Battery module and thermal runaway control system thereof

Abstract

The application belongs to the technical field of batteries, and discloses a battery module and a thermal runaway control system thereof. The battery module comprises a plurality of battery cells arranged in an array, each of the battery cells is provided with a top cover, and a liquid injection hole in communication with the inside of the battery cell is formed in the top cover. An exhaust branch pipe is in communication with the liquid injection hole, and a control valve is arranged in each of the exhaust branch pipes. The control valve is used for controlling the conduction and closing of the exhaust branch pipe. The battery module can realize independent control of the exhaust branch pipes of the battery cells, and can discharge and treat the high-temperature gas generated by the battery cell with thermal runaway in advance before the thermal runaway of the battery module occurs, thereby delaying or even inhibiting the occurrence of thermal runaway and improving the safety of the battery module. Furthermore, the liquid injection hole is used as an exhaust passage, the number of openings of the battery module is reduced, and the manufacturing cost of the battery module is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of battery technology, specifically relating to a battery module and its thermal runaway control system. Background Technology

[0002] A battery module is formed by arranging multiple cells. When the battery module is working, various unforeseen operating conditions or quality defects may cause thermal runaway of the cells inside the battery module. The cells that have thermal runaway will generate high-temperature gas and eject the contents of the cells. Since the battery module is in a closed state, the high-temperature gas will spread in the internal space of the battery module and cannot dissipate in time, which may cause other cells to also experience thermal runaway, thus leading to the risk of the entire battery module exploding or catching fire. Utility Model Content

[0003] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a battery module and its thermal runaway control system.

[0004] In a first aspect, this utility model provides a battery module, the battery module comprising a plurality of battery cells arranged in an array, each battery cell having a top cover, and the top cover having an injection hole communicating with the interior of the battery cell;

[0005] The injection hole is connected to an exhaust branch pipe, and each exhaust branch pipe is equipped with a control valve, which is used to control the opening and closing of the exhaust branch pipe.

[0006] The battery module provided by this utility model has venting branches connected to the electrolyte injection holes of the battery cells, and each venting branch is equipped with a control valve, enabling independent control of the venting branches of each battery cell. This allows for the pre-emptive removal of high-temperature gases generated by thermal runaway cells before they experience thermal runaway, delaying or even suppressing the occurrence of thermal runaway, improving the safety of the battery module, and preventing the spread of high-temperature gases within the battery module's internal space, thus avoiding impact on adjacent cells. Furthermore, directly utilizing the electrolyte injection holes as venting channels reduces the number of openings in the battery module, lowering its complexity and manufacturing cost.

[0007] In addition, the battery module of this utility model may also have the following additional technical features:

[0008] In some embodiments, the battery module further includes a manifold, wherein the end of each exhaust branch pipe away from the injection hole is connected to the manifold.

[0009] In some embodiments, the battery module further includes an exhaust manifold, and the manifold is connected to the exhaust manifold.

[0010] In some embodiments, the multiple battery cells arranged in an array are provided with end plates on both sides. The end plates are provided with interconnected mounting ports and mounting slots. The mounting ports are used to install the manifold, and the mounting slots are used to install the exhaust manifold.

[0011] In some embodiments, at least one of the exhaust branch pipe, the manifold, and the exhaust main pipe is a metal pipe.

[0012] In some embodiments, the vent branch pipe is connected to the injection hole via an vent connector, and the vent connector is fixedly or detachably connected to the top cover at the injection hole.

[0013] In some embodiments, the injection holes on the top covers of adjacent cells are staggered.

[0014] In some embodiments, a heat insulation element is provided between adjacent battery cells.

[0015] A second aspect of this utility model provides a battery module thermal runaway control system. The system includes the battery module and the gas extraction device described in any embodiment of this application. The gas extraction device is connected to the exhaust branch pipe. The gas extraction device is used to discharge the gas generated by the thermal runaway of the battery cell through the corresponding exhaust branch pipe when the battery cell experiences thermal runaway.

[0016] In some embodiments, the system further includes a controller, and a detection device is disposed on the battery cell. The signal output terminal of the detection device is electrically connected to the signal input terminal of the controller, and the signal output terminal of the controller is electrically connected to the signal input terminal of the control valve. The detection device includes at least one of a temperature sensor, a voltage sensor, and a pressure sensor.

[0017] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0019] Figure 1 This is a three-dimensional structural diagram of the battery module provided in the embodiments of this application;

[0020] Figure 2 This is a three-dimensional structural diagram of the battery module provided in the embodiments of this application;

[0021] Figure 3 This is a schematic diagram of the cell structure provided in an embodiment of this application;

[0022] Figure 4 This is a schematic diagram of the manifold structure provided in an embodiment of this application;

[0023] Figure 5 This is a schematic diagram of the end plate structure provided in an embodiment of this application;

[0024] Figure 6 This is a schematic diagram of the exhaust connector structure provided in an embodiment of this application.

[0025] In the above image:

[0026] 100 Battery module; 110 Battery cell; 111 Top cover; 112 Liquid filling hole;

[0027] 120 Exhaust connector; 121 Exhaust branch pipe; 122 Manifold; 123 Main exhaust pipe;

[0028] 130 End plate; 131 Mounting port; 132 Mounting slot;

[0029] 140 Thermal insulation; 150 Insulation; 160 Output pole mounting base; 170 Straps. Detailed Implementation

[0030] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the relevant utility model and not intended to limit the scope of the utility model. Furthermore, it should be noted that, for ease of description, only the parts relevant to the utility model are shown in the accompanying drawings.

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0032] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” as used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0033] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open and encompassing, that is, "including, but not limited to".

[0034] In the description of this specification, the terms "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples," etc., are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0035] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0036] The application of power battery modules 100, such as lithium-ion batteries, is becoming increasingly common, and with continuously rising customer demands, energy density is becoming higher and higher. The higher the energy density of lithium-ion batteries, the higher their instability, and thermal runaway cannot be completely prevented during use. Analysis of the sources of thermal runaway in cell 110 reveals that a series of reactions occur before thermal runaway occurs, releasing gases of different compositions. The interaction of these gases exacerbates side reactions. Furthermore, because the battery module 100 is in a closed state, adjacent cells 110 also face the risk of thermal runaway, thus posing a risk of explosion and fire to the battery module 100.

[0037] The first aspect of this utility model, with reference to... Figures 1 to 3 A battery module 100 is provided, the battery module 100 includes a plurality of battery cells 110 arranged in a row, each battery cell 110 is provided with a top cover 111, and the top cover 111 is provided with a liquid injection hole 112 communicating with the inside of the battery cell 110.

[0038] The injection hole 112 is connected to an exhaust branch pipe 121, and each exhaust branch pipe 121 is provided with a control valve, which is used to control the opening and closing of the exhaust branch pipe 121.

[0039] Specifically, the battery module 100 is formed by stacking multiple battery cells 110. Each battery cell 110 has a top cover 111 on top, and the top cover 111 has an injection hole 112. The injection hole 112 is connected to the inside of the battery cell 110, and electrolyte is injected into the battery cell 110 through the injection hole 112. The injection hole 112 of each battery cell 110 is connected to an exhaust branch pipe 121, and each exhaust branch pipe 121 of each battery cell 110 is equipped with a control valve, which can be a solenoid valve, a mechanical valve (such as a spring pressure valve), etc. When the battery module 100 is in normal working condition, the control valve controls the exhaust branch pipe 121 to close, ensuring the sealing of the battery module 100. When a cell 110 of the battery module 100 experiences thermal runaway, the control valve corresponding to the thermal runaway cell 110 controls the exhaust branch pipe 121 to open, and the high-temperature gas generated by the thermal runaway cell 110 is discharged from the exhaust branch pipe 121. This prevents the high-temperature gas from accumulating inside the battery module 100, thus solving the technical problem of high-temperature gas accumulating inside the battery module 100 when it experiences thermal runaway.

[0040] The battery module 100 provided by this utility model can achieve independent control of the exhaust pipes 121 of each cell 110. Before thermal runaway occurs in a cell 110 of the battery module 100, the high-temperature gas generated by the thermally runaway cell 110 is discharged in advance, delaying or even inhibiting the occurrence of thermal runaway, improving the safety of the battery module 100, and preventing the spread of high-temperature gas within the battery module 100, thus avoiding its impact on adjacent cells 110. Furthermore, by directly utilizing the liquid injection hole 112 as an exhaust channel, the number of openings in the battery module 100 is reduced, lowering the complexity and manufacturing cost of the battery module 100.

[0041] In some implementations, reference Figure 1 , Figure 2 and Figure 4 The battery module 100 also includes a manifold 122, and one end of each exhaust branch pipe 121 away from the liquid injection hole 112 is connected to the manifold 122.

[0042] In this example, multiple exhaust branches 121 are converged into a unified manifold 122, which avoids the complex layout caused by decentralized exhaust and can improve the overall exhaust efficiency, safety and integration of the battery module 100.

[0043] In some implementations, reference Figure 1 and Figure 2 The battery module 100 also includes an exhaust manifold 123, and the manifold 122 is connected to the exhaust manifold 123.

[0044] Specifically, the exhaust manifold 123 can discharge the high-temperature gas generated by the thermal runaway cell 110 to the outside of the battery module 100, avoiding the risk of explosion and fire caused by the accumulation of high-temperature gas inside the battery module 100, and improving the safety of the battery module 100.

[0045] In some implementations, reference Figure 1 , Figure 2 and Figure 5 The multiple battery cells 110 arranged in an array are provided with end plates 130 on both sides. The end plates 130 are provided with a connected mounting port 131 and a mounting groove 132. The mounting port 131 is used to install the manifold 122, and the mounting groove 132 is used to install the exhaust manifold 123.

[0046] Specifically, arranging the individual battery cells 110 between the two end plates 130 ensures accurate alignment and secure positioning of each cell 110. One end plate 130 has a connected mounting port 131 and mounting groove 132. The mounting port 131 can be located at the center of the top of the end plate 130, and the mounting groove 132 can be located at the top edge of the end plate 130. The mounting port 131 is used to install the busbar 122, and the mounting groove 132 is used to install the exhaust manifold 123. In this example, using the mounting port 131 and mounting groove 132 on the end plate 130 to install the busbar 122 and exhaust manifold 123 improves the integration of the battery module 100 and saves space. Furthermore, securing the busbar 122 and exhaust manifold 123 with the end plate 130 prevents them from loosening due to vibration.

[0047] Understandably, reference Figure 1 and Figure 2 The multiple battery cells 110 arranged in a row have output electrode mounting slots 132 on their two end plates 130. The output electrode mounting slots 132 are used to install output electrode mounting seats 160, which serve as the positive and negative output interfaces of the battery module 100, connecting the internal battery cells 110 of the battery module 100 to external systems, ensuring normal current transmission. The end plates 130 also have multiple weight-reduction slots, which can reduce the overall weight of the display module, reduce material usage, and lower costs.

[0048] In some embodiments, at least one of the exhaust branch pipe 121, the manifold 122, and the exhaust main pipe 123 is a metal pipe.

[0049] Specifically, the metal tube can withstand the high-temperature gases during thermal runaway of the battery cell 110, preventing melting or deformation. Furthermore, the metal tube has good heat dissipation performance, effectively dissipating the heat generated by the high-temperature gases. Preferably, the metal tube can be a corrugated pipe to further increase the heat dissipation area and improve the safety of the battery module 100.

[0050] In some implementations, reference Figure 1 , Figure 2 and Figure 6 The exhaust branch pipe 121 is connected to the injection hole 112 via an exhaust connector 120. The exhaust connector 120 is fixedly or detachably connected to the top cover 111 at the injection hole 112.

[0051] Specifically, the exhaust connector 120 and the top cover 111 are fixedly connected by welding, riveting or other methods, which ensures a firm connection and prevents the exhaust connector 120 from falling off due to exhaust vibration of the exhaust branch pipe 121; or, the exhaust connector 120 and the top cover 111 are connected by threads or other detachable methods, which facilitates the disassembly, cleaning and replacement of the exhaust connector 120 and the exhaust branch pipe 121.

[0052] In some implementations, reference Figure 1 and Figure 2 The liquid injection holes 112 on the top cover 111 of adjacent cells 110 are staggered.

[0053] Specifically, the injection holes 112 of adjacent cells 110 are staggered to facilitate the arrangement of the exhaust branches 121 above the cells 110 and avoid mutual interference between the exhaust branches 121.

[0054] In some implementations, reference Figure 1 and Figure 2 A heat insulation element 140 is provided between adjacent battery cells 110.

[0055] Specifically, thermal insulation components 140, such as foam or aerogel, can be installed between adjacent battery cells 110. When a battery cell 110 experiences thermal runaway due to abnormal conditions such as overcharging, over-discharging, or short circuit, it will rapidly heat up and release a large amount of heat. The thermal insulation component 140 can effectively block the conduction of heat to adjacent battery cells 110 and provide additional buffering and protection to prevent damage caused by mutual friction between battery cells 110 during transportation or use.

[0056] It should be noted that the reference Figure 1 and Figure 2 An insulating component 150 can be installed between the end plate 130 and the adjacent battery cell 110. The insulating component 150 can be an insulating film, insulating gasket, plastic bracket or insulating board, etc., to avoid the end plate 130 (metal material) from directly contacting the battery cell 110 and causing short circuit or leakage current problems.

[0057] refer to Figure 1 and Figure 2Each battery cell 110 and the outer surface of the end plate 130 are bound with straps 170 (steel straps, fiber-reinforced plastic straps, etc.) to tightly bind multiple battery cells 110 together, preventing displacement of the battery cells 110 during vibration, impact, or flipping, avoiding loosening of the battery cell 110 terminal connections, and maintaining the stability and integrity of the battery module 100. The busbar 122 is provided with clearance holes to allow the straps 170 to pass through, ensuring the binding force of the straps 170 on each battery cell 110. The battery cell 110 provided in this embodiment can be a prismatic lithium-ion battery, etc.

[0058] In a second aspect, this utility model provides a battery module thermal runaway control system. The system includes a battery module 100 as described in any embodiment of this application and a vacuum device. The vacuum device is connected to the exhaust branch pipe 121. The vacuum device is used to discharge the gas generated by the thermal runaway of the battery cell 110 through the corresponding exhaust branch pipe 121 when the battery cell 110 experiences thermal runaway.

[0059] Specifically, the evacuation equipment includes a vacuum pump, which is connected to the exhaust branch pipe 121. The negative pressure provided by the vacuum pump can quickly expel the high-temperature gas generated by the thermal runaway cell 110, further improving the safety of the battery module 100.

[0060] It should be noted that the vacuum pump is connected to each exhaust branch pipe 121 in sequence through the exhaust main pipe 123 and the manifold pipe 122. The same vacuum pump can realize the independent control of each exhaust branch pipe 121, saving costs. Moreover, the same vacuum pump can realize the simultaneous exhaust treatment of multiple exhaust branch pipes 121, improving the exhaust efficiency of the battery module 100.

[0061] In some embodiments, the system further includes a controller, and a detection device is disposed on the battery cell 110. The signal output terminal of the detection device is electrically connected to the signal input terminal of the controller, and the signal output terminal of the controller is electrically connected to the signal input terminal of the control valve. The detection device includes at least one of a temperature sensor, a voltage sensor, and a pressure sensor.

[0062] Specifically, the detection equipment can monitor the status of each battery cell 110 in real time, and the controller controls the status of the corresponding control valve of the battery cell 110 based on the status information of each battery cell 110 detected by the detection equipment. For example, a temperature sensor can detect the temperature information of the battery cell 110 in real time, a voltage sensor can detect the voltage information of the battery cell 110 in real time, and a pressure sensor can monitor the pressure information of the battery cell 110 in real time. Based on the detected temperature, voltage, and pressure information, the operating status (including normal operation and abnormal operation) of the corresponding battery cell 110 is identified. When the battery cell 110 is operating normally, the control valve controls the exhaust branch pipe 121 corresponding to the battery cell 110 to close; when the battery cell 110 is operating abnormally, the control valve controls the exhaust branch pipe 121 corresponding to the battery cell 110 to open, executing an exhaust strategy. In this example, through the coordinated operation of the detection equipment, controller, and control valve, abnormal battery cells 110 can be automatically identified, and thermal runaway of abnormal battery cells 110 can be automatically delayed and suppressed.

[0063] For example, if the temperature sensor of the detection device detects that the temperature of the battery cell 110 exceeds a preset temperature threshold (e.g., 60°C), and the temperature rise rate is not less than the temperature rise rate threshold (e.g., 1°C / s), and the duration is greater than a preset duration (e.g., 3s), then the controller determines that the battery cell 110 is malfunctioning, and the control valve controls the exhaust branch pipe 121 corresponding to the malfunctioning battery cell 110 to be open. Similarly, if the voltage sensor of the detection device detects that the voltage drop of the battery cell 110 exceeds a preset threshold (e.g., 25%) of the initial voltage (e.g., factory voltage) of the battery cell 110, and the temperature rise rate is not less than the temperature rise rate threshold (e.g., 1°C / s), then the controller determines that the battery cell 110 is malfunctioning, and the control valve controls the exhaust branch pipe 121 corresponding to the malfunctioning battery cell 110 to be open. Furthermore, if the pressure sensor of the detection device detects that the pressure of the battery cell 110 exceeds a preset pressure threshold, then the controller determines that the battery cell 110 is malfunctioning. The preset temperature threshold, temperature rise rate threshold, preset duration, and preset pressure threshold can be designed to other values ​​according to actual needs, and this application does not impose any special limitations.

[0064] It should be noted that, after the battery module 100 provided in this application embodiment determines that a certain cell 110 is malfunctioning, it can implement a venting strategy for the cells 110 adjacent to the malfunctioning cell 110. For example, the battery module 100 includes cells A, B, and C arranged in sequence. If the detection device determines that cell B is malfunctioning, the controller controls the exhaust branch pipe 121 corresponding to cell B to be open through the control valve, so that the high-temperature gas generated by cell B is discharged through the corresponding exhaust branch pipe 121, thereby suppressing the occurrence of side reactions inside the malfunctioning cell 110 and reducing the temperature of cell 110 to a certain extent. At the same time, the controller controls the control valves corresponding to cell A and cell C to be activated so that the exhaust branch pipes 121 corresponding to cell A and cell C are open, preventing the thermally abnormal cell 110 from spreading to adjacent cells 110.

[0065] Specifically, if the temperature sensor of the detection device detects that the temperature of cell B exceeds a preset temperature threshold (e.g., 200℃), an venting strategy is executed for cell B, and simultaneously for cells A and C. In this example, an venting strategy can be executed in advance for cells 110 adjacent to the abnormal cell 110, avoiding the thermal impact of the abnormal cell 110 on adjacent cells 110, and further improving the safety of the display module.

[0066] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the utility model involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A battery module (100), characterized in that, The battery module (100) includes a plurality of battery cells (110) arranged in a row. Each battery cell (110) is provided with a top cover (111). The top cover (111) has a liquid injection hole (112) that communicates with the inside of the battery cell (110). The injection hole (112) is connected to an exhaust branch pipe (121), and each exhaust branch pipe (121) is provided with a control valve, which is used to control the opening and closing of the exhaust branch pipe (121).

2. The battery module (100) according to claim 1, characterized in that The battery module (100) also includes a manifold (122), and one end of each of the exhaust branches (121) away from the liquid injection hole (112) is connected to the manifold (122).

3. The battery module (100) according to claim 2, characterized in that The battery module (100) also includes an exhaust manifold (123), and the manifold (122) is connected to the exhaust manifold (123).

4. The battery module (100) according to claim 3, characterized in that The multiple battery cells (110) arranged in an array are provided with end plates (130) on both sides. The end plates (130) are provided with a connected mounting port (131) and mounting groove (132). The mounting port (131) is used to install the manifold (122), and the mounting groove (132) is used to install the exhaust manifold (123).

5. The battery module (100) according to claim 3, characterized in that At least one of the exhaust branch pipe (121), the manifold (122), and the exhaust main pipe (123) is a metal pipe.

6. The battery module (100) of claim 1, wherein, The exhaust branch pipe (121) is connected to the injection hole (112) through the exhaust connector (120), and the exhaust connector (120) is fixedly connected or detachably connected to the top cover (111) at the injection hole (112).

7. The battery module (100) according to claim 1, characterized in that, The injection holes (112) on the top cover (111) of adjacent cells (110) are staggered.

8. The battery module (100) according to claim 1, characterized in that, A heat insulation element (140) is provided between adjacent cells (110).

9. A battery module thermal runaway control system, characterized in that, The system includes a battery module (100) as described in any one of claims 1-8 and a gas extraction device, wherein the gas extraction device is connected to the exhaust branch pipe (121) and the gas extraction device is used to discharge the gas generated by the thermal runaway of the battery cell (110) through the corresponding exhaust branch pipe (121) when the battery cell (110) thermally runs away.

10. The battery module thermal runaway control system according to claim 9, characterized in that, The system also includes a controller, and a detection device is provided on the battery cell (110). The signal output terminal of the detection device is electrically connected to the signal input terminal of the controller, and the signal output terminal of the controller is electrically connected to the signal input terminal of the control valve. The detection device includes at least one of a temperature sensor, a voltage sensor, and a pressure sensor.

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