Battery pack shell structure and battery pack

Abstract

This application relates to the field of battery pack technology and provides a battery pack housing structure and a battery pack. The battery pack housing of this application includes a frame forming a mounting cavity, a bottom plate assembly located at the bottom of the frame, and a top plate located at the top of the frame. The top plate has an upper flow channel for coolant flow and a channel for protective medium flow, and a spray nozzle communicating with the channel is provided at the bottom of the top plate for spraying the protective medium. The bottom plate assembly has a lower flow channel for coolant flow and a connecting cavity connecting the mounting cavity to an external storage device. The battery pack housing structure described in this application can meet the heat dissipation requirements during fast charging of the battery pack while also reducing the hazards caused by thermal runaway, thereby improving the safety performance of the battery pack.

Description

Technical Field

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

[0002] With technological advancements, people are placing increasingly higher demands on battery pack charging speeds. However, high-rate fast charging inevitably leads to a significant increase in heat generation, especially in the electrode areas inside the battery cells and the battery pack itself. In traditional battery pack designs, the area near the cell cover cannot be filled with thermally conductive structural adhesive. Excessive temperatures will have a significant negative impact on battery life and safety, hindering improvements in battery pack cooling and safety performance. Utility Model Content

[0003] In view of this, this application aims to propose a battery pack housing structure to improve the cooling performance and safety performance of the battery pack.

[0004] To achieve the above objectives, the technical solution of this application is implemented as follows: A battery pack housing structure includes a frame forming a mounting cavity, a bottom plate assembly disposed at the bottom of the frame, and a top plate disposed at the top of the frame. The top plate has an upper flow channel for coolant to flow through and a channel for protective medium to flow through, and a spray nozzle communicating with the channel is provided at the bottom of the top plate. The spray nozzle is used to spray the protective medium. The base plate assembly is provided with a lower flow channel for coolant flow and a connecting cavity that connects the mounting cavity to an external storage device.

[0005] Furthermore, the channel includes a plurality of transverse channels spaced apart along the first direction on the top plate, and a longitudinal channel between one end of the plurality of transverse channels; the longitudinal channel is provided with an inlet for the protective medium to enter, and each of the transverse channels is provided with a plurality of spray nozzles spaced apart.

[0006] Furthermore, relative to the inlet, the liquid inlet and liquid outlet of the upper flow channel are located at the other end of the top plate.

[0007] Furthermore, the frame includes an annular frame body and a partition beam disposed within the frame body, the partition beam dividing the mounting cavity into multiple spaced sub-cavities; each sub-cavity can accommodate a battery module, and the top plate is provided with transverse channels at positions corresponding to the two opposite sides of each sub-cavity.

[0008] Furthermore, the base plate assembly includes a lower cooling plate and a bottom protective plate disposed at the bottom of the lower cooling plate. The lower flow channel is disposed on the lower cooling plate, and the connecting cavity is formed by the lower cooling plate and the bottom protective plate. The lower cooling plate is provided with a through hole connecting the mounting cavity and the connecting cavity, and the bottom protective plate is provided with a connecting hole connecting the connecting cavity and the external storage device.

[0009] Compared with related technologies, this application has the following advantages: (1) The battery pack housing structure described in this application has an upper flow channel for coolant flow and a channel for protective medium flow on the top plate, and an injection port for spraying protective medium connected to the channel at the bottom of the top plate. The bottom plate assembly has a lower flow channel for coolant flow and a connecting cavity for connecting the mounting cavity to the external storage device. This structure can meet the heat dissipation requirements of the battery pack during fast charging, and also reduce the hazards caused by thermal runaway, thereby improving the safety performance of the battery pack.

[0010] (2) The channel includes multiple transverse channels spaced apart on the top plate along the first direction, and a longitudinal channel between one end of the multiple transverse channels. The longitudinal channel is provided with an inlet for the protective medium to enter, and the transverse channels are provided with multiple spray nozzles spaced apart, so that the spray nozzles can cover a large area, which is beneficial to further meet the heat dissipation requirements of the battery pack and also beneficial to further reduce the hazards caused by thermal runaway.

[0011] (3) Compared with the inlet, the liquid inlet and outlet of the upper channel are located at the other end of the top plate, which can realize the isolation of the upper channel and the channel. It can realize the circulation of coolant in the upper channel, as well as the flow and spray of the protective medium, which is conducive to improving the heat dissipation capacity of the battery pack.

[0012] (4) By setting up an annular frame body and a partition beam in the frame body, the partition beam divides the mounting cavity into multiple compartments at intervals. Each compartment can accommodate the battery module, and the top plate has transverse channels on the two opposite sides of each compartment. This can reduce the waste of protective medium, which is beneficial to improving the heat dissipation effect of the battery pack and reducing the harm of battery thermal runaway. This is beneficial to improving the safety performance of the battery pack. The design of the partition beam can improve the structural strength of the battery pack and further improve the safety performance of the battery pack.

[0013] (5) By setting a lower cooling plate and a bottom guard plate at the bottom of the lower cooling plate, and the lower flow channel is set on the lower cooling plate, the connecting cavity is formed by the lower cooling plate and the bottom guard plate, and a through hole connecting the mounting cavity and the connecting cavity is set on the lower cooling plate, and a connecting hole connecting the connecting cavity and the external storage device is set on the bottom guard plate, it can improve the structural strength of the battery pack shell, and also realize the recovery of the protective medium after it is ejected, which is conducive to further improving the heat dissipation capacity of the battery pack and the control capability of battery thermal runaway.

[0014] Another objective of this application is to provide a battery pack having the battery pack housing structure as described above, a battery module disposed in a mounting cavity, and a storage device.

[0015] Furthermore, the storage device includes a storage tank storing the protective medium, an inlet pipe and an outlet pipe communicating with the storage tank, a first pumping section disposed on the inlet pipe and a second pumping section disposed on the outlet pipe; the inlet pipe is communicating with the communicating cavity, and the outlet pipe is communicating with the channel.

[0016] Furthermore, the inlet pipe and the outlet pipe are connected to the storage tank through the same connecting pipe; the connecting pipe is connected to the inlet pipe and the outlet pipe through a three-way valve.

[0017] Furthermore, the top of the battery module is connected to the top plate by a thermally conductive structural adhesive, and the injection port and the thermally conductive structural adhesive are staggered in the thickness direction of the frame.

[0018] Furthermore, the battery module includes a plurality of battery cells arranged sequentially along the second direction, and each of the battery cells is provided with a terminal post and an explosion-proof valve at both ends in the length direction; each of the battery cells has a preset space between its two ends in the length direction and the frame, and the preset space is used for the protective medium ejected from the injection port to pass through.

[0019] The storage device includes a storage tank containing a protective medium, and an inlet pipe and an outlet pipe connected to the storage tank. The inlet pipe is equipped with a first pumping unit, and the outlet pipe is equipped with a second pumping unit. The inlet pipe is connected to a connecting cavity, and the outlet pipe is connected to a channel. This enables the pumping and recovery of the protective medium, thereby achieving a cyclic supply of the protective medium. This is beneficial for further improving the heat dissipation capacity of the battery pack and the control capability for battery thermal runaway.

[0020] The inlet pipe and outlet pipe are connected to the storage tank through the same connecting pipe, and the connecting pipe is connected to the inlet pipe and the outlet pipe through a three-way valve. Its structure is simple and easy to implement, and it can also reduce space occupation and help ensure the compact size of the battery pack.

[0021] The top of the battery module is connected to the top plate by thermally conductive structural adhesive. The spray nozzle and the thermally conductive structural adhesive are staggered in the thickness direction of the frame. This enables efficient heat transfer between the battery module and the top plate, while also ensuring that the protective medium sprayed from the nozzle is not blocked by the thermally conductive structural adhesive. This is beneficial to improving the heat dissipation capacity of the battery pack and the ability to control battery thermal runaway.

[0022] By setting poles and explosion-proof valves at both ends of each cell along its length, and by providing a preset space between each cell's ends and the frame for the protective medium ejected from the nozzle, the protective medium can effectively cool the heated area of ​​the cell. At the same time, it can also reduce the high-temperature gas ejected from the explosion-proof valve when the cell experiences thermal runaway, thereby controlling heat spread and improving the safety of the battery pack.

[0023] The battery pack described in this application, by setting the battery pack housing structure as described above, can improve the heat dissipation capacity of the battery pack, and at the same time, it is also conducive to improving the control capability of the battery pack against thermal runaway, thereby improving the safety performance of the battery pack. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is an exploded view of the battery pack housing structure described in the embodiments of this application; Figure 2 This is a schematic diagram of the structure of the top plate described in an embodiment of this application; Figure 3 for Figure 2 The diagram shows the structure of the top plate from another perspective; Figure 4 This is a cross-sectional view of the top plate described in the embodiment of this application; Figure 5 This is a schematic diagram of the lower cooling plate structure described in an embodiment of this application; Figure 6 This is a cross-sectional view of the battery pack described in an embodiment of this application; Figure 7 for Figure 6 A partial structural diagram at point A in the middle; Figure 8 This is a schematic diagram of the battery module described in an embodiment of this application; Figure 9 This is a schematic diagram of the battery cell structure described in the embodiments of this application; Figure 10 This is a schematic diagram of the structure of the storage device described in the embodiments of this application; Explanation of reference numerals in the attached figures: 100. Frame; 101. Frame body; 102. Dividing beam; 103. Pre-set space; 200. Base plate assembly; 201. Lower cooling plate; 2011. Lower flow channel; 2012. Through hole; 2013. Lower liquid inlet; 2014. Lower liquid outlet; 202. Bottom guard plate; 2021. Connecting hole; 203. Connecting cavity; 204. Sealing strip; 300, Top plate; 301, Top plate flat plate; 3011, Liquid inlet; 3012, Liquid outlet; 3013, Spray nozzle; 302, Top plate flow channel plate; 3021, Upper flow channel; 3022, Channel; 30221, Transverse channel; 30222, Longitudinal channel; 30223, Inlet; 400. Battery module; 401. Battery cell; 4011. Terminal post; 4012. Explosion-proof valve; 402. Busbar; 500, Storage device; 501, Storage tank; 5011, First storage tank; 5012, Second storage tank; 502, Inlet pipe; 5021, First pumping unit; 503, Outlet pipe; 5031, Second pumping unit; 504, Connecting pipe; 505, Three-way valve; 5051, First inlet; 5052, Second inlet; 5053, Second outlet; 600, Thermally conductive structural adhesive. Detailed Implementation

[0025] To make the technical solution 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.

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0027] Furthermore, it should be noted that in the description of this application, if terms such as "upper," "lower," "inner," or "outer" appear, indicating orientation or positional relationship, these are based on the orientation or positional relationship shown in the accompanying drawings and are 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, if terms such as "first" or "second" appear, they are also used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] Furthermore, in the description of this application, unless otherwise expressly defined, the terms "installation," "connection," "joining," and "connector" 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; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application in light of the specific circumstances.

[0029] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0030] The present application will now be described in detail through exemplary embodiments. However, it should be understood that, without further description, elements, structures, and features in one embodiment may be advantageously incorporated into other embodiments.

[0031] An embodiment of the first aspect of this application provides a battery pack housing structure, which is mainly used for cooling the battery pack. Furthermore, the battery pack housing structure of this embodiment, through its innovative structural design, can improve the cooling effect on the battery pack while enhancing the ability to suppress thermal runaway of the battery pack.

[0032] In related technologies, with the development of technology, people have put forward increasingly higher requirements for the charging speed of battery packs. However, high-rate fast charging (such as 4C and above) will inevitably lead to a significant increase in heat generation, especially in the electrode area inside the battery cell and the battery plate.

[0033] In traditional battery pack designs, especially for blade-shaped batteries, the tabs and internal terminals of the cell are located on both sides of the cell cover. This area is precisely where the cell cover is welded to the casing. When the entire pack is integrated, this area cannot be filled with thermally conductive structural adhesive. Excessive temperature will have a significant negative impact on the battery's lifespan and safety, and will not be conducive to improving the battery pack's cooling performance and safety performance.

[0034] In view of this, in order to overcome the shortcomings of the related technology, the battery pack housing structure of this embodiment combines... Figures 1 to 10 As shown, the overall design includes a frame 100 with an enclosure forming an installation cavity, a base plate assembly 200 located at the bottom of the frame 100, and a top plate 300 located at the top of the frame 100.

[0035] The top plate 300 has an upper flow channel 3021 for coolant flow and a channel 3022 for protective medium flow. At the bottom of the top plate 300, there is a spray nozzle 3013 communicating with the channel 3022. The spray nozzle 3013 is used to spray the protective medium. The bottom plate assembly 200 has a lower flow channel 2011 for coolant flow and a connecting cavity 203 communicating with the mounting cavity and the external storage device 500.

[0036] Therefore, by providing an upper flow channel 3021 for coolant flow and a channel 3022 for protective medium flow on the top plate 300, and providing an injection port 3013 at the bottom of the top plate 300 that communicates with the channel 3022 for spraying protective medium, and by providing a lower flow channel 2011 for coolant flow and a connecting cavity 203 that connects the mounting cavity to the external storage device 500 on the bottom plate assembly 200, the heat dissipation requirements during fast charging of the battery pack can be met, while also reducing the hazards caused by thermal runaway, thereby improving the safety performance of the battery pack.

[0037] Based on the above general introduction, specifically, the frame 100 of this embodiment can be referred to as a battery pack frame 100 well known to those skilled in the art. In an exemplary embodiment, the top plate 300 of this embodiment is formed by stamping and connected to the frame 100 by screws. The lower cooling plate 201 of this embodiment is fixed to the frame 100 by bolts or FDS (FlowDrill Screw), thereby forming the battery pack housing structure described in this embodiment.

[0038] Furthermore, the protective medium mentioned in this embodiment may include an impregnation liquid sprayed during cooling and a fire extinguishing agent sprayed during thermal runaway. The impregnation liquid may be a fluorocarbon compound or a hydrocarbon compound (e.g., mineral oil). Since the impregnation liquid is an insulator, it can be used to cool the battery pack to achieve a cooling function. The fire extinguishing agent may be a material such as heptafluoropropane. During thermal runaway, the fire extinguishing agent can lower the gas temperature, prevent heat spread, and simultaneously consume the active functional groups in the high-temperature gas, reducing the possibility of ignition and thus significantly reducing the risk of thermal runaway.

[0039] It should be mentioned that the first direction mentioned in this embodiment is the width direction of the battery pack, the second direction mentioned in this embodiment is the length direction of the battery pack, and the third direction is the thickness direction of the battery pack.

[0040] Combination Figures 2 to 4As shown, in some exemplary embodiments, the channel 3022 includes a plurality of transverse channels 30221 spaced apart along a first direction on the top plate 300, and a longitudinal channel 30222 disposed between one end of the plurality of transverse channels 30221. The longitudinal channel 30222 is provided with an inlet 30223 for the entry of the protective medium, and each transverse channel 30221 is provided with a plurality of spray nozzles 3013 spaced apart. This arrangement allows the spray nozzles 3013 to cover a larger area, which is beneficial for further meeting the heat dissipation requirements of the battery pack and for further reducing the hazards caused by thermal runaway.

[0041] In specific implementation, the top plate 300 consists of a top plate flat plate 301 and a top plate flow channel plate 302. An inlet 3011 and an outlet 3012 are located on the top plate flat plate 301 for introducing coolant or refrigerant. A spray nozzle 3013 is also located on the top plate flat plate 301 for spraying a protective medium. The top plate flow channel plate 302 is formed by stamping and has a channel 3022 for the protective medium to flow through, and an upper flow channel 3021 for the coolant to flow through. It also has an inlet 30223 for introducing the protective medium into the channel 3022.

[0042] Continue to combine Figures 2 to 4 As shown, in some exemplary embodiments, the inlet 3011 and outlet 3012 of the upper flow channel 3021 are located at the other end of the top plate 300, relative to the inlet 30223. The advantage of this arrangement is that it enables isolation between the upper flow channel 3021 and the channel 3022, allowing for both coolant circulation in the upper flow channel 3021 and the flow and spraying of the protective medium, thus improving the heat dissipation capacity of the battery pack.

[0043] Combination Figure 1 , Figure 6 as well as Figure 7 As shown, in some exemplary embodiments, the frame 100 includes an annular frame body 101 and a partition beam 102 disposed within the frame body 101. The partition beam 102 divides the mounting cavity into a plurality of spaced sub-cavities, each of which can accommodate the battery module 400. The top plate 300 is provided with transverse channels 30221 at positions corresponding to the two opposite sides of each sub-cavity.

[0044] Thus, by setting up a ring-shaped frame body 101 and a partition beam 102 within the frame body 101, the structural strength of the battery pack can be improved, which is beneficial to improving the safety performance of the battery pack. At the same time, the transverse channels 30221 are provided on the top of the two opposite sides of each compartment, which can reduce the waste of protective medium, which is beneficial to improving the heat dissipation effect of the battery pack and reducing the harm of battery thermal runaway.

[0045] In specific implementation, the partition beam 102 of this embodiment includes a crossbeam extending along a second direction and multiple sets of longitudinal beams extending along a first direction and spaced apart. Thus, the partition beam 102 can divide the mounting cavity into multiple spaced-apart chambers, thereby preventing heat spread and improving both the heat dissipation effect of the battery pack and the control over the hazards of battery thermal runaway. It is worth mentioning that the relevant structure of the partition beam 102 in this embodiment can be referred to from related structures well known to those skilled in the art, and will not be described in detail here.

[0046] Furthermore, it is worth mentioning that in this embodiment, the top plate 300 is provided with transverse channels 30221 on both opposite sides of each compartment, that is, transverse channels 30221 are provided on both opposite sides of the battery module 400, so that the protective medium sprayed from the spray nozzle 3013 on the transverse channel 30221 can cover both sides of the battery module, thereby improving the heat dissipation effect of the battery pack and reducing the harm of battery thermal runaway.

[0047] Combination Figure 6 as well as Figure 7 As shown, in some exemplary embodiments, the base plate assembly 200 includes a lower cooling plate 201 and a bottom protective plate 202 disposed at the bottom of the lower cooling plate 201. A lower flow channel 2011 is disposed on the lower cooling plate 201, and a connecting cavity 203 is formed by the lower cooling plate 201 and the bottom protective plate 202. The lower cooling plate 201 has a through hole 2012 connecting the mounting cavity and the connecting cavity 203, and the bottom protective plate 202 has a connecting hole 2021 connecting the connecting cavity 203 and the external storage device 500.

[0048] In this way, while improving the structural strength of the battery pack casing, it is also possible to recover the protective medium after it is ejected, which is conducive to further improving the heat dissipation capacity of the battery pack and the ability to control battery thermal runaway.

[0049] In specific implementation, the connecting cavity 203 of this embodiment is formed by the lower cooling plate 201 and the bottom protective plate 202, and a sealing strip 204 is provided at the connection between the lower cooling plate 201 and the bottom protective plate 202 to achieve sealing of the connecting cavity 203. In addition, it is worth mentioning that the lower cooling plate 201 is also provided with a lower inlet 2013 and a lower outlet 2014 for coolant to enter the lower flow channel 2011. Relative to the inlet 3011 and outlet 3012 of the upper flow channel 3021, they are located at the same end of the bottom plate, thereby facilitating the arrangement of the cooling pipes.

[0050] It is worth noting that, regarding the battery pack housing structure of this embodiment, based on the above exemplary embodiments, in specific implementation, as a preferred embodiment, it is still composed of... Figures 1 to 10As shown, it may include, for example, a frame 100 with an enclosure forming an installation cavity, a base plate assembly 200 disposed at the bottom of the frame 100, and a top plate 300 disposed at the top of the frame 100.

[0051] The top plate 300 has an upper flow channel 3021 for coolant flow and a channel 3022 for protective medium flow. At the bottom of the top plate 300, there is a spray nozzle 3013 communicating with the channel 3022. The spray nozzle 3013 is used to spray the protective medium. The bottom plate assembly 200 has a lower flow channel 2011 for coolant flow and a connecting cavity 203 communicating with the mounting cavity and the external storage device 500.

[0052] The channel 3022 includes a plurality of transverse channels 30221 spaced apart along a first direction on the top plate 300, and a longitudinal channel 30222 located between one end of the plurality of transverse channels 30221. The longitudinal channel 30222 is provided with an inlet 30223 for the entry of the protective medium, and each transverse channel 30221 is provided with a plurality of spaced-apart spray nozzles 3013. Relative to the inlet 30223, the liquid inlet 3011 and liquid outlet 3012 of the upper channel 3021 are located at the other end of the top plate 300.

[0053] The frame 100 includes an annular frame body 101 and a partition beam 102 disposed within the frame body 101, which divides the mounting cavity into multiple spaced sub-cavities. Each sub-cavity can accommodate a battery module 400, and the top plate 300 has transverse channels 30221 on opposite sides of each sub-cavity. The bottom plate assembly 200 includes a lower cooling plate 201 and a bottom protective plate 202 disposed at the bottom of the lower cooling plate 201. A lower flow channel 2011 is disposed on the lower cooling plate 201. A connecting cavity 203 is formed by the lower cooling plate 201 and the bottom protective plate 202. The lower cooling plate 201 has a through hole 2012 connecting the mounting cavity and the connecting cavity 203, and the bottom protective plate 202 has a connecting hole 2021 connecting the connecting cavity 203 and the external storage device 500.

[0054] In the preferred embodiment of the battery pack housing structure described above, the specific configuration and arrangement of the top plate 300, the lower cooling plate 201, the bottom protective plate 202, etc., can still be referred to the descriptions in the above exemplary embodiments. Furthermore, in this preferred embodiment, the beneficial effects brought about by the design of the top plate 300, the lower cooling plate 201, the bottom protective plate 202, etc., can also be referred to the descriptions in the above exemplary embodiments.

[0055] The battery pack housing structure of this embodiment adopts the above design. By providing an upper flow channel 3021 for coolant flow and a channel 3022 for protective medium flow on the top plate 300, and a spray nozzle 3013 communicating with the channel 3022 for spraying protective medium at the bottom of the top plate 300, and providing a lower flow channel 2011 for coolant flow and a connecting cavity 203 connecting the mounting cavity with the external storage device 500 on the bottom plate assembly 200, it can meet the heat dissipation requirements during battery pack fast charging, and also reduce the hazards caused by thermal runaway, thereby improving the safety performance of the battery pack.

[0056] The second aspect of this application provides a battery pack, which includes the battery pack housing structure mentioned in the first aspect of the embodiment, a battery module 400 disposed in a mounting cavity, and a storage device 500.

[0057] Combination Figure 10 As shown, in some exemplary embodiments, the storage device 500 includes a storage tank 501 storing a protective medium, an inlet pipe 502 and an outlet pipe 503 communicating with the storage tank 501, a first pumping part 5021 provided on the inlet pipe 502 and a second pumping part 5031 provided on the outlet pipe 503, the inlet pipe 502 communicating with the connecting cavity 203 and the outlet pipe 503 communicating with the channel 3022.

[0058] The advantage of this setup is that it enables the pumping and recovery of the protective medium, thereby achieving a cyclical supply of the protective medium, which is beneficial to further improve the heat dissipation capacity of the battery pack and the control capability of battery thermal runaway.

[0059] In a specific implementation, the storage tank 501 of this embodiment includes a first storage tank 5011 for storing the immersion liquid and a second storage tank 5012 for storing the extinguishing agent. One end of the inlet pipe 502 is connected to the first storage tank 5011, and the other end is connected to the connecting cavity 203. A first pumping unit 5021 is disposed on the inlet pipe 502. The second storage tank 5012 is only connected to the outlet pipe 503 and not to the inlet pipe 502. Furthermore, it is worth mentioning that the storage tank 501, the first pumping unit 5021, etc., of this embodiment can all refer to storage tanks 501 and liquid pumps well known to those skilled in the art, and will not be described in detail here.

[0060] In some exemplary embodiments, the inlet pipe 502 and the outlet pipe 503 are connected to the storage tank 501 via the same connecting pipe 504, and the connecting pipe 504 is connected to the inlet pipe 502 and the outlet pipe 503 via a three-way valve 505. This design simplifies implementation, reduces space requirements, and helps maintain a compact battery pack size.

[0061] In specific implementation, the three-way valve 505 of this embodiment includes a first inlet 5051, a second inlet 5052, and a second outlet 5053. The first storage tank 5011 is connected to the inlet pipe 502 and the first inlet 5051 via a connecting pipe 504, and is connected to the outlet pipe 503 via the second outlet 5053. The second storage tank 5012 is connected to the connecting pipe 504 via the second inlet 5052, and is connected to the outlet pipe 503 via the second outlet 5053. Thus, by using the three-way valve 505 in conjunction with the second pumping unit 5031, submersion liquid or extinguishing agent can be selectively drawn from the first and second storage pipes, thereby improving both the battery pack's cooling capacity and its ability to control thermal runaway.

[0062] Combination Figure 6 as well as Figure 7 As shown, in some exemplary embodiments, the top of the battery module 400 is connected to the top plate 300 by a thermally conductive structural adhesive 600, and the injection port 3013 and the thermally conductive structural adhesive 600 are staggered in the thickness direction of the frame 100. This arrangement enables efficient heat transfer between the battery module 400 and the top plate 300, while also ensuring that the protective medium ejected from the injection port 3013 is not blocked by the thermally conductive structural adhesive 600. This improves the heat dissipation capacity of the battery pack and the ability to control battery thermal runaway.

[0063] In specific implementation, the top of the battery module 400 and the top plate 300 in this embodiment are bonded together by an upper thermally conductive structural adhesive 600, while the bottom of the battery module 400 is bonded together by a lower thermally conductive structural adhesive 600. Furthermore, it is worth mentioning that the cell 401 housing and the cell 401 cover plate in this embodiment are connected by welding, with the welds located on both sides of the battery module 400. Therefore, a blank area should be provided between the upper and lower thermally conductive structural adhesives 600 and the welds to prevent the welds from cracking due to stress, thereby further improving the safety performance of the battery pack.

[0064] Continue to combine Figure 1 , Figure 8 as well as Figure 9 As shown, in some exemplary embodiments, the battery module 400 includes a plurality of battery cells 401 arranged sequentially along a second direction. Each battery cell 401 has a terminal post 4011 and an explosion-proof valve 4012 at both ends in the length direction. Each battery cell 401 has a preset space 103 between its two ends in the length direction and the frame 100. The preset space 103 is used for the passage of the protective medium sprayed from the injection port 3013.

[0065] The advantage of this design is that it allows the protective medium to cool the heated area of ​​the battery cell 401, while also reducing the high-temperature gas ejected from the explosion-proof valve 4012 when the battery cell 401 experiences thermal runaway. This helps control the spread of heat and improves the safety of the battery pack.

[0066] In specific implementation, the battery cell 401 in this embodiment is preferably a blade-type battery cell 401. The battery module 400 of this embodiment is formed by stacking multiple blade-type battery cells 401 sequentially along the second direction, and adjacent blade-type battery cells 401 are welded together by a busbar 402. The busbar 402 is welded to the terminal post 4011 of the adjacent two battery cells 401. It should be noted that related structures of the battery cell 401 described in this embodiment that are not mentioned, such as the explosion-proof valve 4012, can be referred to the related structures of the blade-type battery cell 401 well known to those skilled in the art, and will not be described in detail here.

[0067] Furthermore, it is worth mentioning that the plurality of injection ports 3013 mentioned in the first aspect embodiment can be arranged corresponding to the plurality of busbars 402 of the battery module 400. Specifically, the injection ports 3013 can be arranged in a one-to-one correspondence with the busbars 402, or every two injection ports 3013 can correspond to one busbar 402. More preferably, the injection ports 3013 can be arranged directly above the busbars 402, so that the coolant sprayed from the injection ports 3013 can flow through the busbars 402 below under the action of gravity, thereby achieving a better cooling effect.

[0068] In this embodiment, during actual operation, when the battery pack is in a slow charging state, only the upper flow channel 3021 and the lower flow channel 2011 of the top plate 300 are operational, while the channel 3022 for the flow of the protective medium is inactive. During high-rate fast charging, the channel 3022 for the flow of the protective medium operates in conjunction with the coolant flowing in the upper flow channel 3021 and the lower flow channel 2011 to cool the battery.

[0069] Specifically, in this embodiment, when the battery pack requires additional cooling during high-rate fast charging, the immersion liquid enters the channel 3022 from the inlet 30223 and is then sprayed out from the nozzle 3013 onto the terminals 4011 and busbar 402 of the battery cell 401 for cooling. Under gravity, the immersion liquid flows downwards, entering the connecting cavity 203 through the through hole 2012 of the lower cooling plate 201, which is surrounded by the lower cooling plate 201, the bottom protective plate 202, and the sealing strip 204. Then, under the action of the first pumping unit 5021, it is collected from the connecting hole 2021 into the first storage tank 5011. The relevant control strategy controls the three-way valve 505 so that the second pumping unit 5031 can only draw immersion liquid from the first storage tank 5011. Under the action of the second pumping unit 5031, the immersion liquid reaches the nozzle 3013, ultimately forming a closed loop.

[0070] When the protective medium in this embodiment is in operation, i.e., when the battery is in thermal runaway, the control method is as follows: the relevant control strategy controls the three-way valve 505 so that the second pumping unit 5031 can only draw extinguishing agent from the second storage tank 5012. Under the action of the second pumping unit 5031, the extinguishing agent reaches the inlet 30223. The extinguishing agent enters the channel 3022 from the inlet 30223 and is then sprayed out from the spray port 3013. When the blade-type battery cell 401 experiences thermal runaway, the corresponding explosion-proof valve 4012 of the battery cell 401 will open, spraying out high-temperature gas. The extinguishing agent sprayed from the spray port 3013 can reduce the temperature of the sprayed gas, prevent heat spread, and at the same time consume the active functional groups in the high-temperature gas, reducing the possibility of high-temperature gas ignition, thereby significantly reducing the risk of thermal runaway.

[0071] The battery pack in this embodiment, by setting the battery pack structure as described above, can improve the heat dissipation capacity of the battery pack, and at the same time, it is also conducive to improving the control capability of the battery pack against thermal runaway, thereby improving the safety performance of the battery pack.

[0072] The above descriptions are merely some embodiments of this application and are not intended to limit this application. The technical features or structures in the foregoing different embodiments can be arbitrarily combined to form other specific technical solutions as needed. For those skilled in the art, this application can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of the claims of this application.

Claims

1. A battery pack housing structure, characterized in that: It includes a frame forming an installation cavity, a bottom plate assembly at the bottom of the frame, and a top plate at the top of the frame; The top plate has an upper flow channel for coolant to flow through and a channel for protective medium to flow through, and a spray nozzle communicating with the channel is provided at the bottom of the top plate. The spray nozzle is used to spray the protective medium. The base plate assembly is provided with a lower flow channel for coolant flow and a connecting cavity that connects the mounting cavity to an external storage device.

2. The battery pack housing structure according to claim 1, characterized in that: The channel includes a plurality of transverse channels spaced apart on the top plate along a first direction, and a longitudinal channel disposed between one end of the plurality of transverse channels. The longitudinal channel is provided with an inlet for the protective medium to enter, and each of the transverse channels is provided with a plurality of spray ports spaced apart.

3. The battery pack housing structure according to claim 2, characterized in that: Relative to the inlet, the liquid inlet and liquid outlet of the upper flow channel are located at the other end of the top plate.

4. The battery pack housing structure according to claim 2, characterized in that: The frame includes an annular frame body and a partition beam disposed within the frame body, the partition beam dividing the mounting cavity into a plurality of spaced-apart cavities; Each of the compartments can accommodate a battery module, and the top plate is provided with a transverse channel on each of the two opposite sides of each compartment.

5. The battery pack housing structure according to any one of claims 1 to 4, characterized in that: The bottom plate assembly includes a lower cooling plate and a bottom protective plate disposed at the bottom of the lower cooling plate. The lower flow channel is disposed on the lower cooling plate, and the connecting cavity is formed by the lower cooling plate and the bottom protective plate. The lower cold plate is provided with a through hole connecting the mounting cavity and the connecting cavity, and the bottom protective plate is provided with a connecting hole connecting the connecting cavity and the external storage device.

6. A battery pack, characterized in that: The battery pack housing structure according to any one of claims 1 to 5, the battery module disposed in the mounting cavity, and the storage device.

7. The battery pack according to claim 6, characterized in that: The storage device includes a storage tank storing the protective medium, an inlet pipe and an outlet pipe communicating with the storage tank, a first pumping unit provided on the inlet pipe and a second pumping unit provided on the outlet pipe; The inlet pipe is connected to the connecting cavity, and the outlet pipe is connected to the channel.

8. The battery pack according to claim 7, characterized in that: The inlet pipe and the outlet pipe are connected to the storage tank through the same connecting pipe; The connecting pipe is connected to the inlet pipe and the outlet pipe via a three-way valve.

9. The battery pack according to claim 6, characterized in that: The top of the battery module is connected to the top plate by a thermally conductive structural adhesive, and the injection nozzle and the thermally conductive structural adhesive are staggered in the thickness direction of the frame.

10. The battery pack according to any one of claims 6 to 9, characterized in that: The battery module includes a plurality of battery cells arranged sequentially along the second direction, and each battery cell has a terminal post and an explosion-proof valve at both ends along its length. Each of the battery cells has a preset space between its two ends along its length and the frame, and the preset space is used for the passage of the protective medium ejected from the injection port.

Images