Battery thermal runaway triggering method and system

Abstract

The invention relates to a battery thermal runaway triggering method and system, and the method comprises the steps: carrying out the punching of a first position in a top cover of a target battery pack and a second position in a top cover of a target battery cell, so as to form a first through hole in the first position, and to form a second through hole in the second position; wherein the target battery cell is located in the target battery pack. And further, enabling a laser transmission line to sequentially pass through the first through hole and the second through hole to extend into the target battery cell, and charging the target battery cell to a preset SOC (State of Charge). And further, controlling the laser equipment to transmit the target laser through the laser transmission line so as to trigger the thermal runaway of the target battery cell. The embodiment of the invention can be equivalent to an actual battery thermal runaway scene.

Description

Technical Field

[0001] This application relates to the field of battery technology, and in particular to a method and system for triggering battery thermal runaway. Background Technology

[0002] The main purpose of thermal runaway testing for batteries (or battery packs) is to simulate the phenomenon of thermal runaway that occurs during normal use due to defects in the battery product itself.

[0003] In related technologies, thermal runaway is triggered by installing a heating plate on the outside of the battery. However, these technologies cannot be equated to actual battery thermal runaway scenarios. Summary of the Invention

[0004] In view of the above problems, this application provides a battery thermal runaway triggering method and system, which can solve the problem that related technologies cannot be equivalent to actual battery thermal runaway scenarios.

[0005] In a first aspect, this application provides a method for triggering battery thermal runaway, the method comprising:

[0006] Drilling is performed on a first position in the top cover of the target battery pack and a second position in the top cover 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.

[0007] The laser transmission line is inserted into the target battery cell through the first and second perforations in sequence.

[0008] Charge the target battery cell to the preset SOC;

[0009] The laser control device transmits the target laser through a laser transmission line to trigger thermal runaway in the target battery cell.

[0010] In this embodiment, a laser transmission line is used to extend into the target cell through a first perforation in the top cover of the target battery pack and a second perforation in the top cover of the target cell. The laser device is controlled to transmit the target laser through the laser transmission line to trigger thermal runaway in the target cell. On the one hand, the laser transmission line transmits the target laser output by the laser device into the target cell to trigger thermal runaway from the inside out. On the other hand, since the instantaneous energy of the target laser introduced into the target cell is high, it can quickly trigger thermal runaway in the target cell, resulting in less total energy injected into the target cell during the thermal runaway triggering process. Therefore, it can be equivalent to the actual battery thermal runaway scenario.

[0011] In some embodiments, charging the target battery cell to a preset SOC includes:

[0012] The target cell is fully charged to a preset trigger SOC so that when the target laser is input into the target cell, thermal runaway can be triggered more quickly.

[0013] In some embodiments, before drilling holes in a first position in the top cover of the target battery pack and a second position in the top cover of the target cell, the method further includes: fully filling the target cell so that the target cell in the target battery pack can be protected during the drilling process.

[0014] In some embodiments, before charging the target cell to a preset SOC, the method further includes: sealing the laser transmission line and each perforation so that in the event of thermal runaway of the target cell, thermal runaway gas and the like will still be discharged through the explosion-proof valve of the battery pack, so as to better simulate the battery thermal runaway scenario.

[0015] In some embodiments, the diameter of the first perforation is 1 mm to 2 mm; and / or,

[0016] The diameter of the second perforation is 1mm~2mm.

[0017] In some embodiments, the laser device is a pulsed laser device, and the operating parameters of the laser device include at least one of the following:

[0018] The average output power is 500W~1000W;

[0019] The frequency is adjustable from 1kHz to 4000kHz.

[0020] The pulse width is 2ns to 500ns.

[0021] In some embodiments, the laser transmission line includes: a first sub-transmission line and a second sub-transmission line; wherein one end of the first sub-transmission line is connected to a laser device, the other end of the first sub-transmission line is connected to one end of the second sub-transmission line, and the other end of the second sub-transmission line extends into the interior of the target battery cell; controlling the laser device to transmit target laser light through the laser transmission line includes:

[0022] The laser control device transmits the target laser from the first sub-transmission line to the second sub-transmission line, and then transmits the target laser into the target cell through the second sub-transmission line.

[0023] In this embodiment, the laser transmission line includes a first sub-transmission line and a second sub-transmission line. By controlling the laser device to transmit the target laser through the first sub-transmission line to the second sub-transmission line, and then through the second sub-transmission line to the interior of the target battery cell, in the event of thermal runaway of the target battery cell, only the second sub-transmission line closest to the target battery cell may be corroded, without corroding the first sub-transmission line or the laser device. Therefore, this embodiment is beneficial for protecting the laser device.

[0024] In some embodiments, a collimation adapter is further provided between the first sub-transmission line and the second sub-transmission line to control the laser device to transmit the target laser from the first sub-transmission line to the second sub-transmission line, and to transmit the target laser into the interior of the target cell through the second sub-transmission line, including:

[0025] The laser control device transmits the target laser to the collimation adapter via the first sub-transmission line to focus the target laser, obtaining a focused target laser, and then transmits the focused target laser to the second sub-transmission line; the focused target laser is then transmitted into the target cell via the second sub-transmission line.

[0026] In this embodiment, by providing a collimation adapter between the first and second sub-transmission lines, the target laser can be focused, reducing signal loss and distortion during transmission. This improves the transmission efficiency and signal quality of the target laser, thus enhancing the efficiency of triggering thermal runaway. Furthermore, the second sub-transmission line also protects the collimation adapter.

[0027] Secondly, this application provides a battery thermal runaway triggering system, the system comprising:

[0028] A charging and discharging device is used to charge a target cell in a target battery pack to a preset SOC; wherein a first perforation is provided at a first position in the top cover of the target battery pack, and a second perforation is provided at a second position in the top cover of the target cell.

[0029] A laser transmission line extends into the interior of the target battery cell through a first perforation and a second perforation in sequence.

[0030] A laser device, connected to a laser transmission line, is used to transmit a target laser through the laser transmission line when the laser transmission line extends into the interior of the target battery cell through a first perforation and a second perforation in sequence, so as to trigger thermal runaway in the target battery cell.

[0031] In some embodiments, the charging and discharging device is specifically used to: fully charge the target battery cell to a preset trigger SOC.

[0032] In some embodiments, the charging and discharging equipment is also used to perform a full discharge process on the target battery cell.

[0033] In some embodiments, the laser transmission line includes: a first sub-transmission line and a second sub-transmission line; wherein, one end of the first sub-transmission line is connected to the laser device, the other end of the first sub-transmission line is connected to one end of the second sub-transmission line, and the other end of the second sub-transmission line extends into the interior of the target cell.

[0034] The laser device is specifically used to transmit the target laser from the first sub-transmission line to the second sub-transmission line, and to transmit the target laser into the interior of the target cell via the second sub-transmission line.

[0035] In some embodiments, a collimation adapter is further provided between the first sub-transmission line and the second sub-transmission line;

[0036] The laser device is specifically used to transmit the target laser to the collimation adapter via the first sub-transmission line to focus the target laser and obtain the focused target laser. The focused target laser is then transmitted to the second sub-transmission line and transmitted to the inside of the target cell via the second sub-transmission line.

[0037] In some embodiments, an insulating layer is provided on the outer surface of the laser transmission line.

[0038] In some embodiments, a temperature acquisition component is provided on the top cover of the target cell and on the top cover of each cell adjacent to the target cell in the target battery pack.

[0039] Temperature acquisition component, used to acquire the temperature of the corresponding battery cell.

[0040] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0041] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0042] Figure 1 This is a schematic diagram of the structure of a battery thermal runaway triggering system provided in some embodiments of this application;

[0043] Figure 2 This is a flowchart illustrating a battery thermal runaway triggering method provided in some embodiments of this application;

[0044] Figure 3 This is a schematic diagram of the structure of a battery thermal runaway triggering system provided in some other embodiments of this application;

[0045] Figure 4 A schematic flowchart illustrating a battery thermal runaway triggering method provided in other embodiments of this application;

[0046] Figure 5 This is a schematic diagram of the structure of a battery thermal runaway triggering system provided in some other embodiments of this application;

[0047] Figure 6 This is a flowchart illustrating a battery thermal runaway triggering method provided in some other embodiments of this application. Detailed Implementation

[0048] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0049] 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 pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the term "comprising" and any variations thereof in the specification, claims and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0050] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more (including two), unless otherwise explicitly defined.

[0051] The battery thermal runaway triggering method and system provided in this application can be applied to battery thermal runaway propagation testing (or battery thermal runaway detection); of course, it can also be applied to other application scenarios.

[0052] In related technologies, thermal runaway is triggered by installing a heating plate on the outside of the battery. This external heating plate method requires the battery casing to first fail and deform, then triggering thermal runaway in the internal battery cells; that is, the battery failure proceeds from the outside in. Since actual battery thermal runaway scenarios are usually caused by internal short circuits within the battery cells (i.e., failure proceeds from the inside out), this technology cannot be equivalent to a real-world battery thermal runaway scenario. Furthermore, the external heating plate method typically requires a long time, injecting excessive energy into the battery cells, which also contributes to the inability of this technology to be equivalent to a real-world battery thermal runaway scenario.

[0053] To address the problems in related technologies, this application proposes a method where a laser transmission line is inserted into the target cell through a first perforation in the top cover of the target battery pack and a second perforation in the top cover of the target cell. The laser device is controlled to transmit the target laser through the laser transmission line to trigger thermal runaway in the target cell. On one hand, the laser transmission line transmits the target laser output from the laser device into the target cell, triggering thermal runaway from the inside out. On the other hand, because the instantaneous energy of the target laser introduced into the target cell is high, it can quickly trigger thermal runaway, resulting in less total energy injected into the target cell during the thermal runaway triggering process. Therefore, it can be equivalent to a real-world battery thermal runaway scenario.

[0054] For ease of understanding, the relevant content of the battery thermal runaway triggering system will be described and explained in this application embodiment by way of example.

[0055] In some embodiments, Figure 1 This is a schematic diagram of the structure of a battery thermal runaway triggering system provided in some embodiments of this application, such as... Figure 1 As shown, the battery thermal runaway triggering system of this application embodiment may include: a charging and discharging device 11, a laser transmission line L, and a laser device 12.

[0056] For example, the charging and discharging device 11 can be connected to the target battery pack (or trigger battery pack) 10 to charge and discharge a target cell (or trigger cell) at a preset position in the target battery pack 10. The target battery pack 10 may include multiple cells C, with the target cell being one of the multiple cells C. It should be understood that the target battery pack 10 may include a top cover 101 and a housing 102, with the multiple cells C located in the housing 102 of the target battery pack 10. Furthermore, a first through hole may be provided at a first position in the top cover 101 of the target battery pack 10, and a second through hole may be provided at a second position in the top cover of the target cell, so that the laser transmission line L can sequentially extend into the interior of the target cell through the first and second through holes.

[0057] For example, the laser device 12 can be connected to the laser transmission line L to connect to the target cell in the target battery pack via the laser transmission line L, so that the target laser can be transmitted to the inside of the target cell in the target battery pack via the laser transmission line L to trigger thermal runaway of the target cell.

[0058] Of course, the battery thermal runaway triggering system in this application embodiment may also include other devices, such as sealing perforation devices.

[0059] In some embodiments, Figure 2 This is a flowchart illustrating a battery thermal runaway triggering method provided in some embodiments of this application, such as... Figure 2 As shown, the battery thermal runaway triggering method in this application embodiment may include the following steps:

[0060] Step S201: Drill holes in a first position in the top cover of the target battery pack and a second position in the top cover of the target cell, respectively, to form a first perforation in the first position and a second perforation in the second position; wherein the target cell is located in the target battery pack.

[0061] In this step, on the one hand, a hole can be drilled in the first position of the top cover of the target battery pack to form a first perforation, so that the laser transmission line can extend into the interior of the target battery pack through the first perforation. On the other hand, a hole can be drilled in the second position of the top cover of the target cell in the target battery pack to form a second perforation, so that the laser transmission line can extend into the interior of the target cell through the second perforation.

[0062] In this embodiment, the diameters of the first and second perforations can be greater than or equal to the diameter of the laser transmission line, so that the laser transmission line can pass through the first and second perforations. For example, the diameters of the first and second perforations can be slightly larger than the diameter of the laser transmission line, which allows the laser transmission line to pass through the first and second perforations while also minimizing the gaps between the laser transmission line and each perforation.

[0063] For example, the outer surface of the laser transmission line in this application embodiment may be provided with an insulating layer, which is beneficial not only to protect the target battery pack, but also to protect the test personnel.

[0064] For example, the laser transmission line in this application embodiment may include, but is not limited to, optical fiber; the diameter of the first perforation in this application embodiment may be 1mm to 2mm; and / or, the diameter of the second perforation may be 1mm to 2mm.

[0065] For example, if the diameter of the laser transmission line can be 1 mm, then the diameters of the first and second perforations can be greater than 1 mm but very close to 1 mm.

[0066] It should be understood that the order in which the top cover of the target battery pack is drilled and the top cover of the target battery cell are drilled in the embodiments of this application is not limited.

[0067] In one possible implementation, a drilling device can be used to drill holes at a first position in the top cover of the target battery pack and a second position in the top cover of the target battery cell, respectively, to form a first perforation at the first position and a second perforation at the second position. The drilling device may include, but is not limited to, any of the following: a pneumatic drilling machine, a laser drilling machine, an ultrasonic drilling machine, an electric drilling machine, or a hydraulic punching machine.

[0068] In another possible implementation, holes can be drilled in the first position of the top cover of the target battery pack and the second position of the top cover of the target cell by means of chemical etching, electrical discharge drilling or mechanical punching, so as to form a first perforation in the first position and a second perforation in the second position.

[0069] Of course, other methods can also be used to drill holes at the first position in the top cover of the target battery pack and the second position in the top cover of the target cell.

[0070] Step S202: Insert the laser transmission line into the interior of the target battery cell through the first and second perforations in sequence.

[0071] In this step, a laser transmission line is inserted into the target battery pack through a first perforation and then further into the target battery cell through a second perforation. It should be understood that one end of the laser transmission line is connected to a laser device, and the other end extends into the target battery cell through the first and second perforations, facilitating the transmission of the target laser output from the laser device into the target battery cell.

[0072] Step S203: Charge the target battery cell to the preset SOC.

[0073] In this step, the target cell is charged to a preset SOC so that when a target laser is subsequently input into the target cell, thermal runaway can be triggered.

[0074] In some embodiments, the preset SOC may include, but is not limited to, a preset trigger SOC. This can be achieved by fully charging the target cell to the preset trigger SOC, so that when a target laser is subsequently input into the target cell, thermal runaway can be triggered more quickly. For example, the preset trigger SOC may include, but is not limited to, 90% to 100%.

[0075] In some embodiments, the preset SOC may include, but is not limited to, a preset non-trigger SOC. This can be achieved by charging the target cell to the preset SOC so that subsequent input of a target laser into the target cell can trigger thermal runaway. For example, the preset non-trigger SOC may be less than the preset trigger SOC.

[0076] For example, the target battery cell can be charged to a preset SOC at a first preset rate, wherein the first preset rate may include, but is not limited to, 0.33C to 1C. For instance, the first preset rate may be 1C.

[0077] Another example is that the target battery cell can be charged to a preset SOC by a preset rate of change.

[0078] In one possible implementation, the target battery cell can be charged to a preset SOC using a charging and discharging device.

[0079] Another possible implementation is to charge the target battery cell to a preset SOC using a smart charging device or a dedicated charger.

[0080] Step S204: Control the laser device to transmit the target laser through the laser transmission line to trigger thermal runaway of the target cell.

[0081] In this step, the laser device can be controlled to transmit the target laser to the inside of the target cell in the target battery pack through the laser transmission line. Since the instantaneous energy of the target laser is very high, it can quickly cause a severe temperature rise inside the target cell, so as to quickly break through the separator in the target cell to cause a short circuit, thereby quickly triggering thermal runaway of the target cell in the target battery pack.

[0082] In one possible implementation, the laser device can be a pulsed laser device, and the operating parameters of the laser device may include, but are not limited to, at least one of the following: average output power of 500W~1000W; frequency adjustable range of 1KHz~4000KHz; pulse width of 2ns~500ns.

[0083] It should be understood that in the embodiments of this application, a pulsed laser device can be controlled to transmit a pulsed laser (i.e., the target laser) to the inside of the target cell through a laser transmission line, which can trigger thermal runaway of the target cell.

[0084] In another possible implementation, the laser device can be a continuous wave laser device.

[0085] For example, the continuous wave laser device can be controlled to activate for a preset ultra-short duration to transmit the target laser to the inside of the target cell through the laser transmission line, thereby triggering thermal runaway of the target cell. The preset ultra-short duration can be 2ns to 500ns.

[0086] In summary, in this embodiment, a first perforation is formed at the first position and a second perforation is formed at the second position by drilling holes at a first position in the top cover of the target battery pack and a second perforation at the second position, respectively; wherein the target battery cell is located in the target battery pack. Further, a laser transmission line is sequentially inserted into the interior of the target battery cell through the first and second perforations, and the target battery cell is charged to a preset SOC. Further, a laser device is controlled to transmit a target laser through the laser transmission line to trigger thermal runaway in the target battery cell. As can be seen, compared with the external heating plate method in related technologies, in this embodiment, the laser transmission line extends into the interior of the target cell through the first perforation in the top cover of the target battery pack and the second perforation in the top cover of the target cell, and the laser device is controlled to transmit the target laser through the laser transmission line to trigger thermal runaway of the target cell. On the one hand, the laser transmission line transmits the target laser output by the laser device into the interior of the target cell to trigger thermal runaway from the inside out. On the other hand, since the instantaneous energy of the target laser introduced into the interior of the target cell is high, it can quickly trigger thermal runaway of the target cell, so the total energy injected into the target cell during the thermal runaway triggering process is less. Therefore, it can be equivalent to the actual battery thermal runaway scenario.

[0087] In some embodiments, considering that there may be certain safety hazards in drilling the target cell when the target cell has a large amount of power, the target cells in the target battery pack can be fully discharged before step S201, so as to protect the target cells in the target battery pack during the drilling process.

[0088] For example, the target cells in the target battery pack can be fully discharged at a second preset rate, wherein the second preset rate may include, but is not limited to, 0.33C to 1C. For instance, the second preset rate may be 0.33C.

[0089] In one possible implementation, the target cells in the target battery pack can be fully discharged using a charging and discharging device.

[0090] Another possible implementation method is to fully discharge the target cells in the target battery pack by means of bulb discharge, electrolyte discharge, or high-power resistor discharge.

[0091] Of course, other methods can also be used to fully discharge the target cells in the target battery pack.

[0092] In some embodiments, considering that in actual battery thermal runaway scenarios, thermal runaway gases and the like will be discharged through the explosion-proof valve of the battery pack, in order to better simulate battery thermal runaway scenarios, the embodiments of this application may perform sealing treatment between the laser transmission line and each perforation before the above step S203.

[0093] In this embodiment, a sealing treatment can be performed between the laser transmission line and the second perforation in the top cover of the target cell, and a sealing treatment can be performed between the laser transmission line and the first perforation in the top cover of the target battery pack, so that in the event of thermal runaway of the target cell, thermal runaway gas and the like can still be discharged through the explosion-proof valve of the battery pack, so as to better simulate the battery thermal runaway scenario.

[0094] In one possible implementation, a sealing device can be used to seal the laser transmission line and each perforation. This sealing device may include, but is not limited to, any of the following: a glue dispensing machine, a sealant nail vacuum sealing machine, or a sealant gun.

[0095] For example, AB glue or other high-strength adhesives can be placed between the laser transmission line and the first and second perforations respectively using a sealing device for sealing.

[0096] In another possible implementation, the laser transmission line and each perforation can be sealed using sealing gaskets or sealing rings.

[0097] Of course, other methods can also be used to seal the laser transmission line and each perforation.

[0098] In some embodiments, considering that thermal runaway of the target battery cell may corrode the lines and / or equipment connected to the target battery cell, the laser transmission line L in this application embodiment can be set as at least two sub-transmission lines to help protect the laser equipment.

[0099] Figure 3 This is a schematic diagram of the structure of a battery thermal runaway triggering system provided in other embodiments of this application, such as... Figure 3 As shown, the laser transmission line L in this embodiment may include: a first sub-transmission line L1 and a second sub-transmission line L2; wherein, one end of the first sub-transmission line L1 may be connected to the laser device 12, the other end of the first sub-transmission line L1 is connected to one end of the second sub-transmission line L2, and the other end of the second sub-transmission line L2 extends into the interior of the target cell.

[0100] For example, the length of the first sub-transmission line L1 can be less than the length of the second sub-transmission line L2.

[0101] In some embodiments, Figure 4 This is a flowchart illustrating a battery thermal runaway triggering method provided in other embodiments of this application, in conjunction with... Figure 3 As shown, this application embodiment provides an exemplary description of the relevant content of step S204 described above. For example... Figure 4 As shown, step S204 above may include:

[0102] Step S2041: Control the laser device to transmit the target laser to the second sub-transmission line through the first sub-transmission line, and transmit the target laser into the target cell through the second sub-transmission line.

[0103] In this step, the laser control device 12 can transmit the target laser to the second sub-transmission line L2 through the first sub-transmission line L1, and transmit the target laser into the target cell through the second sub-transmission line L2 to trigger thermal runaway of the target cell.

[0104] In this embodiment, by including a first sub-transmission line L1 and a second sub-transmission line L2 in the laser transmission line L, in the event of thermal runaway of the target battery cell, only the second sub-transmission line L2 closest to the target battery cell may be corroded, but the first sub-transmission line L1 will not be corroded, and the laser device 12 will not be corroded. Therefore, this embodiment is beneficial for protecting the laser device. It should be understood that the second sub-transmission line L2 in this embodiment is a replaceable transmission line, that is, if the currently used second sub-transmission line L2 fails, it can be replaced with another second sub-transmission line.

[0105] As can be seen, in this embodiment, the laser transmission line includes a first sub-transmission line and a second sub-transmission line. By controlling the laser device to transmit the target laser through the first sub-transmission line to the second sub-transmission line, and then through the second sub-transmission line to the interior of the target cell, in the event of thermal runaway of the target cell, only the second sub-transmission line closest to the target cell may be corroded, but the first sub-transmission line will not be corroded, and the laser device will not be corroded. Therefore, this embodiment is beneficial for protecting the laser device.

[0106] In some embodiments, Figure 5 This is a schematic diagram of the structure of a battery thermal runaway triggering system provided in other embodiments of this application, such as... Figure 5 As shown, in this embodiment of the application, a collimation adapter 13 may also be provided between the first sub-transmission line L1 and the second sub-transmission line L2 to facilitate focusing of the target laser, thereby reducing the loss and distortion of the optical signal during transmission, which is beneficial to improving the transmission efficiency and signal quality of the target laser.

[0107] For example, the collimation adapter 13 may include, but is not limited to, a collimation adapter; of course, it may also be replaced by other devices with focusing functions.

[0108] In this application, step S2041 may include: controlling the laser device to transmit the target laser to the collimation adapter through the first sub-transmission line to focus the target laser, obtain the focused target laser, and transmit the focused target laser to the second sub-transmission line; further, transmitting the focused target laser to the inside of the target cell through the second sub-transmission line.

[0109] In this embodiment, the control laser device 12 transmits the target laser to the collimation adapter 13 via the first sub-transmission line L1, so that the collimation adapter 13 can focus the target laser to obtain a focused target laser. It should be noted that by focusing the target laser, the loss and distortion of the optical signal during transmission can be reduced, thereby improving the transmission efficiency and signal quality of the target laser.

[0110] Furthermore, the focused target laser is transmitted to the second sub-transmission line L2 through the collimation adapter 13, and the focused target laser is transmitted to the inside of the target cell through the second sub-transmission line L2 to trigger thermal runaway of the target cell.

[0111] As can be seen, in this embodiment, by providing a collimation adapter between the first and second sub-transmission lines, the target laser can be focused, reducing signal loss and distortion during transmission. This improves the transmission efficiency and signal quality of the target laser, thus enhancing the efficiency of triggering thermal runaway. Furthermore, the second sub-transmission line also protects the collimation adapter.

[0112] In some embodiments, in order to facilitate subsequent research and analysis of the thermal runaway process of the target cell in the target battery pack, the top cover of the target cell and the top cover of each cell adjacent to the target cell in the target battery pack may be provided with corresponding temperature acquisition components; wherein, the temperature acquisition components can be used to acquire the temperature of the corresponding cell.

[0113] For example, the temperature acquisition component may include, but is not limited to, a temperature sensor or a thermocouple. It should be understood that the temperature acquisition component in this embodiment can record the temperature of the corresponding battery cell in real time, or can record the temperature of the corresponding battery cell at preset intervals.

[0114] It should be noted that the temperature acquisition component in this embodiment can also be set at other locations of the corresponding battery cell (such as the side wall of the battery cell), and this embodiment does not limit this.

[0115] In some embodiments, based on the above embodiments, combined with Figure 5As shown in the embodiments of this application, a pulsed laser device is used as an example to illustrate the overall process of the battery thermal runaway triggering method. Figure 6 This is a flowchart illustrating a battery thermal runaway triggering method provided in other embodiments of this application, such as... Figure 6 As shown, the method in this application embodiment may include the following steps:

[0116] Step S601: Open the top cover of the target battery pack.

[0117] Step S602: Fully discharge the target cells in the target battery pack.

[0118] For example, the target cells in the target battery pack can be fully discharged at 0.33C.

[0119] Step S603: Drill a hole in the first position of the top cover of the target battery pack to form a first perforation at the first position.

[0120] For example, the diameter of the first perforation can be 1mm to 2mm.

[0121] Step S604: Drill a hole in the second position of the top cover of the target cell to form a second perforation at the second position.

[0122] For example, the diameter of the second perforation can be 1mm to 2mm.

[0123] Step S605: Insert the laser transmission line into the interior of the target battery cell through the first and second perforations in sequence, and seal the laser transmission line with each perforation.

[0124] For example, AB glue or other high-strength adhesives can be placed between the laser transmission line and the first and second perforations respectively for sealing.

[0125] Step S606: Fully charge the target battery cell to the preset trigger SOC.

[0126] For example, the target battery cell can be fully charged at 1C to a preset trigger SOC.

[0127] Step S607: Temperature acquisition components are installed on the top cover of the target cell and on the top cover of each cell adjacent to the target cell in the target battery pack.

[0128] Step S608: Install the top cover of the target battery pack and seal it.

[0129] Step S609: Control the pulsed laser device to transmit the target laser to the inside of the target cell through the laser transmission line to trigger thermal runaway of the target cell.

[0130] For example, the laser transmission line L may include a first sub-transmission line L1 and a second sub-transmission line L2, and a collimation adapter 13 is further provided between the first sub-transmission line L1 and the second sub-transmission line L2. The lengths and diameters of the first sub-transmission line L1 and the second sub-transmission line L2 can be referenced in Table 1. Additionally, some operating parameters of the pulsed laser device in this embodiment can also be referenced in Table 1.

[0131] Table 1 is a schematic table of some thermal runaway test parameters provided in the embodiments of this application.

[0132]

[0133] In summary, in this embodiment, a laser transmission line is used to extend into the target cell through the first perforation in the top cover of the target battery pack and the second perforation in the top cover of the target cell. The laser is transmitted into the target cell via the laser transmission line using a pulsed laser device. The instantaneous high energy of the pulse breaks down the separator in the target cell, causing a short circuit and quickly triggering thermal runaway in the target cell. In this method, thermal runaway is triggered from the inside out and the triggering energy is low. Therefore, it can not only be equivalent to the actual battery thermal runaway scenario, but also quickly trigger thermal runaway in the target cell in the target battery pack (it has been verified that the battery thermal runaway triggering method of this embodiment can induce a severe temperature rise in the target cell within 3s to 5s, thereby causing thermal runaway).

[0134] Furthermore, the laser transmission line includes a first sub-transmission line and a second sub-transmission line, with a collimation adapter between them. This design ensures that in the event of thermal runaway of the target battery cell, only the second sub-transmission line closest to the target cell will be corroded, without corroding the first sub-transmission line, the collimation adapter, or the laser device. Therefore, the embodiments of this application are advantageous in protecting the collimation adapter and the laser device. Moreover, by focusing the target laser through the collimation adapter, signal loss and distortion during transmission can be reduced, thereby improving the transmission efficiency and signal quality of the target laser and enhancing the efficiency of triggering thermal runaway.

[0135] In addition, in this embodiment of the application, by opening the top cover of the target battery pack, drilling holes in the top cover, inserting the laser transmission line, installing the top cover of the target battery pack, and controlling the laser device to emit the target laser, the target battery pack can be quickly and conveniently modified for thermal runaway testing without removing the battery cells.

[0136] In some embodiments, this application also provides a battery thermal runaway triggering system, which may include a charging and discharging device, a laser transmission line, and a laser device.

[0137] The charging and discharging equipment can be used to charge the target cell in the target battery pack to a preset SOC; wherein a first perforation is provided at a first position in the top cover of the target battery pack, and a second perforation is provided at a second position in the top cover of the target cell.

[0138] A laser transmission line extends into the interior of the target battery cell through a first perforation and a second perforation in sequence.

[0139] The laser device, connected to a laser transmission line, can be used to transmit a target laser through the laser transmission line when the laser transmission line extends into the interior of the target battery cell through the first and second perforations in sequence, thereby triggering thermal runaway in the target battery cell.

[0140] In some embodiments, the charging and discharging device is specifically used to: fully charge the target battery cell to a preset trigger SOC.

[0141] In some embodiments, the charging and discharging equipment can also be used to fully discharge the target battery cell.

[0142] In some embodiments, the laser transmission line may include: a first sub-transmission line and a second sub-transmission line; wherein, one end of the first sub-transmission line is connected to the laser device, the other end of the first sub-transmission line is connected to one end of the second sub-transmission line, and the other end of the second sub-transmission line extends into the interior of the target cell.

[0143] The laser device can be specifically used to transmit the target laser from the first sub-transmission line to the second sub-transmission line, and to transmit the target laser into the interior of the target cell via the second sub-transmission line.

[0144] In some embodiments, a collimation adapter is further provided between the first sub-transmission line and the second sub-transmission line; the laser device can be specifically used to transmit the target laser to the collimation adapter through the first sub-transmission line, so as to focus the target laser to obtain the focused target laser, transmit the focused target laser to the second sub-transmission line, and transmit the focused target laser into the interior of the target cell through the second sub-transmission line.

[0145] In some embodiments, an insulating layer is provided on the outer surface of the laser transmission line.

[0146] In some embodiments, a temperature acquisition component is provided on the top cover of the target cell and on the top cover of each cell adjacent to the target cell in the target battery pack; the temperature acquisition component is used to acquire the temperature of the corresponding cell.

[0147] In this embodiment, the relevant content of each component in the battery thermal runaway triggering system can be referred to the relevant content in the above embodiment of the battery thermal runaway triggering method, and will not be repeated here.

[0148] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0149] Those skilled in the art will understand that all or part of the processes in the above methods can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, the computer program can include the processes of the above methods.

[0150] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This 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 method for triggering battery thermal runaway, characterized in that, The method includes: Drilling is performed on a first position in the top cover of the target battery pack and a second position in the top cover 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; The laser transmission line is inserted into the interior of the target battery cell through the first and second perforations in sequence. Charge the target battery cell to a preset SOC; The laser control device transmits the target laser through the laser transmission line to trigger thermal runaway in the target battery cell.

2. The method according to claim 1, characterized in that, The process of charging the target battery cell to a preset SOC includes: The target battery cell is fully charged to a preset trigger SOC.

3. The method according to claim 1, characterized in that, Before drilling holes at a first location in the top cover of the target battery pack and a second location in the top cover of the target battery cell, the method further includes: The target battery cell is then fully discharged.

4. The method according to claim 1, characterized in that, Before charging the target battery cell to a preset SOC, the method further includes: The laser transmission line and each perforation are sealed.

5. The method according to any one of claims 1-4, characterized in that, The diameter of the first perforation is 1mm to 2mm; and / or, The diameter of the second perforation is 1mm to 2mm.

6. The method according to any one of claims 1-4, characterized in that, The laser device is a pulsed laser device, and the operating parameters of the laser device include at least one of the following: The average output power is 500W~1000W; The frequency is adjustable from 1kHz to 4000kHz. The pulse width is 2ns to 500ns.

7. The method according to any one of claims 1-4, characterized in that, The laser transmission line includes: a first sub-transmission line and a second sub-transmission line; wherein one end of the first sub-transmission line is connected to the laser device, the other end of the first sub-transmission line is connected to one end of the second sub-transmission line, and the other end of the second sub-transmission line extends into the interior of the target battery cell; controlling the laser device to transmit target laser light through the laser transmission line includes: The laser device is controlled to transmit the target laser from the first sub-transmission line to the second sub-transmission line, and to transmit the target laser into the target cell through the second sub-transmission line.

8. The method according to claim 7, characterized in that, A collimation adapter is also provided between the first sub-transmission line and the second sub-transmission line. The control laser device transmits the target laser from the first sub-transmission line to the second sub-transmission line, and transmits the target laser into the interior of the target cell through the second sub-transmission line, including: The laser device is controlled to transmit the target laser to the collimation adapter through the first sub-transmission line to focus the target laser, obtain the focused target laser, and then transmit the focused target laser to the second sub-transmission line. The focused target laser is transmitted into the target cell through the second sub-transmission line.

9. A battery thermal runaway triggering system, characterized in that, The system includes: A charging and discharging device is used to charge a target cell in a target battery pack to a preset SOC; wherein a first through hole is provided at a first position in the top cover of the target battery pack, and a second through hole is provided at a second position in the top cover of the target cell; A laser transmission line, which extends into the interior of the target battery cell through the first and second through holes in sequence; A laser device, connected to the laser transmission line, is used to transmit a target laser through the laser transmission line to trigger thermal runaway in the target battery cell when the laser transmission line extends into the interior of the target battery cell through the first perforation and the second perforation in sequence.

10. The battery thermal runaway triggering system according to claim 9, characterized in that, The charging and discharging equipment is specifically used for: The target battery cell is fully charged to a preset trigger SOC.

11. The battery thermal runaway triggering system according to claim 9, characterized in that, The charging and discharging equipment is also used to fully discharge the target battery cell.

12. The battery thermal runaway triggering system according to any one of claims 9-11, characterized in that, The laser transmission line includes: a first sub-transmission line and a second sub-transmission line; wherein, one end of the first sub-transmission line is connected to the laser device, the other end of the first sub-transmission line is connected to one end of the second sub-transmission line, and the other end of the second sub-transmission line extends into the interior of the target battery cell. The laser device is specifically used to transmit the target laser to the second sub-transmission line through the first sub-transmission line, and to transmit the target laser into the interior of the target cell through the second sub-transmission line.

13. The battery thermal runaway triggering system according to claim 12, characterized in that, A collimation adapter is also provided between the first sub-transmission line and the second sub-transmission line; The laser device is specifically used to transmit the target laser to the collimation adapter via the first sub-transmission line, to focus the target laser to obtain a focused target laser, to transmit the focused target laser to the second sub-transmission line, and to transmit the focused target laser into the interior of the target cell via the second sub-transmission line.

14. The battery thermal runaway triggering system according to any one of claims 9-11, characterized in that, An insulating layer is provided on the outer surface of the laser transmission line.

15. The battery thermal runaway triggering system according to any one of claims 9-11, characterized in that, Temperature acquisition components are provided on the top cover of the target battery cell and on the top covers of each battery cell adjacent to the target battery cell in the target battery pack. The temperature acquisition component is used to acquire the temperature of the corresponding battery cell.

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