An emergency treatment device and method for thermal runaway of electric vehicle battery pack

Abstract

This invention relates to the field of thermal runaway treatment technology for electric vehicle battery packs, and provides an emergency treatment device and method for thermal runaway in electric vehicle battery packs. The device includes multiple isolation mechanisms correspondingly arranged between two adjacent battery cells. Each isolation mechanism includes two isolation modules, each including a housing, a flame-retardant component disposed inside the housing, and a drive component disposed outside the housing. The flame-retardant component includes a storage container for storing flame retardant and multiple output pipes communicating with the storage container. The output pipes of the two isolation modules in the isolation mechanism are oriented in opposite directions, and the output pipes penetrate the housing and contact the battery cells, creating a gap between the housing and the battery cells. The drive component drives the storage container to spray flame retardant through the output pipes into the gap to form a flame-retardant isolation layer on the side of the battery cells. This invention can actively form a flame-retardant isolation layer between the battery cells by utilizing the cooperation of the drive component and the flame-retardant component, effectively preventing the spread of thermal runaway.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle battery pack thermal runaway treatment technology, specifically to an emergency treatment device and method for electric vehicle battery pack thermal runaway. Background Technology

[0002] With the rapid development of new energy vehicles, high-energy-density lithium-ion batteries are widely used in electric vehicles. However, lithium batteries are prone to thermal runaway when subjected to extreme conditions such as internal short circuits, external collisions, and heat accumulation, which can lead to combustion or even explosion, seriously endangering the lives of people and the safety of vehicles and property.

[0003] Currently, the industry has deployed various safety technologies to mitigate risks. For example, Tesla uses a highly integrated intelligent battery management system (BMS) to monitor temperature, voltage, and charge / discharge rates in real time, and limits current or cuts off power in case of abnormalities. BYD's "blade battery" structure adopts a high-strength steel shell design and sets fireproof and heat-insulating layers between cells to effectively delay heat diffusion time. In addition, companies such as CATL are also developing flame-retardant electrolytes and adding heat-stabilizing additives to improve the thermal safety of the materials themselves.

[0004] However, these measures are mostly passive protection or pre-accident prevention mechanisms, and they are still significantly insufficient in the rapid response after thermal runaway actually occurs. They cannot actively deal with the situation of cell thermal runaway in the early stage of an accident, which means that the battery pack is still very likely to catch fire due to cell thermal runaway. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides an emergency treatment device and method for thermal runaway of electric vehicle battery packs. It can passively prevent thermal runaway cells from rapidly transferring heat to other cells by forming an air insulation layer between the cells. It can also actively form a flame-retardant isolation layer between the cells by utilizing the cooperation of drive components and flame-retardant components, effectively preventing the spread of thermal runaway and ensuring the safety of electric vehicles and occupants.

[0006] To achieve the above objectives, the specific solution adopted by the present invention is as follows: an emergency handling device for thermal runaway of an electric vehicle battery pack, comprising multiple isolation mechanisms correspondingly disposed between two adjacent battery cells. Each isolation mechanism includes two isolation modules. Each isolation module includes a housing, a flame-retardant component disposed inside the housing, and a drive component disposed outside the housing. The flame-retardant component includes a storage container for storing flame retardant and multiple output pipes communicating with the storage container. The output pipes of the two isolation modules in the isolation mechanism are oriented in opposite directions, and the output pipes penetrate the housing and contact the battery cells to form a gap between the housing and the battery cells. The drive component is used to drive the storage container to spray flame retardant through the output pipes into the gap to form a flame-retardant isolation layer on the side of the battery cells.

[0007] As a further optimization of the above-mentioned emergency treatment device for thermal runaway of electric vehicle battery pack: the storage container includes a frame fixedly disposed inside the outer shell, the frame being fixedly connected to the first side wall of the outer shell, and a distance being left between the frame and the second side wall of the outer shell, the first side wall and the second side wall being disposed opposite to each other, a movable plate being slidably disposed in the frame, and a cavity for containing the flame retardant being formed between the movable plate and the first side wall of the outer shell, and the cavity being connected to the output pipe.

[0008] As a further optimization of the above-mentioned emergency treatment device for thermal runaway of electric vehicle battery pack: a soft connecting piece is fixedly connected to the side of the moving plate facing the cavity, and the edge of the soft connecting piece extends to the periphery of the moving plate and is fixedly connected to the inner sidewall of the frame.

[0009] As a further optimization of the above-mentioned emergency treatment device for thermal runaway of electric vehicle battery pack: at least one groove is provided on the moving plate, and both ends of the groove extend to the edge of the moving plate, a part of the groove is located outside the frame, and the soft connecting piece closes the opening of the groove.

[0010] As a further optimization of the above-mentioned emergency handling device for thermal runaway of electric vehicle battery pack: the middle part of the moving plate is bent outward from the cavity to form the groove.

[0011] As a further optimization of the above-mentioned emergency treatment device for thermal runaway of electric vehicle battery pack: the drive assembly includes a base plate fixedly mounted on the outer shell, a mounting groove is formed on the surface of the base plate, and a part of the mounting groove is connected to the outer shell through a vent hole formed on the outer shell. The mounting groove is provided with a raw material for generating gas and at least one trigger for triggering the raw material. After the raw material is triggered by the trigger to generate gas, the gas can enter the interior of the outer shell through the vent hole.

[0012] As a further optimization of the above-mentioned emergency treatment device for thermal runaway of electric vehicle battery pack: the raw material is sodium azide, the trigger is used to heat the raw material to decompose the raw material and generate nitrogen gas, and multiple triggers are configured and connected to a trigger control unit.

[0013] As a further optimization of the above-mentioned emergency handling device for thermal runaway of electric vehicle battery pack: the device includes an emergency handling control module and a status acquisition mechanism. The status acquisition mechanism includes multiple multi-modal acquisition modules correspondingly arranged on the side of the battery cell. The multi-modal acquisition modules are used to acquire the temperature parameters, electrical parameters and gas leakage parameters of the battery cell. The emergency handling control module is electrically connected to all multi-modal acquisition modules and all the trigger control units.

[0014] As a further optimization of the above-mentioned emergency handling device for thermal runaway of electric vehicle battery pack: the multiple output tubes in the isolation module are arranged in an array, and a distance is left between two adjacent output tubes to form an installation space for installing the multimodal acquisition module.

[0015] An emergency treatment method for thermal runaway of an electric vehicle battery pack, based on the aforementioned emergency treatment device for thermal runaway of an electric vehicle battery pack, includes the following steps:

[0016] Real-time monitoring of the cell's operating status, and determination of whether the cell has experienced thermal runaway based on the cell's operating status;

[0017] When a battery cell experiences thermal runaway, the drive component in the isolation module corresponding to the battery cell is activated.

[0018] The storage container is driven by a drive component to spray the flame retardant through the output pipe into the gap between the isolation module and the battery cell, thereby forming the flame retardant isolation layer on the side of the battery cell.

[0019] Beneficial effects: This invention utilizes an isolation module to create a gap between two adjacent battery cells, forming an air insulation layer with the air in the gap. This slows down the heat transfer rate between the cells, preventing rapid heat transfer to other cells when one cell experiences thermal runaway. Furthermore, by incorporating a drive assembly and a flame-retardant assembly, this invention actively injects flame retardant into the gap, forming a flame-retardant isolation layer between adjacent cells. This further prevents thermal runaway cells from causing other cells to also experience thermal runaway, thus preventing the entire battery pack from burning and ensuring the safety of the electric vehicle and its occupants. Attached Figure Description

[0020] Figure 1 This is a structural diagram of the isolation mechanism;

[0021] Figure 2 This is a cross-sectional view of the isolation module;

[0022] Figure 3 yes Figure 2 A magnified view of part A in the middle;

[0023] Figure 4 This is a structural diagram of the frame and the movable plate;

[0024] Figure 5 This is a schematic diagram of the driver component;

[0025] Figure 6 This is a schematic diagram showing how the air vent is opened;

[0026] Figure 7 This is a schematic diagram illustrating the interaction between the isolation mechanism and the battery cell.

[0027] Figure descriptions: 1-Outer shell, 2-Drive assembly, 3-Output tube, 4-Frame, 5-Moving plate, 6-Flame retardant, 7-Diaphragm, 8-Flexible connecting piece, 9-Groove, 10-Base plate, 11-Mounting slot, 12-Trigger control unit, 13-Trigger, 14-Separator, 15-Raw material, 16-Gas vent, 17-Battery cell, 18-Gap. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] like Figures 1 to 3 as well as Figure 7 As shown, an emergency handling device for thermal runaway of an electric vehicle battery pack includes multiple isolation mechanisms correspondingly disposed between two adjacent battery cells 17. Each isolation mechanism includes two isolation modules. Each isolation module includes a housing 1, a flame-retardant component disposed inside the housing 1, and a drive component 2 disposed outside the housing 1. The flame-retardant component includes a storage container for storing flame retardant 6 and multiple output pipes 3 communicating with the storage container. The output pipes 3 of the two isolation modules in the isolation mechanism are oriented in opposite directions, and the output pipes 3 penetrate the housing 1 and contact the battery cell 17 to form a gap 18 between the housing 1 and the battery cell 17. The drive component 2 is used to drive the storage container to spray the flame retardant 6 through the output pipes 3 into the gap 18 to form a flame-retardant isolation layer on the side of the battery cell 17.

[0030] When this invention is applied to an electric vehicle battery pack, the isolation mechanism is correspondingly set between two adjacent cells 17 in the electric vehicle battery pack. The output tubes 3 of the two isolation modules in the isolation mechanism are in contact with the two adjacent cells 17 one by one. Since the output tubes 3 extend out of the outer shell 1, the output tubes 3 can form a gap 18 between the outer shell 1 and the cell 17. The air in the gap 18 can form an air insulation layer between the two adjacent cells 17, which can slow down the heat transfer rate between the cells 17. When a cell 17 thermally runs away, the heat emitted by the faulty cell 17 can be prevented from being quickly transferred to other adjacent cells 17, thus protecting other normal cells 17. Based on this, when thermal runaway of cell 17 is confirmed, the corresponding isolation module is controlled to operate. Specifically, the drive component 2 in the isolation module is controlled to operate, and the flame retardant 6 in the storage container is driven to be sprayed and released into the gap 18 through the output pipe 3, thereby forming a flame retardant isolation layer between the isolation module and cell 17, that is, forming a flame retardant isolation layer on the side of cell 17, thereby isolating the faulty cell 17 from other normal cells 17. Even if the faulty cell 17 thermally runs away and catches fire, it will not cause other normal cells 17 to catch fire simultaneously.

[0031] This invention utilizes an isolation module to form a gap 18 between two adjacent battery cells 17. The air in the gap 18 forms an air insulation layer, which slows down the heat transfer rate between the battery cells 17. When a battery cell 17 experiences thermal runaway, it can prevent heat from being rapidly transferred to other battery cells 17. By setting up a drive component 2 and a flame-retardant component, this invention can actively spray flame retardant 6 into the gap 18, thereby forming a flame-retardant isolation layer between two adjacent battery cells 17. This further prevents the thermal runaway of a battery cell 17 from causing other battery cells 17 to also experience thermal runaway, thereby preventing the entire battery pack from burning and ensuring the safety of the electric vehicle and its occupants.

[0032] The specific structure of the storage container is as follows: The storage container includes a frame 4 fixedly installed inside the outer shell 1. The frame 4 is fixedly connected to the first side wall of the outer shell 1, and a distance is left between the frame 4 and the second side wall of the outer shell 1. The first side wall and the second side wall are arranged opposite to each other. A movable plate 5 is slidably installed in the frame 4. A cavity for containing flame retardant 6 is formed between the movable plate 5 and the first side wall of the outer shell 1, and the cavity is connected to the output pipe 3. Under normal conditions, the flame retardant 6 is contained in the cavity. When the battery cell 17 experiences thermal runaway, the drive assembly 2 is activated. The drive assembly 2 drives the movable plate 5 to slide towards the output pipe 3, thereby squeezing the flame retardant 6 in the cavity, so that the flame retardant 6 can be sprayed into the gap 18 between the battery cells 17 through the output pipe 3, thereby successfully forming a flame-retardant isolation layer. The storage container has a simple structure. The drive component 2 only needs to drive the moving plate 5 to push the flame retardant 6 out of the output tube 3. It is simple and quick and can quickly form multiple flame-retardant isolation layers around the thermally runaway cell 17, so as to avoid causing thermal runaway of other cells 17.

[0033] To ensure a tight seal between the movable plate 5 and the frame 4, and to prevent the flame retardant 6 from leaking into the outer shell 1, which could hinder its smooth ejection from the output pipe 3 and lead to uneven distribution or even gaps in the flame-retardant isolation layer, a flexible connecting piece 8 is fixedly connected to the side of the movable plate 5 facing the cavity. The edge of the flexible connecting piece 8 extends to the periphery of the movable plate 5 and is fixedly connected to the inner wall of the frame 4. The flexible connecting piece 8 significantly improves the sealing performance between the movable plate 5 and the frame 4, thus confining the flame retardant 6 within the cavity and preventing it from leaking into the outer shell 1. Furthermore, the flexible connecting piece 8 can deform during the movement of the movable plate 5, preventing obstruction of its movement and ensuring that the movable plate 5 can smoothly eject the flame retardant 6 from the output pipe 3.

[0034] Similarly, to prevent the flame retardant 6 from leaking from the output pipe 3, a diaphragm 7 is provided on the inner wall of the end of the output pipe 3 facing away from the outer casing 1. Under normal conditions, the diaphragm 7 can seal the output pipe 3, thereby preventing the flame retardant 6 from leaking. When the drive assembly 2 drives the moving plate 5 to move, the flame retardant 6 can squeeze the diaphragm 7 to rupture it, thereby ensuring that the flame retardant 6 can be smoothly sprayed from the output pipe 3 into the gap 18 to form a flame-retardant isolation layer.

[0035] like Figure 5 and Figure 6As shown, the specific structure of the drive assembly 2 is as follows: The drive assembly 2 includes a base plate 10 fixedly mounted on the housing 1. A mounting groove 11 is formed on the surface of the base plate 10, and a part of the mounting groove 11 is connected to the housing 1 through a vent hole 16 formed on the housing 1. A raw material 15 for generating gas and at least one trigger 13 for triggering the raw material 15 are provided in the mounting groove 11. After the raw material 15 is triggered by the trigger 13 to generate gas, the gas can enter the interior of the housing 1 through the vent hole 16. When thermal runaway of the battery cell 17 is detected, the trigger 13 is controlled to activate, and the raw material 15 is triggered by the trigger 13, causing the properties of the raw material 15 to change and generate gas. After the gas enters the housing 1 through the vent hole 16, it can push the moving plate 5 to move, thereby using the moving plate 5 to spray the flame retardant 6 from the output pipe 3 into the gap 18 to form a flame retardant isolation layer. The drive assembly 2 moves the moving plate 5 by releasing gas. It does not require a complex transmission structure. Only a vent hole 16 needs to be opened on the outer shell 1. The structure is simpler and easier to control. It can also reduce the size of the isolation module and avoid the isolation module occupying too much space, which would greatly reduce the number of cells 17 that the battery pack can contain, thus ensuring that the capacity of the battery pack can meet the needs of electric vehicles.

[0036] Furthermore, the raw material 15 is sodium azide, and the trigger 13 is used to heat the raw material 15 to decompose it and generate nitrogen gas. Multiple triggers 13 are configured and connected to a trigger control unit 12. Sodium azide is a white crystalline solid that rapidly decomposes into nitrogen gas when exposed to high temperatures. The nitrogen gas enters the outer shell 1 and pushes the moving plate 5, thereby injecting the flame retardant 6 from the cavity into the gap 18 through the output pipe 3 to form a flame-retardant isolation layer. On the other hand, the explosion of sodium azide generates a large amount of nitrogen gas, which then pushes the moving plate 5, causing the drive assembly 2 to move faster and inject the flame retardant 6 into the gap 18 through the output pipe 3 in a very short time. Sodium azide is widely used in automotive airbags; its specific triggering method, triggering principle, and reaction products are all conventional technologies in the field and will not be elaborated upon here.

[0037] Furthermore, a partition 14 is fixedly installed in the mounting slot 11, and the trigger 13 is fixed on the partition 14 to reinforce the trigger 13.

[0038] like Figure 4As shown, to further ensure that the gas released by the drive assembly 2 can smoothly drive the moving plate 5 after entering the housing 1, at least one groove 9 is provided on the moving plate 5, and both ends of the groove 9 extend to the edge of the moving plate 5. A part of the groove 9 is located outside the frame 4, and the flexible connecting piece 8 closes the opening of the groove 9. Some gas can enter the groove 9 and act on the flexible connecting piece 8, accelerating the deformation of the flexible connecting piece 8, thereby ensuring that the moving plate 5 can move smoothly.

[0039] The groove 9 is specifically designed as follows: the middle part of the moving plate 5 is bent outwards from the cavity to form the groove 9. Forming the groove 9 by bending eliminates welding steps, making it easier to process. Furthermore, the groove 9 extends along a direction perpendicular to the electric vehicle chassis, and both ends of the groove 9 contact the inner wall of the frame 4, increasing the contact area between the moving plate 5 and the upper and lower edges of the frame 4. This prevents the moving plate 5 from tilting within the frame 4, ensuring that the moving plate 5 can move smoothly towards the output pipe 3 when propelled by gas. Similarly, two grooves 9 can be placed at the edges of the moving plate 5, contacting the other two edges of the frame 4, thus preventing the moving plate 5 from tilting in any direction.

[0040] To enable rapid control of the drive assembly 2 to release the flame retardant 6 in the event of thermal runaway of cell 17, the device includes an emergency handling control module and a status acquisition mechanism. The status acquisition mechanism includes multiple multimodal acquisition modules correspondingly positioned on the side of cell 17. These modules collect temperature, electrical, and gas leakage parameters of cell 17. The emergency handling control module is electrically connected to all multimodal acquisition modules and all trigger control units 12. The multimodal acquisition modules can be implemented using existing sensor components in the battery pack, including temperature sensors, current and voltage sensors, and gas sensors, all of which are mature existing technologies and will not be elaborated further. The emergency handling control module can use an ARM series processor, which is also a mature existing technology and will not be elaborated further.

[0041] To ensure that the flame retardant 6 can form a uniform flame retardant isolation layer around the battery cell 17, multiple output tubes 3 in the isolation module are arranged in an array, and a distance is left between two adjacent output tubes 3 to form an installation space for installing the multimodal acquisition module.

[0042] The present invention further provides an emergency treatment method for thermal runaway of an electric vehicle battery pack, based on the above-mentioned emergency treatment device for thermal runaway of an electric vehicle battery pack, the method comprising S1 to S3.

[0043] S1. Monitor the operating status of cell 17 in real time, and determine whether cell 17 has thermal runaway based on the operating status of cell 17.

[0044] S2. When cell 17 experiences thermal runaway, the drive component 2 in the isolation module corresponding to cell 17 is activated.

[0045] S3. Using the drive component 2, the storage container is driven to spray the flame retardant 6 through the output pipe 3 into the gap 18 between the isolation module and the battery cell 17, and the flame retardant 6 forms a flame retardant isolation layer on the side of the battery cell 17.

[0046] Finally, it should be noted that flame retardant 6 is a very mature existing technology in this field, and the appropriate material and model can be selected according to actual needs, which will not be elaborated here.

[0047] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An emergency handling device for thermal runaway of an electric vehicle battery pack, characterized in that, The device includes multiple isolation mechanisms correspondingly disposed between two adjacent battery cells (17). Each isolation mechanism includes two isolation modules. Each isolation module includes a housing (1), a flame-retardant component disposed inside the housing (1), and a drive component (2) disposed outside the housing (1). The flame-retardant component includes a storage container for storing flame retardant (6) and multiple output pipes (3) connected to the storage container. The output pipes (3) of the two isolation modules in the isolation mechanism are in opposite directions, and the output pipes (3) penetrate the housing (1) and contact the battery cell (17) to form a gap (18) between the housing (1) and the battery cell (17). The drive component (2) is used to drive the storage container to spray the flame retardant (6) into the gap (18) through the output pipes (3) to form a flame-retardant isolation layer on the side of the battery cell (17). The storage container includes a frame (4) fixedly disposed inside the outer shell (1), the frame (4) being fixedly connected to the first side wall of the outer shell (1), and a distance being left between the frame (4) and the second side wall of the outer shell (1). The first side wall and the second side wall are disposed opposite to each other. A movable plate (5) is slidably disposed in the frame (4), and a cavity for accommodating the flame retardant (6) is formed between the movable plate (5) and the first side wall of the outer shell (1), and the cavity is connected to the output pipe (3). The drive assembly (2) includes a base plate (10) fixedly mounted on the outer shell (1). A mounting groove (11) is provided on the surface of the base plate (10), and a part of the mounting groove (11) is connected to the outer shell (1) through a gas guide hole (16) on the outer shell (1). The mounting groove (11) is provided with a raw material (15) for generating gas and at least one trigger (13) for triggering the raw material (15). After the raw material (15) is triggered by the trigger (13) to generate gas, the gas can enter the interior of the outer shell (1) through the gas guide hole (16).

2. The emergency handling device for thermal runaway of an electric vehicle battery pack as described in claim 1, characterized in that, The movable plate (5) is fixedly connected to a soft connecting piece (8) on the side facing the cavity. The edge of the soft connecting piece (8) extends to the periphery of the movable plate (5) and is fixedly connected to the inner wall of the frame (4).

3. The emergency handling device for thermal runaway of an electric vehicle battery pack as described in claim 2, characterized in that, The movable plate (5) is provided with at least one groove (9), and the two ends of the groove (9) extend to the edge of the movable plate (5). A part of the groove (9) is located outside the frame (4), and the soft connecting piece (8) closes the opening of the groove (9).

4. The emergency handling device for thermal runaway of an electric vehicle battery pack as described in claim 3, characterized in that, The middle part of the movable plate (5) is bent outwards from the cavity to form the groove (9).

5. The emergency handling device for thermal runaway of an electric vehicle battery pack as described in claim 1, characterized in that, The raw material (15) is sodium azide, and the trigger (13) is used to heat the raw material (15) to decompose the raw material (15) and generate nitrogen gas. The trigger (13) is configured as multiple and is connected to a trigger control unit (12).

6. The emergency handling device for thermal runaway of an electric vehicle battery pack as described in claim 1, characterized in that, The device includes an emergency handling control module and a status acquisition mechanism. The status acquisition mechanism includes multiple multimodal acquisition modules correspondingly arranged on the side of the battery cell (17). The multimodal acquisition modules are used to acquire the temperature parameters, electrical parameters and gas leakage parameters of the battery cell (17). The emergency handling control module is electrically connected to all multimodal acquisition modules and all the trigger control units (12).

7. An emergency handling device for thermal runaway of an electric vehicle battery pack as described in claim 6, characterized in that, The multiple output tubes (3) in the isolation module are arranged in an array, and a distance is left between two adjacent output tubes (3) to form an installation space for installing the multimodal acquisition module.

8. An emergency handling method for thermal runaway of an electric vehicle battery pack, characterized in that, Based on the emergency treatment device for thermal runaway of an electric vehicle battery pack as described in any one of claims 1-7, the method includes the following steps: The operating status of the battery cell (17) is monitored in real time, and the battery cell (17) is judged to have thermal runaway based on the operating status of the battery cell (17); When the battery cell (17) experiences thermal runaway, the drive component (2) in the isolation module corresponding to the battery cell (17) is activated; The storage container is driven by the drive assembly (2) to spray the flame retardant (6) through the output tube (3) into the gap (18) between the isolation module and the battery cell (17), and the flame retardant (6) forms the flame retardant isolation layer on the side of the battery cell (17).

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