Battery pack

Abstract

This utility model discloses a battery pack comprising multiple modules, each module including multiple battery cells stacked along a first direction, each battery cell having a tab, and multiple tabs of the same module arranged along the first direction to form a tab group; and each tab group is correspondingly provided with at least one fire extinguishing mechanism. This utility model improves fire extinguishing accuracy and reduces the impact on areas where thermal runaway has not occurred.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery pack. Background Technology

[0002] As the market places increasing emphasis on the safety of new energy vehicles, the issue of battery thermal runaway protection is becoming increasingly important. Existing fire suppression systems have limitations: when a module within the battery pack experiences thermal runaway, the system often sprays extinguishing agent throughout the entire battery pack, making it difficult to precisely target the runaway area. This results in low extinguishing agent utilization and may also cause unnecessary damage to areas where thermal runaway has not yet occurred. Utility Model Content

[0003] Currently, when a module within a battery pack experiences thermal runaway, the fire extinguishing mechanism sprays extinguishing agent across the entire battery pack, resulting in poor accuracy. To overcome these shortcomings, the purpose of this invention is to provide a battery pack that improves fire extinguishing accuracy and reduces the impact on areas where thermal runaway has not occurred.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] This utility model provides a battery pack, including multiple modules, each module including multiple cells stacked along a first direction, each cell having a tab, multiple tabs of the same module arranged along the first direction to form a tab group; and each tab group is provided with at least one fire extinguishing mechanism.

[0006] In one embodiment, the system further includes a lid and a housing, with multiple fire extinguishing mechanisms integrated inside the lid and multiple modules placed inside the housing.

[0007] In one embodiment, the inner wall of the box cover is provided with a plurality of mounting slots spaced apart along the second direction, the number of mounting slots being the same as the number of fire extinguishing mechanisms, and one fire extinguishing mechanism being installed in one mounting slot.

[0008] In one embodiment, the fire extinguishing mechanism is a fire extinguishing box, the side of the fire extinguishing box facing the module is a spraying surface, a lead wire is installed on the spraying surface corresponding to the position of the electrode assembly, and multiple spraying ports are also opened on the spraying surface; the fire extinguishing box is filled with fire extinguishing agent.

[0009] In one embodiment, the lead wire extends along a first direction, and the length of the lead wire is greater than the length of the corresponding tab assembly.

[0010] In one embodiment, a plurality of the ejection ports are arranged sequentially at intervals along a first direction and are aligned with the positions of the corresponding electrode groups.

[0011] In one embodiment, the ejection regions of the plurality of ejection ports cover all the electrodes corresponding to the electrode group in the first direction.

[0012] In one embodiment, the ejection surface is provided with a connector and a plurality of retaining sleeves, the plurality of retaining sleeves are arranged along a first direction and the connector is located at the end of the arrangement path, the connector is provided with a through hole communicating with the interior of the fire extinguishing box, the lead wire is passed through the plurality of retaining sleeves and one end of the lead wire passes through the through hole and is inserted into the interior of the fire extinguishing box.

[0013] In one embodiment, a bursting diaphragm is provided at the nozzle.

[0014] In one embodiment, the extinguishing agent is an aerosol extinguishing agent or a perfluorohexanone extinguishing agent.

[0015] The beneficial effects of this utility model are as follows: the fire extinguishing mechanism is positioned correspondingly to the tab assembly. When a module in the battery pack experiences thermal runaway, the fire extinguishing mechanism corresponding to that module extinguishes the fire, achieving precise positioning and triggering of the fire extinguishing mechanism. This avoids the situation where traditional fire extinguishing mechanisms indiscriminately spray extinguishing agents throughout the entire battery pack, improving the efficiency of extinguishing agent use and reducing the impact on areas where thermal runaway has not occurred. At the same time, multiple fire extinguishing mechanisms ensure that each module is effectively protected, enhancing the comprehensiveness and reliability of the overall thermal runaway protection of the battery pack. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the battery pack structure according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram showing the connection between the electrode assembly of the module and the fire extinguishing mechanism on the box cover.

[0019] Figure 3 yes Figure 2 A schematic diagram of the structure with the lid removed.

[0020] Figure 4 This is a schematic diagram of the integrated fire extinguishing mechanism inside the box lid.

[0021] Figure 5 This is a schematic diagram of a fire extinguishing system.

[0022] Figure 6yes Figure 2 A magnified view of a portion of point A in the middle.

[0023] In the diagram: 1. Cover; 11. Mounting slot; 2. Module; 21. Battery cell; 22. Electrode assembly; 221. Electrode; 3. Housing; 4. Fire extinguishing mechanism; 41. Shell; 411. Nozzle surface; 412. Nozzle; 42. Lead wire; 43. Connector; 44. Sleeve. Detailed Implementation

[0024] The specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of this utility model. Based on the description of this utility model, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this utility model.

[0025] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0026] The terms “upper,” “lower,” “left,” “right,” “front,” “back,” “top,” “bottom,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of description and simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0027] The terms “first,” “second,” “third,” etc., are used merely to distinguish elements with similar properties, not to indicate or imply relative importance or a specific order.

[0028] The terms “include,” “comprising,” or any other variation thereof are intended to cover non-exclusive inclusion, which includes not only the elements listed but also other elements not expressly listed.

[0029] This utility model provides a battery pack, such as Figures 2 to 6 As shown, it includes multiple modules 2, each module 2 includes multiple battery cells 21 stacked along the first direction X, each battery cell 21 is provided with a tab 221, the multiple tabs 221 of the same module 2 are arranged along the first direction X to form a tab group 22, and at least one fire extinguishing mechanism 4 is provided for each tab group 22.

[0030] In this embodiment, the fire extinguishing mechanism 4 is positioned corresponding to the tab assembly 22, and one tab assembly 22 can correspond to one or more fire extinguishing mechanisms 4. When a module 2 in the battery pack experiences thermal runaway, the fire extinguishing mechanism 4 corresponding to that module 2 extinguishes the fire, achieving precise positioning and triggering of the fire extinguishing mechanism 4. This avoids the situation where the traditional fire extinguishing mechanism 4 indiscriminately sprays fire extinguishing agent onto the entire battery pack, improving the efficiency of fire extinguishing agent use and reducing the impact on areas where thermal runaway has not occurred. At the same time, multiple fire extinguishing mechanisms 4 can ensure that each module 2 is effectively protected, enhancing the comprehensiveness and reliability of the overall thermal runaway protection of the battery pack.

[0031] As one implementation method, such as Figures 1 to 6 As shown, the battery pack also includes a cover 1 and a housing 3. Multiple fire extinguishing mechanisms 4 are integrated inside the cover 1, and multiple modules 2 are placed inside the housing 3.

[0032] In this embodiment, by integrating the fire extinguishing mechanism 4 with the cover 1, the problem of existing fire extinguishing mechanisms 4 being mostly located inside the housing 3 and occupying space inside the battery pack is solved, saving internal space in the housing 3 and improving the energy density of the battery within a limited installation space.

[0033] As one implementation method, such as Figures 2 to 4 As shown, the inner wall of the cover 1 has multiple mounting slots 11 spaced apart along the second direction Y. The number of mounting slots 11 is the same as the number of fire extinguishing mechanisms 4, with one fire extinguishing mechanism 4 installed in one mounting slot 11. The mounting slots 11 provide standardized installation positions for the fire extinguishing mechanisms 4, facilitating their installation and positioning, ensuring the accuracy and consistency of their distribution, making full use of the space inside the cover 1 without occupying additional space inside the battery pack, and helping to achieve a reasonable layout of the battery pack in a limited space. At the same time, the fire extinguishing mechanisms 4 can be glued to the mounting slots 11 with adhesive, making the fire extinguishing mechanisms 4 tightly bonded to the inner wall of the cover 1, improving the stability of the fire extinguishing mechanisms 4 installation. When the battery pack is subjected to vibration, bumps, or other operating conditions, the fire extinguishing mechanisms 4 are less likely to shift, ensuring that they can function normally in the event of thermal runaway.

[0034] In this arrangement, the second direction Y intersects with the first direction X, and the second direction Y is the arrangement direction of the multiple modules 2; preferably, the first direction X and the second direction Y are perpendicular to each other. Arranging the fire extinguishing mechanism 4 based on the arrangement direction of the modules 2 can better protect against the risk of thermal runaway of the modules 2 and improve the compatibility between the fire extinguishing mechanism 4 and the modules 2; the setting of the perpendicular relationship helps to more rationally plan the position of the fire extinguishing mechanism 4 and the modules 2 within the limited battery pack space, achieve efficient use of space, and meet the need to improve the performance of the battery pack within a limited space.

[0035] As one implementation method, such as Figures 2 to 6 As shown, the fire extinguishing mechanism 4 is a fire extinguishing box. The side of the fire extinguishing box facing the module 2 is the spraying surface 411. A lead wire 42 is installed on the spraying surface 411 corresponding to the position of the tab assembly 22, and multiple spray nozzles 412 are also provided on the spraying surface 411. The fire extinguishing box is filled with fire extinguishing agent. Specifically, the fire extinguishing box includes a shell 41 with a hollow cavity. The shell 41 is filled with fire extinguishing agent to provide a material basis for fire extinguishing. The mounting groove 11 is set as a groove structure adapted to the size of the fire extinguishing box. The lead wire 42 is set on the spraying surface 411 corresponding to the position of the tab assembly 22, which can more accurately sense the temperature change near the tab assembly 22 and trigger the release of the fire extinguishing agent in the fire extinguishing box in time. The setting of multiple spray nozzles 412 can make the fire extinguishing agent sprayed from multiple positions, ensuring that the fire extinguishing agent can cover the corresponding module 2 more evenly and quickly, improving the fire extinguishing efficiency. The lead wire 42 can be a thermal wire.

[0036] As one implementation method, such as Figures 2 to 6 As shown, the lead wire 42 extends along the first direction X, and the length of the lead wire 42 is greater than the length of the corresponding tab group 22. This expands the sensing range of the lead wire 42 for temperature changes in the tab group 22, enabling more comprehensive and timely detection of temperature anomalies at different locations of the tab group 22, thus avoiding delays in fire extinguishing due to blind spots in local temperature monitoring. At the same time, the longer lead wire 42 increases its sensing area with the tab group 22, improving temperature conduction efficiency and enabling the fire extinguishing mechanism 4 to respond quickly in the early stages of thermal runaway in the tab group 22.

[0037] As one implementation method, such as Figures 2 to 6 As shown, multiple nozzles 412 are arranged sequentially at intervals along the first direction X, and aligned with the positions of the corresponding tab assemblies 22. This allows the extinguishing agent to be directly sprayed onto the tab assemblies 22 and key parts of the module 2, precisely covering areas where thermal runaway may occur, thus avoiding waste of the extinguishing agent. The orderly and spaced arrangement of the nozzles 412 creates a more uniform extinguishing agent spray coverage, ensuring effective fire protection for all parts of the module 2, and improving the uniformity and effectiveness of the fire extinguishing effect.

[0038] As one implementation method, the spraying area of ​​multiple nozzles 412 covers all the tabs 221 of the corresponding tab group 22 in the first direction X; this ensures the effective coverage area of ​​the extinguishing agent spray, can cover the tab group 22 to the maximum extent, and ensures that once the tab group 22 experiences thermal runaway, most areas can be quickly acted upon by the extinguishing agent, effectively suppressing the spread of fire; this improves the reliability of fire extinguishing and reduces the risk of fire extinguishing failure due to insufficient coverage.

[0039] As one implementation method, such as Figure 5As shown, the firing surface 411 of the fire extinguishing box is provided with a connector 43 and multiple retaining sleeves 44. The multiple retaining sleeves 44 are arranged at intervals along the first direction X, and the connector 43 is located at the end of the arrangement path. The connector 43 has a through hole (not shown) communicating with the inside of the fire extinguishing box. The lead wire 42 passes through the multiple retaining sleeves 44, and one end of the lead wire 42 passes through the through hole and is inserted into the inside of the fire extinguishing box. Among them, the annular retaining sleeves 44 protrude and are fixed on the firing surface 411, which can fix and support the lead wire 42, prevent the lead wire 42 from shifting or shaking due to vibration and other factors during the operation of the battery pack, ensure the stable connection between the lead wire 42 and the triggering structure inside the fire extinguishing box, and ensure that the lead wire 42 can reliably transmit temperature signals. The design of the connector 43 and the through hole realizes the communication between the lead wire 42 and the inside of the fire extinguishing box. At the same time, the connector 43 ensures the sealing of the inside of the fire extinguishing box and prevents the extinguishing agent from leaking. The ferrule 44 and connector 43 can be attached to the firing surface 411 of the fire extinguishing box with adhesive.

[0040] As one implementation, a rupture diaphragm (not shown) is provided at the nozzle 412. When the pressure inside the extinguishing chamber does not reach the set value, the rupture diaphragm acts as a seal to prevent extinguishing agent leakage and ensure the effectiveness of the extinguishing agent within the chamber. When the pressure inside the extinguishing chamber rises to the predetermined value due to a trigger reaction, the rupture diaphragm ruptures, allowing the extinguishing agent to be rapidly ejected from the nozzle 412, thus enabling rapid activation of the extinguishing mechanism 4 and improving the extinguishing response speed.

[0041] One implementation method involves using either aerosol extinguishing agents or perfluorohexanone extinguishing agents. Aerosol extinguishing agents are solid agents that release a large amount of high-temperature gas after a chemical reaction (combustion or decomposition). Upon cooling, this gas forms nanoscale solid particle aerosols, mixed with inert gases such as nitrogen or carbon dioxide. The solid particles in the aerosol extinguish the fire by "chemical inhibition"—adsorbing reactive free radicals such as hydroxyl radicals from the combustion reaction, thus interrupting the combustion chain reaction. Perfluorohexanone is a liquid at room temperature. Because its heat of vaporization is only 1 / 25 that of water, while its vapor pressure is 25 times that of water, these properties make it easily vaporized and exist in a gaseous state. It primarily relies on endothermic absorption to achieve its fire-extinguishing effect.

[0042] The working process of this utility model is as follows: When the operating temperature of a module 2 in the battery pack becomes abnormal, the lead wire 42 can sense and monitor the temperature of the tabs 221 on the tab assembly 22 in real time. When the temperature rises abnormally and exceeds the set temperature, the lead wire 42 ignites. During the combustion process, the lead wire 42 transfers heat to the extinguishing agent. The extinguishing agent undergoes a chemical reaction upon heating, releasing a large amount of extinguishing gas, causing the gas pressure inside the extinguishing box to rise sharply. When the internal pressure of the extinguishing box rises to the preset burst pressure value, the burst diaphragm at the nozzle 412 ruptures instantly, opening the extinguishing agent release channel. At this time, multiple nozzles 412, arranged at intervals along the first direction X and aligned with the position of the tab assembly 22, accurately spray aerosol extinguishing agent onto the module 2 with abnormally high temperature, achieving precise and rapid extinguishing of the module 2 that has experienced thermal runaway, effectively preventing the fire from spreading to other modules 2.

[0043] This invention, by having the fire extinguishing mechanism 4 positioned corresponding to the tab assembly 22, enables precise positioning and triggering of the fire extinguishing mechanism 4 when thermal runaway occurs in the cell 21 of module 2. This avoids the situation where the traditional fire extinguishing mechanism 4 indiscriminately sprays fire extinguishing agent across the entire battery pack, improving the efficiency of fire extinguishing agent use and reducing the impact on areas where thermal runaway has not occurred. Multiple fire extinguishing mechanisms 4 ensure that each module 2 is effectively protected, enhancing the comprehensiveness and reliability of the overall thermal runaway protection of the battery pack. By integrating the fire extinguishing mechanism 4 with the cover 1, space is saved, which is beneficial for increasing the energy density of the battery within a limited installation space.

[0044] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the appended claims.

Claims

1. A battery pack comprising a plurality of modules (2), characterized in that, Each module (2) includes multiple battery cells (21) stacked along a first direction (X), each battery cell (21) is provided with a tab (221), and multiple tabs (221) of the same module (2) are arranged along the first direction (X) to form a tab group (22); and at least one fire extinguishing mechanism (4) is provided for each tab group (22).

2. The battery pack of claim 1, wherein, It also includes a cover (1) and a box body (3), with multiple fire extinguishing mechanisms (4) integrated inside the cover (1) and multiple modules (2) placed inside the box body (3).

3. The battery pack of claim 2, wherein, The inner wall of the box cover (1) is provided with a plurality of mounting slots (11) spaced apart along the second direction (Y). The number of mounting slots (11) is the same as the number of fire extinguishing mechanisms (4), and one fire extinguishing mechanism (4) is installed in one mounting slot (11).

4. The battery pack of claim 1, wherein, The fire extinguishing mechanism (4) is a fire extinguishing box. The side of the fire extinguishing box facing the module (2) is a spraying surface (411). A lead wire (42) is installed on the spraying surface (411) corresponding to the position of the electrode group (22). A plurality of spraying ports (412) are also opened on the spraying surface (411). The fire extinguishing box is filled with fire extinguishing agent.

5. The battery pack of claim 4, wherein, The lead wire (42) extends along the first direction (X), and the length of the lead wire (42) is greater than the length of the corresponding tab group (22).

6. The battery pack of claim 4, wherein, The plurality of ejection ports (412) are arranged sequentially at intervals along the first direction (X) and are aligned with the positions of the corresponding electrode groups (22).

7. The battery pack of claim 4, wherein, The ejection regions of the plurality of ejection ports (412) cover all the electrodes (221) of the corresponding electrode group (22) in the first direction (X).

8. The battery pack of claim 4, wherein, The ejection surface (411) is provided with a connector (43) and a plurality of sleeves (44). The plurality of sleeves (44) are arranged along a first direction (X) and the connector (43) is located at the end of the arrangement path. The connector (43) is provided with a through hole communicating with the inside of the fire extinguishing box. The lead wire (42) is passed through the plurality of sleeves (44) and one end of the lead wire (42) passes through the through hole and is inserted into the inside of the fire extinguishing box.

9. The battery pack as described in claim 4, characterized in that, A bursting diaphragm is provided at the nozzle (412).

10. The battery pack of claim 4, wherein, The extinguishing agent is an aerosol extinguishing agent or a perfluorohexanone extinguishing agent.

Images