Battery module and battery pack

Abstract

The utility model relates to a battery module and a battery pack, and relates to the technical field of power batteries. The battery module comprises a battery cell assembly, a fire extinguishing device and a trigger module, the battery cell assembly comprises a plurality of battery cells which are arranged in sequence; the fire extinguishing device is arranged at the end of the cell assembly. The trigger module comprises a temperature sensing wire, and the temperature sensing wire is arranged at the end, where the pole column is located, of the battery cell assembly and is close to the anti-explosion valve of the battery cell. Wherein the temperature sensing wire is connected to the fire extinguishing device so as to trigger the fire extinguishing device. According to the battery module provided by the invention, the safety of the battery can be improved in the application process of the ternary battery so as to cope with a higher thermal runaway risk caused by the ternary battery.

Description

Technical Field

[0001] This application relates to the field of power battery technology, specifically to a battery module and battery pack. Background Technology

[0002] With the gradual development of new energy technologies, more and more vehicles are using lithium batteries as their power source. The resulting demand for longer driving range is also driving up the requirements for the capacity of power batteries.

[0003] In existing technologies, to improve the energy density of power batteries and thus increase battery capacity without changing the volume, ternary lithium batteries are sometimes being used to replace traditional lithium iron phosphate batteries. Ternary lithium batteries have a higher energy density, resulting in a larger capacity for the same volume and providing longer battery life for devices.

[0004] However, ternary batteries are chemically more reactive and typically begin to burn at around 200°C, thus posing a higher risk of thermal runaway compared to traditional lithium iron phosphate batteries.

[0005] Therefore, there is an urgent need to provide a battery module that can improve battery safety during the application of ternary lithium batteries in order to cope with the higher risk of thermal runaway brought about by ternary lithium batteries. Utility Model Content

[0006] The purpose of this application is to provide a battery module and battery pack that can improve battery safety during the application of ternary lithium batteries in order to cope with the higher risk of thermal runaway brought about by ternary lithium batteries.

[0007] To achieve the above objectives, in a first aspect, this application provides a battery module. The battery module includes a cell assembly, a fire extinguishing device, and a triggering module. The cell assembly includes multiple cells arranged sequentially. The fire extinguishing device is disposed at the end of the cell assembly. The triggering module includes a temperature sensing wire disposed at the end of the cell assembly where the upper terminal is located, and the temperature sensing wire is close to the explosion-proof valve of the cell. The temperature sensing wire is connected to the fire extinguishing device to trigger the fire extinguishing device.

[0008] Based on the embodiments described above, when the battery module is specifically configured as a ternary lithium battery, it is more prone to thermal runaway compared to traditional lithium iron phosphate batteries. During battery assembly, multiple cells are arranged sequentially to form a cell assembly. By incorporating a fire extinguishing device and a triggering module, when one or more cells experience thermal runaway, the explosion-proof valve on the cell will rupture. The high-temperature fumes and other high-temperature substances ejected from the explosion-proof valve will rapidly transfer heat to the temperature sensing wire, causing it to ignite. The ignited temperature sensing wire then transmits heat to the fire extinguishing device, triggering its detonation and cooling the fire. Specifically, the fire extinguishing device can be filled with a certain amount of aerosol or similar extinguishing agent via compression. After the fire extinguishing device is detonated, the aerosol or similar extinguishing agent is rapidly ejected, thereby cooling and flame-retarding the interior of the battery pack, reducing the possibility of further escalation of thermal runaway and improving the overall safety of the battery module.

[0009] In some embodiments, two fire extinguishing devices are provided, located at both ends of the battery cell assembly along a first direction, with the two ends of the temperature sensing wire connected to the two ends of the two fire extinguishing devices respectively. The first direction corresponds to the arrangement direction of the battery cells.

[0010] Based on the embodiments described above, by setting two fire extinguishing devices, each located at one end of the battery cell assembly, the ignition of the temperature sensing wire can trigger both fire extinguishing devices, increasing the coverage area inside the battery box and improving the cooling and flame-retardant effects. Furthermore, when the temperature sensing wire is ignited by a battery cell, the fire extinguishing device closer to that cell will be ignited first, thereby improving the timeliness of the fire extinguishing device triggering, shortening the response time, and further enhancing the safety of the battery module.

[0011] In some embodiments, the battery cell assembly has end plates at both ends along the first direction, and the fire extinguishing device is disposed on the side of the end plate away from the battery cell assembly.

[0012] Based on the embodiments described above, by providing end plates, the battery cells can be clamped from both ends respectively, thereby improving the overall fixation effect of the battery cell assembly. Furthermore, by placing the fire extinguishing device on the side of the end plate away from the battery cell assembly, it can provide protection when the fire extinguishing device is detonated, preventing damage to the battery cells at the ends during the detonation process.

[0013] In some embodiments, a first flame-retardant sleeve is provided outside the temperature sensing wire, and a gap is provided between the temperature sensing wire and the first flame-retardant sleeve.

[0014] Based on the above embodiments of this application, by providing a first flame-retardant sleeve outside the temperature-sensing wire, which can be specifically made of a fire-resistant and heat-insulating material, it is possible to prevent the temperature-sensing wire from igniting or heating other components during the ignition process. Simultaneously, by providing a certain gap between the temperature-sensing wire and the first flame-retardant sleeve, the impact on the combustion process of the temperature-sensing wire can be reduced, and the possibility of the temperature-sensing wire extinguishing midway and affecting the triggering process can be prevented to some extent.

[0015] In some embodiments, the battery module further includes plastic packing straps, which are fitted over the outside of the cell assembly to secure the cell assembly.

[0016] Based on the embodiments described above, by providing plastic strapping around the battery cell assembly, the battery cell assembly can be tightly secured externally, thereby enhancing the fixing effect between the individual battery cells. Specifically, multiple plastic strapping strips can be used, ensuring a more even distribution of force on the battery cells while maintaining the fixing effect.

[0017] In some embodiments, the temperature-sensing wire extends to and abuts against the plastic strapping to ignite the plastic strapping.

[0018] Based on the above embodiments of this application, by contacting the temperature sensing wire with the plastic strapping, when the temperature sensing wire is ignited, the plastic strapping will be ignited when the temperature sensing wire burns to the position of the plastic strapping, thereby causing the plastic strapping to break, thereby releasing the pre-tightening force when the battery cell experiences thermal runaway, and to a certain extent avoiding the pre-tightening force from further aggravating the thermal runaway of the battery cell assembly.

[0019] In some embodiments, a winding post is provided on the plastic strapping, the winding post is fixed on the plastic strapping, and the temperature sensing wire is partially wound around the winding post.

[0020] Based on the embodiments described above, by setting a winding post on the plastic strapping and winding the temperature sensing wire around the winding post, the wiring path of the temperature sensing wire can be controlled, making the wiring path more stable and controllable. Furthermore, it ensures stable contact between the temperature sensing wire and the plastic strapping, allowing the temperature sensing wire to reliably ignite the plastic strapping to release the pre-tension.

[0021] In some embodiments, a sealing cap is fastened to the plastic strapping to form a sealed cavity, and a temperature sensing wire passes through the sealed cavity and abuts against the plastic strapping. The sealing cap has ventilation holes. A second flame-retardant sleeve is fitted over the portion of the plastic strapping excluding the sealed cavity.

[0022] Based on the embodiments described above, by forming a closed cavity and opening ventilation holes, the combustion rate of the plastic strapping within the closed cavity is controlled, keeping the plastic strapping in a smoldering state as much as possible and preventing open flames. Furthermore, by providing a second flame-retardant sleeve on the portion of the plastic strapping outside the closed cavity, specifically made of a heat-resistant and heat-insulating material, the breakage point of the plastic strapping is stably confined within the closed cavity, ensuring stability when the preload is released. On the other hand, it also prevents the combustion of other parts of the plastic strapping from transferring heat to other components, thereby preventing secondary fires.

[0023] In some embodiments, a buffer heat insulation pad is provided between any two adjacent cells.

[0024] Based on the above embodiments of this application, by setting a buffer heat insulation pad between any two adjacent battery cells, on the one hand, it can buffer and reserve expansion space during battery cell assembly, and on the other hand, it can block heat when the battery cell experiences thermal runaway, thus avoiding the spread of thermal runaway to a certain extent.

[0025] According to a second aspect of this application, a battery pack is provided, the battery pack including a housing and the aforementioned battery module. A receiving cavity is formed inside the housing, and the battery module is disposed within the receiving cavity.

[0026] Based on the above embodiments of this application, the battery pack provided by this application includes the aforementioned battery module. With the above configuration, the battery module is entirely housed within the receiving cavity. When thermal runaway occurs in a battery cell, the high-temperature smoke and combustible materials ejected from the cell's explosion-proof valve ignite the temperature sensing wire, which in turn ignites the fire extinguishing device, causing it to explode. The extinguishing agent inside the device is then ejected into the receiving cavity, achieving a cooling and flame-retardant effect, thereby mitigating or even directly preventing the thermal runaway process of the battery cell. Simultaneously, during the process of the temperature sensing wire igniting the fire extinguishing device, the wire also ignites the plastic strapping, causing it to burn and break, thus releasing the pre-tension force and preventing the cells from being excessively tightly bound, which could exacerbate the thermal runaway process. In summary, through the relevant configuration of the battery module, in the event of thermal runaway within the battery pack, fire extinguishing and pre-tension force release can be achieved, preventing further escalation of the thermal runaway process to a certain extent, thereby improving the overall safety of the battery pack.

[0027] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description

[0028] The accompanying drawings are provided to further illustrate the present application and form part of the specification. They are used together with the following detailed description to explain the present application, but do not constitute a limitation thereof. In the drawings:

[0029] Figure 1 This is a schematic diagram of the battery module provided in the embodiments of this application.

[0030] Figure 2 This is another structural schematic diagram of the battery module provided in the embodiments of this application.

[0031] Figure 3 This is a plan view of the battery module provided in the embodiments of this application.

[0032] Figure 4 This is a schematic diagram of the temperature sensing wire in the battery module provided in the embodiments of this application.

[0033] Figure 5 yes Figure 2 An enlarged schematic diagram of part A in the middle.

[0034] Figure 6 yes Figure 3 Enlarged schematic diagram of part B.

[0035] Explanation of reference numerals in the attached figures

[0036] 1. Battery cell; 2. Fire extinguishing device; 3. Temperature sensing wire; 31. First flame-retardant sleeve; 4. End plate; 5. Plastic packing strap; 51. Winding post; 52. Sealing cover; 53. Vent hole; 54. Second flame-retardant sleeve; 55. Buffer and heat insulation pad; 6. Connecting plate; 7. Data collection harness; 8. Explosion-proof valve. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0038] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0039] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0040] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0041] In the description of this application, it should be noted that, unless otherwise stated, the terms "inner," "outer," etc., indicating the orientation or positional relationship are 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 describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0042] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "setup" and "connection" 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 direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0043] In existing technologies, to improve the energy density of power batteries and thus increase battery capacity without changing the volume, ternary lithium batteries are sometimes being used to replace traditional lithium iron phosphate batteries. This involves replacing the positive electrode material of the battery with ternary materials such as nickel, cobalt, and manganese, or nickel, cobalt, and aluminum. Ternary lithium batteries have a higher energy density, typically reaching around 200 Wh / kg, a significant improvement over the approximately 110 Wh / kg energy density of traditional lithium iron phosphate batteries. Therefore, they offer greater battery capacity within the same volume, providing longer driving range for devices.

[0044] However, ternary batteries are chemically more reactive and typically begin to burn at around 200°C, thus posing a higher risk of thermal runaway compared to traditional lithium iron phosphate batteries.

[0045] To address the aforementioned problems in the prior art, according to a first aspect of this application, an embodiment of this application provides a battery module. (Reference) Figures 1 to 6 As shown, the battery module includes a cell assembly, a fire extinguishing device 2, and a triggering module. The cell assembly includes multiple cells 1 arranged sequentially. The fire extinguishing device 2 is located at the end of the cell assembly. The triggering module includes a temperature sensing wire 3, which is located at the end of the cell assembly where the upper terminal is located, and is close to the explosion-proof valve 8 of the cell 1. The temperature sensing wire 3 is connected to the fire extinguishing device 2 to trigger the fire extinguishing device 2.

[0046] Based on the above embodiments of this application, when the battery module is specifically configured as a ternary lithium battery, it is more prone to thermal runaway compared to traditional lithium iron phosphate batteries. During battery assembly, multiple cells 1 are arranged sequentially to form a cell assembly. By setting up a fire extinguishing device 2 and a triggering module, when one or more cells 1 experience thermal runaway, the explosion-proof valve 8 on the cell 1 will rupture. At this time, the high-temperature smoke and other high-temperature substances ejected from the explosion-proof valve 8 will rapidly transfer heat to the temperature sensing wire 3, causing the temperature sensing wire 3 to ignite. The ignited temperature sensing wire 3 is then transferred to the fire extinguishing device 2, thereby detonating the fire extinguishing device 2 to cool and extinguish the fire.

[0047] Specifically, the fire extinguishing device 2 can be filled with a certain amount of fire extinguishing agent, such as aerosol, through compression. After the fire extinguishing device 2 is detonated, the fire extinguishing agent, such as aerosol, is rapidly sprayed out, thereby cooling and flame-retarding the inside of the battery box, reducing the possibility of further aggravation of the thermal runaway of the battery cell 1, and improving the overall safety of the battery module.

[0048] Furthermore, when the extinguishing agent in the fire extinguishing device 2 is specifically selected as an aerosol extinguishing agent, after the fire extinguishing device 2 explodes, the aerosol is sprayed into the box. At this time, the particles in the aerosol absorb a large amount of heat in the high-temperature environment, and then undergo physical endothermic processes such as vaporization and thermal melting, thereby reducing the overall temperature inside the box, thus inhibiting the thermal runaway process of cell 1 and slowing down the thermal runaway rate. At the same time, the chemical substances in the aerosol can react with free radicals and active substances in the flame, reducing the combustion free radicals while consuming active groups, thereby interrupting the chain reaction of the combustion reaction and achieving the purpose of extinguishing the fire. In summary, based on the above properties, the aerosol extinguishing agent can quickly reduce the temperature and extinguish the fire after being sprayed into the box, so as to prevent the further aggravation of thermal runaway and improve the overall safety of the battery module.

[0049] refer to Figure 1 As shown, during the specific assembly of the battery module, multiple battery cells 1 are arranged sequentially to form a battery cell assembly. Each battery cell 1 is provided with a positive terminal and a negative terminal. Adjacent battery cells 1 are connected in series by connecting the terminals through a tab. At the same time, an explosion-proof valve 8 is provided between the positive terminal and the negative terminal on the battery cell 1 to release pressure in the event of thermal runaway inside the battery cell 1.

[0050] The temperature sensing wire 3 is installed along the arrangement direction of the battery cell 1 and is close to the explosion-proof valve 8. This allows the temperature sensing wire 3 to be quickly and stably ignited when the explosion-proof valve 8 bursts and releases pressure after the battery cell 1 has thermal runaway, thereby triggering the fire extinguishing device 2.

[0051] Furthermore, it should be noted that this application does not limit the specific material of the temperature sensing wire 3. In actual use, any suitable material can be selected. The material selected should meet the requirements of being able to ignite quickly and burn stably. The specific material can be set according to the actual situation. This application does not impose any specific restrictions on this.

[0052] Meanwhile, the specific triggering structure between the temperature sensing wire 3 and the fire extinguishing device 2 can be any suitable structure from the existing technology. For example, a metal alloy material or a thermistor can be installed inside the fire extinguishing device 2. When the temperature sensing wire 3 burns to the position of the fire extinguishing device 2, the metal alloy or thermistor undergoes a phase change due to heat, which leads to a sharp increase in internal pressure of the fire extinguishing device 2, eventually causing it to burst and release the extinguishing agent. The specific configuration can be made according to the actual situation, and this application does not impose any specific restrictions on it.

[0053] In some embodiments of this application, two fire extinguishing devices 2 may be provided, with the two fire extinguishing devices 2 disposed at both ends of the battery cell assembly along a first direction, and the two ends of the temperature sensing wire 3 respectively connected to the two ends of the two fire extinguishing devices 2. The first direction corresponds to the arrangement direction of the battery cells 1.

[0054] Based on the above embodiments of this application, by setting two fire extinguishing devices 2, which are respectively located at both ends of the battery cell assembly, the ignition of the temperature sensing wire 3 can trigger both fire extinguishing devices 2, thereby increasing the coverage area inside the battery box and improving the cooling and flame-retardant effect. On the other hand, after the temperature sensing wire 3 is ignited by a battery cell 1, it will first ignite the fire extinguishing device 2 closer to that battery cell 1, thereby improving the timeliness of the triggering of the fire extinguishing device 2, shortening the response time of the fire extinguishing device 2, and further improving the safety of the battery module.

[0055] Specifically, taking a configuration of five battery cells 1 arranged from left to right as an example, two fire extinguishing devices 2 are respectively located at opposite ends of the battery cell assembly along the left and right directions. When the second battery cell 1 from the left experiences thermal runaway, the flammable substance ejected from the explosion-proof valve 8 of the battery cell 1 ignites the temperature sensing wire 3, causing it to burn simultaneously to both sides. During this process, because the battery cell 1 experiencing thermal runaway is closer to the fire extinguishing device 2 on the left, the path from the ignition point of the temperature sensing wire 3 to the fire extinguishing device 2 on the left is shorter, causing the fire extinguishing device 2 on the left to trigger first. Similarly, when the battery cell 1 closer to the right experiences thermal runaway, the fire extinguishing device 2 on the right will trigger first. Compared to using only a single fire extinguishing device 2, this method shortens the response time of the fire extinguishing device 2.

[0056] refer to Figure 4 As shown in some embodiments of this application, a first flame-retardant sleeve 31 may be fitted over the outside of the temperature sensing wire 3, and a gap is provided between the temperature sensing wire 3 and the first flame-retardant sleeve 31.

[0057] Based on the above embodiments of this application, by providing a first flame-retardant sleeve 31 outside the temperature sensing wire 3, the first flame-retardant sleeve 31 can be specifically made of a fire-resistant and heat-insulating material, thereby preventing the temperature sensing wire 3 from igniting or heating other components during the ignition process. Simultaneously, by providing a certain gap between the temperature sensing wire 3 and the first flame-retardant sleeve 31, the impact on the combustion process of the temperature sensing wire 3 can be reduced, and the possibility of the temperature sensing wire 3 extinguishing midway and affecting the triggering process can be prevented to some extent.

[0058] Specifically, the first flame-retardant sleeve 31 can be made of any suitable material, such as glass fiber or alumina fiber, during the specific processing. The good fire resistance and heat insulation effect of the above materials are used to wrap and protect the temperature sensing wire 3, so as to prevent the temperature sensing wire 3 from igniting other components.

[0059] Furthermore, at the position where the temperature sensing wire 3 is close to each explosion-proof valve 8, the first flame-retardant sleeve 31 can be provided with a corresponding clearance groove so that the temperature sensing wire 3 is exposed at that position, thereby enabling the temperature sensing wire 3 to be quickly and stably ignited when the explosion-proof valve 8 bursts, thereby triggering the fire extinguishing device 2.

[0060] refer to Figures 1 to 5 As shown in some embodiments of this application, the battery module may further include a plastic packing strap 5, which is sleeved on the outside of the cell assembly to fix the cell assembly.

[0061] Based on the above embodiments of this application, by providing plastic strapping 5 on the outside of the battery cell assembly, it is possible to tighten and fix the battery cell assembly externally, thereby enhancing the fixing effect between each battery cell 1. Specifically, multiple plastic strapping 5s can be provided, which ensures the fixing effect while making the force on the battery cell 1 more uniform.

[0062] Further, refer to Figure 5 As shown, in some embodiments of this application, the temperature sensing wire 3 extends to the position of the plastic strapping 5 and abuts against the plastic strapping 5 to ignite the plastic strapping 5.

[0063] Based on the above embodiments of this application, by bringing the temperature sensing wire 3 into contact with the plastic strapping 5, when the temperature sensing wire 3 is ignited, the temperature sensing wire 3 will ignite the plastic strapping 5 when it burns to the position of the plastic strapping 5, thereby causing the plastic strapping 5 to break, thereby releasing the pre-tightening force when the battery cell 1 experiences thermal runaway, and to a certain extent avoiding the pre-tightening force from further aggravating the thermal runaway of the battery cell assembly.

[0064] Specifically, in practical use, the plastic strapping 5 can be made of materials such as plastic or rubber. These materials not only have a certain degree of elasticity, which can provide a certain buffering effect during the pre-tightening of the battery cell 1 during assembly, preventing damage to the battery cell 1 during binding and fixing, but also can continuously provide pre-tightening force in the subsequent process. At the same time, the above-mentioned materials have good flammability and can be quickly ignited by the temperature sensing wire 3. After being ignited, they can burn and break quickly, making the release of pre-tightening force stable and rapid, thus enabling a rapid response when the battery cell 1 experiences thermal runaway.

[0065] refer to Figure 5 As shown in some embodiments of this application, a winding post 51 is provided on the plastic strapping 5, the winding post 51 is fixed on the plastic strapping 5, and the temperature sensing wire 3 is partially wound around the winding post 51.

[0066] Based on the above embodiments of this application, by setting a winding post 51 on the plastic strapping 5 and winding the temperature sensing wire 3 partially around the winding post 51, the wiring path of the temperature sensing wire 3 can be controlled, making the wiring path of the temperature sensing wire 3 more stable and controllable. On the other hand, it can also ensure stable contact between the temperature sensing wire 3 and the plastic strapping 5, so that the temperature sensing wire 3 can stably ignite the plastic strapping to release the pre-tension force.

[0067] Specifically, by setting up the winding post 51, the temperature sensing wire 3 can be wound multiple times on the winding post 51. Through multiple turns, when the temperature sensing wire 3 burns, the winding post 51 can heat up rapidly, thereby igniting the plastic strapping 5, causing the plastic strapping 5 to break and release the pre-tension force. At the same time, the winding post 51 should be made of a fire-resistant material with good thermal conductivity, such as metal. The specific material can be selected according to the actual situation, and this application does not impose specific restrictions on it.

[0068] refer to Figure 5 As shown in some embodiments of this application, a sealing cap 52 is fastened to the plastic strapping 5 to form a sealed cavity, and a temperature sensing wire 3 passes through the sealed cavity and abuts against the plastic strapping 5. A vent hole 53 is provided on the sealing cap 52. A second flame-retardant sleeve 54 is fitted on the portion of the plastic strapping 5 other than the sealed cavity.

[0069] Based on the embodiments described above, by forming a closed cavity and opening ventilation holes 53, the burning rate of the plastic strapping 5 within the closed cavity is controlled, ensuring that the plastic strapping 5 remains in a smoldering state as much as possible, thus preventing open flames. Furthermore, by providing a second flame-retardant sleeve 54 on the portion of the plastic strapping outside the closed cavity, specifically made of a heat-resistant and heat-insulating material, the breakage point of the plastic strapping is stably confined within the closed cavity, ensuring stability during pre-tension release. On the other hand, it also prevents the burning of other parts of the plastic strapping from transferring heat to other components, thereby preventing secondary fires.

[0070] Specifically, the second flame-retardant sleeve 54 can also be made of materials such as glass fiber or alumina fiber, just like the first flame-retardant sleeve 31. The good fire resistance and heat insulation of the above materials are used to wrap and protect the temperature sensing wire 3, so as to prevent the plastic strapping 5 from igniting other components.

[0071] Furthermore, in some other embodiments of this application, in order to ensure that the temperature sensing wire 3 can reliably ignite the plastic strapping 5, a certain amount of flammable material, such as cotton or paper, can be filled around the winding post 51 to ignite the plastic strapping 5.

[0072] refer to Figure 1 As shown in some embodiments of this application, end plates 4 are respectively provided at both ends of the battery cell assembly along the first direction, and the fire extinguishing device 2 is provided on the side of the end plate 4 away from the battery cell assembly.

[0073] Based on the embodiments described above, by providing end plates 4, the battery cells 1 can be clamped from both ends respectively, thereby improving the overall fixation effect of the battery cell assembly. Furthermore, by placing the fire extinguishing device 2 on the side of the end plate 4 away from the battery cell assembly, it can provide protection when the fire extinguishing device 2 is detonated, preventing damage to the battery cells 1 at the ends during the detonation process.

[0074] Furthermore, it should be noted that the battery module in this application is not limited to the above structure. In some embodiments of this application, the battery module may also include a vacuum forming plate, a data acquisition harness 7, and other structures. The vacuum forming plate serves as the substrate for the integrated busbar and is positioned on the upper end of the battery module. It also has clearance holes at the locations of the terminals of the battery cell 1 and the connecting plate 6. The data acquisition harness 7 is connected to the connecting plate 6 to collect data such as current and temperature during battery module operation. In this case, the temperature sensing wire 3 and its external first flame-retardant sleeve 31 can be fixed to the vacuum forming plate and other structures using adhesives or other methods during installation to prevent the temperature sensing wire 3 from moving and affecting the triggering effect during battery module use.

[0075] Furthermore, the structure described in this application is not limited to ternary lithium battery structures. When the battery module is specifically configured as a lithium iron phosphate battery or other types of batteries, the above structure can also be used to quickly extinguish the fire in the event of thermal runaway of the battery module, while releasing the pre-tightening force to prevent the thermal runaway of the battery module from further aggravating, thereby improving the overall safety of the battery module.

[0076] refer to Figure 1 As shown in some embodiments of this application, a buffer heat insulation pad 55 may be provided between any two adjacent battery cells 1.

[0077] Based on the above embodiments of this application, by setting a buffer heat insulation pad 55 between any two adjacent battery cells 1, on the one hand, it can buffer and reserve expansion space when the battery cells 1 are assembled, and on the other hand, it can block heat when the battery cells 1 experience thermal runaway, thereby avoiding the spread of thermal runaway to a certain extent.

[0078] Specifically, in existing technologies, buffer foam is typically placed between the battery cells 1 to provide cushioning during the assembly of the battery cells 1 and to allow for expansion space. However, by replacing the buffer foam with a buffer heat insulation pad 55, materials such as aerogel can be selected in specific applications. This allows for both expansion space and heat insulation, preventing the spread of thermal runaway.

[0079] According to a second aspect of this application, a battery pack is provided, the battery pack including a housing and the aforementioned battery module. A receiving cavity is formed inside the housing, and the battery module is disposed within the receiving cavity.

[0080] Based on the above embodiments of this application, the battery pack provided by this application includes the aforementioned battery module. With the above configuration, the battery module is entirely housed within the receiving cavity. When cell 1 experiences thermal runaway, the high-temperature smoke and combustible materials ejected from the explosion-proof valve 8 of cell 1 ignite the temperature sensing wire 3. Subsequently, the temperature sensing wire 3 ignites the fire extinguishing device 2, causing the fire extinguishing device 2 to explode. The extinguishing agent inside the fire extinguishing device 2 is then ejected into the receiving cavity, achieving a cooling and flame-retardant effect, thereby mitigating or even directly preventing the thermal runaway process of cell 1.

[0081] Simultaneously, during the process of the temperature sensing wire 3 igniting the fire extinguishing device 2, the temperature sensing wire 3 will also ignite the plastic strapping, causing the plastic strapping 5 to burn and break, thereby releasing the pre-tension force and preventing the thermal runaway process from being exacerbated by excessively tight binding between the battery cells 1. In summary, through the relevant settings of the battery module, in the event of thermal runaway inside the battery pack, fire extinguishing and pre-tension force release can be achieved, which to a certain extent prevents the further escalation of the thermal runaway process, thereby improving the overall safety of the battery pack.

[0082] Furthermore, it should be noted that the battery pack in this application is not limited to the components mentioned above. In some other embodiments of this application, the battery pack may also include a liquid cooling plate, which is disposed at the bottom of the battery module and in direct contact with the battery cell 1, for heat dissipation and cooling of the battery cell 1, thereby reducing the possibility of thermal runaway of the battery module.

[0083] The preferred embodiments of this application have been described in detail above with reference to the accompanying drawings. However, this application is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this application, various simple modifications can be made to the technical solution of this application, and these simple modifications all fall within the protection scope of this application.

[0084] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this application will not describe the various possible combinations separately.

[0085] Furthermore, various different implementations of this application can be combined in any way, as long as they do not violate the spirit of this application, they should also be regarded as the content disclosed in this application.

Claims

1. A battery module, characterized by, The battery module comprises: a cell assembly comprising a plurality of cells, the plurality of cells being arranged in sequence; a fire extinguishing device arranged at an end of the cell assembly; a triggering module comprising a temperature sensing wire, the temperature sensing wire being arranged at an end of the cell assembly where a post is located, and the temperature sensing wire being close to an explosion-proof valve of the cell; wherein the temperature sensing wire is connected to the fire extinguishing device to trigger the fire extinguishing device.

2. The battery module of claim 1, wherein, The fire extinguishing device is provided with two, and the two fire extinguishing devices are arranged at the two ends of the cell assembly along a first direction, and the two ends of the temperature sensing wire are respectively connected to the two ends of the fire extinguishing device. The first direction corresponds to the arrangement direction of the cell.

3. The battery module of claim 2, wherein, The cell assembly is respectively provided with an end plate at the two ends along the first direction, and the fire extinguishing device is arranged on the side of the end plate away from the cell assembly.

4. The battery module of claim 1, wherein, The temperature sensing wire is externally sleeved with a first fire-retardant sleeve, and a gap is arranged between the temperature sensing wire and the first fire-retardant sleeve.

5. The battery module of claim 1, wherein, The battery module further comprises a plastic packing belt, and the plastic packing belt is sleeved outside the cell assembly to fix the cell assembly.

6. The battery module of claim 5, wherein, The temperature sensing wire extends to the position of the plastic packing belt and abuts against the plastic packing belt to ignite the plastic packing belt.

7. The battery module of claim 6, wherein, The plastic packing belt is provided with a winding post fixed thereon, and the temperature sensing wire is partially wound on the winding post.

8. The battery module of any one of claims 5-7, wherein, The plastic packing belt is provided with a closure cover to form a closed cavity, and the temperature sensing wire is arranged in the closed cavity and abuts against the plastic packing belt, and the closure cover is provided with a ventilation hole. The part of the plastic packing belt except the closed cavity is sleeved with a second fire-retardant sleeve.

9. The battery module of claim 1, wherein, A buffer heat insulation pad is arranged between any two adjacent cells.

10. A battery pack, characterized by, The battery pack comprises: a box body, an accommodating cavity is formed in the box body; and The battery module according to any one of claims 1-9 is arranged in the accommodating cavity.

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