13b and the first perforation, so that the cap portion 13b can sealingly cover the first perforation.

[0123] For example, the first sealing member 13c can be a rubber plug.

[0124] In the embodiments of the present application, by means of the first sealing member, the cap part 13b of the puncture assembly 13 can sealingly cover the first puncture hole, so as to prevent oxygen from entering the target battery pack through the first puncture hole during thermal runaway of the target battery cell, and also prevent thermal runaway gas from being sprayed out of the first puncture hole, so as to change the failure path of thermal runaway, that is, during thermal runaway of the target battery cell in the target battery pack, the thermal runaway gas and the like can still be discharged through the explosion-proof valve of the target battery pack, so as to more effectively simulate the battery thermal runaway scene.

[0125] In some embodiments, in order to control the direction of the puncture part of the puncture assembly penetrating into the target battery pack, FIG. 5 shows a schematic diagram of the setting of the guide assembly according to some embodiments of the present application. As shown in FIG. 5, the battery thermal runaway triggering system according to the embodiments of the present application can further include a guide assembly 14, wherein the guide assembly 14 can be arranged between the first puncture hole P1 and the second puncture hole P2.

[0126] Correspondingly, in the case that the guide assembly 14 is arranged between the first puncture hole P1 and the second puncture hole P2, the above step S203 can include: guiding the puncture part to penetrate into the interior of the target battery cell through the first puncture hole and the second puncture hole in sequence along the extension direction of the guide assembly 14 by means of the guide assembly 14.

[0127] In the embodiments of the present application, by means of the guide assembly 14 guiding the puncture part to penetrate into the interior of the target battery cell through the first puncture hole P1 and the second puncture hole P2 in sequence along the extension direction of the guide assembly, it is beneficial to more accurately puncture the target component in the target battery cell, so as to cause more accurate local short circuit in the interior of the target battery cell, thereby triggering thermal runaway of the target battery cell.

[0128] In a possible implementation manner, the guide assembly 14 can be a hollow tubular structure (as an example shown in FIG. 5), and the inner diameter of the guide assembly 14 can be greater than or equal to the diameter of the puncture part, so as to facilitate the puncture part to penetrate into the interior of the target battery cell through the first puncture hole and the second puncture hole in sequence along the extension direction of the guide assembly 14. For example, the guide assembly 14 can adopt a guide pipe structure.

[0129] For example, the diameter of the first puncture hole can be greater than or equal to the outer diameter of the guide assembly 14, so as to facilitate the guide assembly 14 to pass through the first puncture hole, and so as to facilitate the guide assembly 14 to be arranged between the first puncture hole and the second puncture hole. It should be understood that one end of the guide assembly 14 can be fixed to the first puncture hole, and the other end of the guide assembly 14 can be connected with the second puncture hole, wherein the inner diameter of the guide assembly 14 can be greater than or equal to the diameter of the second puncture hole, so as to facilitate the other end of the guide assembly 14 to be connected with the second puncture hole.

[0130] Exemplarily, the first perforation can have a diameter of 3mm-4mm; and / or, the second perforation can have a diameter of 1mm-2mm.

[0131] For example, in the case where the diameter of the puncture part is 0.5mm, the diameter of the first perforation can be 3mm, and the diameter of the second perforation can be 1mm. Correspondingly, the outer diameter of the guide assembly can be 3mm, and the inner diameter can be 1.5mm.

[0132] It should be noted that, in the case where the guide assembly is not arranged between the first perforation and the second perforation, the diameters of the first perforation and the second perforation can be slightly larger than the diameter of the puncture part 13a, and the gap between the puncture part 13a and each perforation can be small on the basis that the puncture part 13a passes through the first perforation and the second perforation.

[0133] In another possible implementation, the guide assembly 14 can be a semi-hollow tubular structure, so that the puncture part can sequentially penetrate into the interior of the target battery cell along the extension direction of the guide assembly 14 through the first perforation and the second perforation.

[0134] In some embodiments, in order to better simulate the battery thermal runaway scenario, the battery thermal runaway triggering system can further include a second sealing member (not shown in FIG. 5); wherein the second sealing member is arranged between the guide assembly 14 and the second perforation P2, so that the guide assembly 14 can be in sealed connection with the second perforation P2, and the thermal runaway gas and the like can be prevented from being sprayed out of the second perforation, so as to change the failure path of thermal runaway, thereby more effectively simulating the battery thermal runaway scenario.

[0135] In a possible implementation, the second sealing member can include but is not limited to a sealing gasket or a sealing washer.

[0136] In another possible implementation, the second sealing member can be a sealing member obtained by sealing the guide assembly and the second perforation through a sealing device. The sealing device can include but is not limited to any one of the following: a glue filling machine, a sealing glue nail vacuum sealing machine, and a sealing glue gun.

[0137] Exemplarily, AB glue or other glue with high strength can be arranged between the guide assembly and the second perforation by the sealing device to form the second sealing member.

[0138] In some embodiments, FIG. 6 is a structural schematic diagram of a battery thermal runaway triggering system provided by another embodiment of the present application. As shown in FIG. 6, the liftable grabbing device 12 can include a grabbing assembly 121 and a moving assembly 122 connected with the grabbing assembly 121. The grabbing assembly 121 can be used to grab the puncture assembly 13, and the moving assembly 122 can be used to drive the grabbing assembly 121 to move.

[0139] FIG. 7 is a flowchart of a battery thermal runaway triggering method according to some embodiments of the present application. As shown in FIG. 7, step S203 can include the following steps:

[0140] Step S203A, the cap part of the puncture assembly is grabbed by the grabbing assembly.

[0141] In this step, the cap part of the puncture assembly 13 can be grabbed by the grabbing assembly 121, so that the puncture assembly can be quickly and accurately grabbed.

[0142] For example, the grabbing assembly 121 can include but is not limited to a grabbing clamp and a crossbeam for fixing the grabbing clamp. The crossbeam can be connected with the moving assembly 122, so that the grabbing clamp can be driven to move up and down and / or left and right by the moving assembly 122.

[0143] Of course, the grabbing assembly 121 can also be implemented by other structures that can realize the moving and grabbing function.

[0144] Step S203B, the grabbing assembly is moved by the moving assembly towards the direction close to the shell of the target battery cell, so that the puncture part of the puncture assembly can sequentially pass through the first and second perforations and penetrate into the interior of the target battery cell.

[0145] In this step, the grabbing assembly 121 is moved by the moving assembly 122 towards the direction close to the shell of the target battery cell, so that the puncture part of the puncture assembly can sequentially pass through the first and second perforations and penetrate into the interior of the target battery cell, so as to puncture the target component in the target battery cell, cause the internal short circuit of the target battery cell, and trigger the thermal runaway of the target battery cell from inside to outside.

[0146] In some embodiments, FIG. 8 is a structural diagram of a battery thermal runaway triggering system according to some embodiments of the present application. As shown in FIG. 8, the moving assembly 122 can include a driving member 122a and a moving member 122b. The grabbing assembly 121 can be connected with the moving member 122b, so that the grabbing assembly 121 can be moved by the moving member 122b.

[0147] In the embodiments of the present application, the moving member 122b in the moving assembly 122 is driven by the driving member 122a in the moving assembly 122 to move along the first preset direction D1 at a first moving speed, so that the grabbing assembly 121 can be moved towards the direction close to the shell of the target battery cell, and the puncture part of the puncture assembly can sequentially pass through the first and second perforations and penetrate into the interior of the target battery cell.

[0148] For example, the driving member 122a can include, but is not limited to, a motor driving member or a hydraulic driving member, and the moving member 122b can include, but is not limited to, a movable track connected with the driving member 122a, so as to move under the driving of the driving member 122a. It should be understood that the grabbing assembly 121 can be fixedly connected with the moving member 122b, so as to be moved together with the moving member 122b.

[0149] For example, the first moving speed can include, but is not limited to, 1 millimeter / second (mm / s) to 8 mm / s.

[0150] Of course, the grabbing assembly can also be moved towards the direction close to the shell of the target battery cell by other ways.

[0151] In summary, in the embodiments of the present application, the cap part of the puncturing assembly is grabbed by the grabbing assembly, and the grabbing assembly is moved towards the direction close to the shell of the target battery cell by the moving assembly, so as to drive the puncturing part of the puncturing assembly to sequentially pierce into the inside of the target battery cell through the first and second perforations, thereby realizing the automatic triggering of the thermal runaway of the target battery cell, and facilitating the protection of the detection personnel.

[0152] In some embodiments, FIG. 9 is a flow diagram of a battery thermal runaway triggering method provided by another embodiment of the present application. As shown in FIG. 9, the battery thermal runaway triggering method of the embodiment of the present application can further include the following steps:

[0153] In step S204, the cap part of the puncturing assembly is released by the grabbing assembly in the case of thermal runaway of the target battery cell.

[0154] In this step, in the case of thermal runaway of the target battery cell, the grabbing assembly 121 can release the cap part of the puncturing assembly, so as not to move the puncturing part of the puncturing assembly under the driving of the moving assembly 122 in the subsequent process.

[0155] In step S205, the grabbing assembly is moved away from the shell of the target battery pack by the moving assembly.

[0156] In this step, the grabbing assembly 121 is moved away from the shell of the target battery pack by the moving assembly 122, so as to move the grabbing assembly 121 to the preset initial position.

[0157] For example, the moving member 122b in the moving assembly 122 is driven by the driving member 122a in the moving assembly 122 to move along a second preset direction at a second moving speed, so as to move the grabbing assembly 121 away from the shell of the target battery pack, so as to prepare for the next thermal runaway triggering process of the battery cell. The second preset direction can be opposite to the first preset direction.

[0158] For example, the second moving speed is 3 cm / s to 5 cm / s.

[0159] To sum up, in the case of thermal runaway of the target battery cell, the cap part of the puncture assembly is released by the grabbing assembly, and the grabbing assembly is moved away from the target battery pack shell by the moving assembly. This can prepare for the next thermal runaway trigger process of the battery cell, and improve the efficiency of the thermal runaway trigger of the battery cell.

[0160] In some embodiments, considering that there may be certain safety hazards in the process of punching the target battery cell when the target battery cell has a large amount of electricity, the target battery cell can be fully discharged before step S201 in the embodiment of the application, so as to facilitate the protection of the target battery cell in the target battery pack during the punching process of the target battery cell.

[0161] For example, the target battery cell in the target battery pack can be fully discharged at a second preset rate, wherein the second preset rate can include but is not limited to 0.33C to 1C. For example, the second preset rate can be 0.33C.

[0162] In a possible implementation, the target battery cell in the target battery pack can be fully discharged by the charging and discharging device.

[0163] In another possible implementation, the target battery cell in the target battery pack can be fully discharged by bulb discharge, electrolyte discharge, or high-power resistance discharge.

[0164] Of course, the target battery cell in the target battery pack can also be fully discharged in other ways.

[0165] In some embodiments, in order to facilitate subsequent research and analysis of the process of thermal runaway of the target battery cell in the target battery pack, the target battery cell in the target battery pack and the shells of each battery cell adjacent to the target battery cell in the target battery pack can be provided with corresponding temperature acquisition assemblies; wherein the temperature acquisition assembly can be used to acquire the temperature of the corresponding battery cell.

[0166] For example, the temperature acquisition assembly can include but is not limited to a temperature sensor or a thermocouple. It should be understood that the temperature acquisition assembly in the embodiment of the application can record the temperature of the corresponding battery cell in real time, or can record the temperature of the corresponding battery cell every preset time interval.

[0167] For example, the top cover of the target battery cell in the target battery pack and the top cover of each battery cell adjacent to the target battery cell in the target battery pack can be provided with corresponding temperature acquisition assemblies, so that the temperature at the corresponding position can be acquired respectively.

[0168] It should be noted that the temperature collection assembly in the embodiments of the present application can also be arranged at other positions (such as the side wall or bottom plate of the battery cell, etc.) corresponding to the battery cell, and the embodiments of the present application do not limit this.

[0169] In some embodiments, on the basis of the above embodiments, the overall flow of the battery thermal runaway triggering method is exemplarily introduced and described taking the example of the embodiments of the present application in which the guide assembly is arranged between the first perforation and the second perforation, and the moving assembly 122 includes a driving member 122a and a moving member 122b. FIG. 10 is a flowchart of a battery thermal runaway triggering method provided by some other embodiments of the present application. In combination with FIGS. 8 and 10, the method of the embodiments of the present application can include the following steps:

[0170] Step S1001, opening the top cover of the target battery pack.

[0171] Step S1002, performing full discharge processing on the target battery cell in the target battery pack.

[0172] Exemplarily, the target battery cell in the target battery pack can be subjected to full discharge processing according to a second preset rate.

[0173] Step S1003, perforating a first position in the top cover of the target battery pack to form a first perforation at the first position.

[0174] Exemplarily, the diameter of the first perforation can be 3 mm.

[0175] Step S1004, perforating a second position in the top cover of the target battery cell to form a second perforation at the second position.

[0176] Exemplarily, the diameter of the second perforation can be 1 mm.

[0177] Step S1005, arranging a guide assembly between the first perforation and the second perforation, and arranging a second sealing member between the guide assembly and the second perforation.

[0178] Exemplarily, the outer diameter of the guide assembly can be 3 mm, and the inner diameter can be 1.5 mm.

[0179] Exemplarily, AB glue can be arranged between the guide assembly 14 and the second perforation to form the second sealing member.

[0180] Step S1006, performing full charge processing on the target battery cell to a preset trigger SOC.

[0181] Exemplarily, the target battery cell can be subjected to full charge processing to the preset trigger SOC according to a first preset rate.

[0182] Step S1007, the temperature collection assembly is arranged on the top cover of the target battery cell and the top cover of each battery cell adjacent to the target battery cell in the target battery pack.

[0183] Step S1008, the cap part of the puncture assembly is grabbed by the grabbing assembly.

[0184] Step S1009, the moving part in the moving assembly is driven by the driving part in the moving assembly to move along the first preset direction at the first moving speed, so as to drive the grabbing assembly to move towards the direction close to the top cover of the target battery cell, and thus the puncture part of the puncture assembly sequentially passes through the first puncture and the second puncture to penetrate into the inside of the target battery cell, so as to pierce the target component in the target battery cell and trigger the target battery cell to have thermal runaway from inside to outside.

[0185] For example, the cap part of the puncture assembly sealingly covers the first puncture.

[0186] Step S1011, in the case that the target battery cell has thermal runaway, the cap part of the puncture assembly is released by the grabbing assembly.

[0187] Step S1012, the grabbing assembly is driven by the moving assembly to move away from the top cover of the target battery pack.

[0188] In the present application, the first puncture is formed in the top cover of the target battery pack and the second puncture is formed in the top cover of the target battery cell by punching the top cover of the target battery pack and the top cover of the target battery cell respectively, so that the damage and interference to the target battery cell in the process of directly puncturing the target battery cell (without pre-punching) can be reduced, and the local puncture micro-short circuit of the target battery cell can be realized, so that the actual battery thermal runaway working condition can be more equivalent. The cap part of the puncture assembly is grabbed by the grabbing assembly, and the moving part in the moving assembly is driven by the driving part in the moving assembly to move along the first preset direction at the first moving speed, so as to drive the grabbing assembly to move towards the direction close to the top cover of the target battery cell, and thus the puncture part of the puncture assembly sequentially passes through the first puncture and the second puncture to directly penetrate into the inside of the target battery cell, so as to pierce the target component in the target battery cell, and the inside of the target battery cell can have local short circuit at the moment when the puncture part pierces the target component, so as to cause the target battery cell to have rapid temperature rise, and thus trigger the target battery cell to have thermal runaway from inside to outside (it is verified that the instantaneous temperature rise rate dT / dt of the target battery cell through the present embodiment is ≥1 ℃ / s and lasts for more than 3s, and no open fire appears). It can be seen that the present embodiment can better trigger local internal short and thermal runaway, so that the actual battery thermal runaway scene can be better simulated.

[0189] It should be noted that the battery thermal runaway triggering method and system of the embodiments of the present application can trigger any position of the battery cell of different battery packs, and can also be applied to market end to conduct sampling inspection on market end battery products, and has the advantages of strong flexibility, simple triggering method, and equivalent triggering result and actual thermal runaway working condition.

[0190] The implementation manners of the steps in the embodiments of the present application can refer to the related contents in the above-mentioned embodiments, which will not be described here.

[0191] In some embodiments, the embodiments of the present application also provide a battery thermal runaway triggering system, which can include a charging and discharging device and a liftable grabbing device.

[0192] The charging and discharging device is configured to charge a target battery cell in a target battery pack to a preset SOC; the first position of the shell of the target battery pack is provided with a first perforation, and the second position of the shell of the target battery cell is provided with a second perforation; and the projection of the first perforation on the shell of the target battery cell intersects with the second perforation.

[0193] The liftable grabbing device is configured to control the puncture part of the puncture assembly to sequentially puncture into the interior of the target battery cell through the first perforation and the second perforation, and the cap part of the puncture assembly covers the first perforation; the puncture part and the cap part are connected with each other, and the cap part is located at one end of the axial direction of the puncture part.

[0194] In some embodiments, the puncture assembly further includes a first sealing member arranged on one side of the cap part; and in the case that the cap part covers the first perforation, the first sealing member is located between the cap part and the first perforation.

[0195] In some embodiments, the length of the puncture part is greater than the vertical distance between the shell of the target battery pack and the shell of the target battery cell.

[0196] In some embodiments, the system further includes a guide assembly; and the guide assembly is arranged between the first perforation and the second perforation, and is configured to guide the puncture part to sequentially puncture into the interior of the target battery cell through the first perforation and the second perforation along the extension direction of the guide assembly.

[0197] In some embodiments, the system further includes a second sealing member, and the second sealing member is arranged between the guide assembly and the second perforation.

[0198] In some embodiments, the first position of the top cover of the target battery pack is provided with a first perforation, and the second position of the top cover of the target battery cell is provided with a second perforation.

[0199] In some embodiments, the projection of the first perforation on the shell of the target battery cell can cover the second perforation.

[0200] In some embodiments, the liftable grabbing device comprises:

[0201] a grabbing component for grabbing the cap part of the puncturing component;

[0202] a moving component connected with the grabbing component, for driving the grabbing component to move towards the shell of the target battery cell, so as to drive the puncturing part of the puncturing component to sequentially pass through the first and second perforations and pierce into the interior of the target battery cell.

[0203] In some embodiments, the moving component comprises a driving member and a moving member; wherein the grabbing component is connected with the moving member;

[0204] the driving member is configured to drive the moving member to move along a first preset direction at a first moving speed, so as to drive the grabbing component to move towards the shell of the target battery cell.

[0205] In some embodiments, the grabbing component is further configured to release the cap part of the puncturing component in the case that the target battery cell occurs thermal runaway;

[0206] the moving component is further configured to drive the grabbing component to move away from the shell of the target battery pack.

[0207] In some embodiments, the driving member is further configured to drive the moving member in the moving component to move along a second preset direction at a second moving speed, so as to drive the grabbing component to move away from the shell of the target battery pack.

[0208] In some embodiments, the charging and discharging device is further configured to perform full discharge processing on the target battery cell.

[0209] In some embodiments, the diameter of the puncturing part is 0.5mm-1mm.

[0210] In some embodiments, the material of the puncturing part is any one of the following: aluminum alloy, copper alloy, tungsten steel alloy.

[0211] In some embodiments, the diameter of the first perforation is 3mm-4mm; and / or,

[0212] the diameter of the second perforation is 1mm-2mm.

[0213] In some embodiments, the shell of the target battery cell and the shells of the battery cells adjacent to the target battery cell in the target battery pack are each provided with a temperature acquisition component;

[0214] the temperature acquisition component is configured to acquire the temperature of the corresponding battery cell.

[0215] In the embodiments of the present application, the related content of each component in the battery thermal runaway triggering system can refer to the related content in the above-mentioned battery thermal runaway triggering method embodiments, which will not be described here again.

[0216] It should be understood that, although the steps in the flowcharts involved in the above embodiments are shown in sequence according to the arrows, the steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of the steps is not strictly limited in sequence, and the steps can be executed in other sequences. Moreover, at least some of the steps in the flowcharts involved in the above embodiments can include multiple steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the steps or stages is not necessarily sequential, but can be executed in rotation or alternation with at least some of the other steps or the steps or stages in the other steps.

[0217] It can be understood by those of ordinary skill in the art that implementing all or part of the above method can be instructed by a computer program to relevant hardware, and the computer program can be stored in a non-volatile computer readable storage medium, and when executed, can include the flow of the above method.

[0218] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: it can still modify the technical solutions recorded in the above embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application. In particular, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A battery thermal runaway trigger method, wherein, The method comprises: Punching a first position of a shell of a target battery pack and a second position of a shell of a target battery cell respectively to form a first perforation at the first position and a second perforation at the second position; wherein the target battery cell is located in the target battery pack, and a projection of the first perforation on the shell of the target battery cell intersects with the second perforation; Charging the target battery cell to a preset SOC; Controlling a piercing part of a piercing assembly to sequentially pierce into an interior of the target battery cell through the first perforation and the second perforation, and a cap part of the piercing assembly covers the first perforation; wherein the piercing part and the cap part are connected with each other, and the cap part is located at one end of the piercing part in an axial direction.

2. The method of claim 1, wherein, In a case where a guide assembly is arranged between the first perforation and the second perforation, the control of the piercing part of the piercing assembly to sequentially pierce into the interior of the target battery cell through the first perforation and the second perforation comprises: Guiding the piercing part to sequentially pierce into the interior of the target battery cell through the first perforation and the second perforation along an extension direction of the guide assembly through the guide assembly.

3. The method of claim 1 or 2, wherein, The punching of the first position of the shell of the target battery pack and the second position of the shell of the target battery cell respectively to form the first perforation at the first position and the second perforation at the second position comprises: Punching a first position of a top cover of a target battery pack and a second position of a top cover of a target battery cell respectively to form the first perforation at the first position and the second perforation at the second position.

4. The method of any one of claims 1-3, wherein, The projection of the first perforation on the shell of the target battery cell can cover the second perforation.

5. The method of any one of claims 1-4, wherein, The control of the piercing part of the piercing assembly to sequentially pierce into the interior of the target battery cell through the first perforation and the second perforation comprises: Grasping the cap part of the piercing assembly through a grasping assembly; Driving the piercing part of the piercing assembly to sequentially pierce into the interior of the target battery cell through the first perforation and the second perforation by moving the grasping assembly towards the shell of the target battery cell through a moving assembly.

6. The method of claim 5, wherein, The moving of the grasping assembly towards the shell of the target battery cell through the moving assembly comprises: Driving a moving part in the moving assembly to move along a first preset direction at a first moving speed through a driving part in the moving assembly to drive the grasping assembly to move towards the shell of the target battery cell.

7. The method of claim 6, wherein, The first moving speed is 1 mm / s to 8 mm / s.

8. The method of any one of claims 5-7, wherein, The method further comprises: Releasing the cap part of the piercing assembly through the grasping assembly in a case where the target battery cell occurs thermal runaway; Driving the grasping assembly to move away from the shell of the target battery pack through the moving assembly.

9. The method of claim 8, wherein, The moving of the grasping assembly away from the shell of the target battery pack through the moving assembly comprises: The driving member in the moving assembly drives the moving member in the moving assembly to move along a second preset direction at a second moving speed, so as to drive the grabbing assembly to move away from the shell of the target battery pack.

10. The method of claim 9, wherein, The second moving speed is 3 cm / s to 5 cm / s.

11. The method of any one of claims 1-10, wherein, Before the sealing and punching device punches the first position of the shell of the target battery pack and the second position of the shell of the target battery cell, the method further comprises: full discharge processing of the target battery cell.

12. A battery thermal runaway triggering system, wherein, The system comprises: a charging and discharging device configured to charge a target battery cell in a target battery pack to a preset SOC; wherein a first position of a shell of the target battery pack is provided with a first perforation, and a second position of a shell of the target battery cell is provided with a second perforation; a projection of the first perforation on the shell of the target battery cell intersects with the second perforation; a liftable grabbing device configured to control a puncture part of a puncture assembly to sequentially puncture into an interior of the target battery cell through the first perforation and the second perforation, and a cap part of the puncture assembly covers the first perforation; wherein the puncture part and the cap part are connected to each other, and the cap part is located at one end in an axial direction of the puncture part.

13. The battery thermal runaway trigger system of claim 12, wherein, The puncture assembly further comprises a first sealing member arranged on one side of the cap part; wherein, in a case where the cap part covers the first perforation, the first sealing member is located between the cap part and the first perforation.

14. The battery thermal runaway triggering system of claim 12 or 13, wherein, The length of the puncture part is greater than a vertical distance between the shell of the target battery pack and the shell of the target battery cell.

15. The battery thermal runaway trigger system of any one of claims 12-14, wherein, The system further comprises a guide assembly; wherein the guide assembly is arranged between the first perforation and the second perforation, and is configured to guide the puncture part to sequentially puncture into the interior of the target battery cell through the first perforation and the second perforation along an extension direction of the guide assembly.

16. The battery thermal runaway trigger system of claim 15, wherein, The system further comprises a second sealing member; wherein the second sealing member is arranged between the guide assembly and the second perforation.

17. The battery thermal runaway trigger system of any one of claims 12-16, wherein, A first position of a top cover of the target battery pack is provided with the first perforation, and a second position of a top cover of the target battery cell is provided with the second perforation.

18. The battery thermal runaway trigger system of any one of claims 12-17, wherein, A projection of the first perforation on the shell of the target battery cell can cover the second perforation.

19. The battery thermal runaway trigger system of any one of claims 12-18, wherein, The liftable grabbing device comprises: a grabbing assembly configured to grab the cap part of the puncture assembly; a moving assembly connected to the grabbing assembly, configured to drive the grabbing assembly to move towards the shell of the target battery cell, so as to drive the puncture part of the puncture assembly to sequentially puncture into the interior of the target battery cell through the first perforation and the second perforation.

20. The battery thermal runaway triggering system of claim 19, wherein, The moving assembly comprises a driving member and a moving member; wherein the grabbing assembly is connected to the moving member; The driving member is configured to drive the moving member to move along a first preset direction at a first moving speed, so as to drive the grabbing assembly to move towards the shell of the target battery cell.

21. The battery thermal runaway trigger system of claim 20, wherein, The grabbing assembly is further configured to release the cap part of the puncture assembly in a case where the target battery cell occurs thermal runaway. The moving assembly is further configured to drive the grabbing assembly to move away from the shell of the target battery pack.

22. The battery thermal runaway trigger system of claim 21, wherein, The driving member is further configured to drive the moving member in the moving assembly to move along a second preset direction at a second moving speed, so as to drive the grabbing assembly to move away from the shell of the target battery pack.

23. The battery thermal runaway trigger system of any one of claims 12-22, wherein, The charging and discharging device is further configured to perform full discharge on the target battery cell.

24. The battery thermal runaway trigger system of any one of claims 12-23, wherein, The diameter of the puncture part is 0.5 mm to 1 mm.

25. The battery thermal runaway trigger system of any one of claims 12-24, wherein, The material of the puncture part is any one of the following: aluminum alloy, copper alloy, tungsten steel alloy.

26. The battery thermal runaway trigger system of any one of claims 12-25, wherein, The diameter of the first puncture is 3 mm to 4 mm; and / or, The diameter of the second puncture is 1 mm to 2 mm.

27. The battery thermal runaway trigger system of any one of claims 12-26, wherein, The temperature acquisition assembly is arranged on the shell of the target battery cell and the shells of the battery cells adjacent to the target battery cell in the target battery pack. The temperature acquisition assembly is configured to acquire the temperature of the corresponding battery cell.

Images