Battery module for preventing heat spread

Abstract

The application discloses a battery module capable of preventing heat spread, and relates to the technical field of batteries.The battery module comprises a module frame, a plurality of battery cells and a thermal runaway isolation plate, one side of the thermal runaway isolation plate is in contact with a surface where explosion-proof valves of the plurality of battery cells are located, and an exhaust passage is formed between the other side of the thermal runaway isolation plate and an inner wall surface of the module frame which is close to a side of the explosion-proof valves; the thermal runaway isolation plate comprises a base material and a plurality of blocking pieces; a plurality of exhaust holes corresponding to the explosion-proof valves of the plurality of battery cells are formed in the base material; the plurality of blocking pieces are separately connected with the plurality of exhaust holes in a detachable mode; and each blocking piece covers the explosion-proof valve at a corresponding position. When the blocking pieces are pushed away by gas pressure or mechanical thrust of a thermal runaway battery cell, the exhaust passage is opened, and meanwhile, the base material and the blocking pieces at other positions block the high-temperature gas from spreading to other battery cells. The battery module capable of preventing heat spread has an internal heat spread protection function, can directively discharge the gas and residues generated when the battery cell is in thermal runaway, and effectively prevents heat spread of a subsequent battery system.

Description

Technical Field

[0001] This application relates to the field of batteries, specifically to a battery module that prevents heat spread. Background Technology

[0002] Most existing battery modules employ thermal insulation materials to protect against thermal runaway. However, this protection has certain shortcomings. Specifically, most battery modules lack a separate thermal runaway venting channel, or the cell's explosion-proof valve is directly connected to this venting channel. In this structure, when a single cell experiences thermal runaway, high-temperature gases can easily diffuse through the cell's venting area to other cells, causing thermal propagation within the battery module and leading to thermal runaway within that module. Furthermore, thermal runaway can spread between battery modules, ultimately causing thermal runaway of the entire battery system. This not only damages the battery system's performance and lifespan but may also pose safety hazards such as fires. Utility Model Content

[0003] In view of this, the purpose of this application is to provide a battery module that prevents heat spread in order to solve the above-mentioned technical problems.

[0004] This application provides a battery module for preventing heat propagation, comprising: a module frame; multiple battery cells disposed within the module frame, each battery cell including an explosion-proof valve; and a thermal runaway isolation plate disposed within the module frame. One side of the thermal runaway isolation plate contacts the surface of the explosion-proof valves of the multiple battery cells, and the other side of the thermal runaway isolation plate is kept at a certain distance from the inner wall of the module frame near the explosion-proof valves by an isolation plate support member, forming an exhaust channel. The thermal runaway isolation plate includes a substrate and multiple blocking plates. The substrate has multiple exhaust holes corresponding to the explosion-proof valves of the multiple battery cells. The edges of the multiple blocking plates are detachably connected to the edges of the multiple exhaust holes, and each blocking plate covers the explosion-proof valve at the corresponding position.

[0005] In some alternative implementations, the separable connection includes at least one of the following: forming fine cracks or slits by pre-cutting, reducing the thickness of the connection by physical thinning, bonding with adhesive, forming an easy-tear line by mechanical indentation, or forming a weakening line by a heat-sealing process.

[0006] In some alternative implementations, the exhaust passage leads directly to the outside of the module frame, or the exhaust passage connects to the outside through an exhaust port opened on the module frame.

[0007] In some alternative implementations, each cell also includes a tab, with the tab and explosion-proof valve respectively located on different surfaces of the cell, and the tabs and explosion-proof valves of multiple cells facing different inner wall surfaces of the module frame.

[0008] In some alternative implementations, the battery cell is a cylindrical cell with tabs located at the top and an explosion-proof valve located at the bottom.

[0009] In some alternative implementations, multiple cells are stacked in multiple rows along the height direction, with the tabs and explosion-proof valves of the multiple cells facing the opposite inner wall surfaces of the module frame.

[0010] In some alternative implementations, the system further includes: multiple cold plates, with at least one cold plate between every two rows of cells; wherein thermally conductive adhesive is filled between the cold plates and the cells, as well as between adjacent cells.

[0011] In some alternative implementations, the module frame includes two end plates, two side plates, and a bottom plate arranged opposite each other. The two end plates, two side plates, and bottom plate are connected by bolts and enclose a cavity for accommodating other components.

[0012] In some optional implementations, the system also includes a CCS component electrically connected to multiple battery cells. The CCS component includes an FPC and a bus. The FPC is used for the acquisition and transmission of temperature and voltage signals of the battery cells, and the bus is used for series and parallel connections between the battery cells to realize current transmission.

[0013] In some alternative implementations, the CCS assembly also includes a support structure that is integrally connected to the module frame, and the support structure and / or the module frame are provided with limiting structures for restricting cell displacement.

[0014] Based on the above technical solution, the battery module for preventing thermal runaway provided in this application has a thermal runaway isolation plate installed within the module frame. When a cell experiences thermal runaway, the corresponding blocking plate on the thermal runaway isolation plate will be subjected to gas pressure or mechanical thrust generated inside the cell. When the blocking plate is pushed open, i.e., when the blocking plate separates from the substrate, the explosion-proof valve of the thermal runaway cell connects with the exhaust channel formed between the thermal runaway isolation plate and the inner wall of the module frame. High-temperature gas can then be directed to flow outside the battery module through the exhaust channel. Simultaneously, the substrate of the thermal runaway isolation plate and the blocking plates at other locations can prevent high-temperature gas from diffusing to other cells. In this way, thermal runaway protection within the battery module is achieved, and the gas and residue generated during cell thermal runaway can be directionally discharged, effectively preventing thermal runaway in the subsequent battery system. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a cross-sectional view of a battery module designed to prevent heat spread, as provided in an embodiment of this application.

[0017] Figure 2 This is a partial structural diagram of a battery module for preventing heat spread, provided as an embodiment of this application.

[0018] Figure 3 This is a schematic diagram of the structure of a thermal runaway isolation plate provided in an embodiment of this application.

[0019] Reference numerals: 100, Battery module; 10, Module frame; 11, Side plate; 12, Base plate; 20, Battery cell; 21, Tab; 22, Explosion-proof valve; 30, CCS module; 40, Cold plate; 50, Thermal runaway isolation plate; 51, Substrate; 52, Baffle plate; 60, Isolation plate support; 70, Thermally conductive adhesive; 80, Venting channel. Detailed Implementation

[0020] The specific embodiments of this application will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of this application, and not all of them. Based on the description of this application, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this application.

[0021] In the description of this application, unless otherwise expressly specified and limited, the terms "connection," "setup," "installation," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it 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 according to the specific circumstances.

[0022] The terms “upper,” “lower,” “left,” “right,” “front,” “back,” “center,” “top,” “bottom,” “inner,” “outer,” “vertical,” “horizontal,” “clockwise,” “counterclockwise,” “axial,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of description and simplification, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0023] The terms “first,” “second,” “third,” etc., are used only to distinguish elements with similar properties, and do not indicate or imply relative importance or a specific order, unless otherwise explicitly stated or limited.

[0024] The terms “comprising,” “including,” “having,” or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0025] The term "multiple" means two or more (including two).

[0026] The term "and / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three cases: A exists alone, A and B exist simultaneously, and B exists alone.

[0027] The terms "an embodiment," "as an example," and "in one implementation" refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which may be included in at least one embodiment or example of this application. These illustrative expressions do not necessarily refer to the same embodiment, nor are they independent or alternative embodiments mutually exclusive with other embodiments. Where there is no conflict, the embodiments and features described in these embodiments can be combined in a suitable manner.

[0028] Figure 1 This is a cross-sectional view of a battery module 100 for preventing heat spread, provided in an embodiment of this application. Figure 2 This is a partial structural diagram of a battery module 100 for preventing heat spread, provided in an embodiment of this application. Figure 1 and Figure 2 As shown, this application embodiment provides a battery module 100 for preventing heat propagation, including a module frame 10, a battery cell 20, a CCS component 30, a cold plate 40, a thermal runaway isolation plate 50, and an isolation plate support member 60.

[0029] The module frame 10 is a rectangular frame, typically consisting of two end plates, two side plates, a bottom plate, and a top plate. In practical applications, at least one plate can be omitted depending on the requirements. Each plate can be made of epoxy board, metal-based composite board, or other thermal insulation materials.

[0030] As an example, the module frame 10 includes two end plates (not shown in the figure) arranged opposite each other, two side plates 11 arranged opposite each other, and a bottom plate 12. The two end plates, two side plates 11 and bottom plate 12 are connected by bolts and enclose a cavity to form an accommodating cavity. The battery cell 20, CCS assembly 30, cold plate 40, thermal runaway isolation plate 50 and isolation plate support member 60 are all disposed in the accommodating cavity.

[0031] The battery cell 20 adopts a thermoelectric separation design, featuring tabs 21 and explosion-proof valves 22 located on different surfaces. For example, the tabs 21 can be located on the top of the battery cell 20, and the explosion-proof valves 22 can be located on the bottom or side of the battery cell 20. This design can significantly reduce the possibility of electrical short circuits caused by ejected material in the event of thermal runaway of the battery cell 20. The battery cell 20 can be a square cell or a cylindrical cell, and there can be multiple cells. Multiple cells 20 are stacked within the module frame 10, wherein the surfaces of the tabs 21 of the multiple cells 20 face one inner wall of the module frame 10, and the surfaces of the explosion-proof valves 22 of the multiple cells 20 face another inner wall of the module frame 10.

[0032] As an example, cell 20 is a cylindrical cell, and its tabs 21 (see...) Figure 1 ) and explosion-proof valve 22 (see Figure 2 The cells 20 are located at the top and bottom of the cell 20, respectively; multiple cells 20 are stacked in multiple rows along the height direction within the accommodating cavity of the module frame 10, wherein the surfaces of the tabs 21 of these cells 20 face a side plate 11. Figure 1 The side plate 11 located on the left side of the battery cells 20, whose explosion-proof valves 22 are located on the same surface, faces the other side plate 11. Figure 1 The side panel 11 is located on the right side.

[0033] The CCS assembly 30 is electrically connected to the tabs 21 of multiple battery cells 20. Specifically, the CCS assembly 30 includes an FPC (Flexible Printed Circuit) (not shown in the figure) and a bus (not shown in the figure). The FPC is used for the acquisition and transmission of temperature and voltage signals of the battery cells 20, and the bus is used for the series and parallel connection between the battery cells 20 to realize current transmission.

[0034] The CCS assembly 30 also includes a support structure (not shown in the figure), such as an injection-molded bracket or a vacuum-formed isolation plate. The support structure can be connected to the module frame 10 by means of snap-fit, hot riveting, gluing, bolting, etc., to form an integrated structure. The support structure of the CCS assembly 30 and / or the module frame 10 may be provided with grooves, protrusions or other limiting structures to limit the displacement of the battery cells 20 and ensure the stable arrangement of the battery cells 20.

[0035] As an example, considering the case where the battery cell 20 is a cylindrical battery cell and multiple battery cells 20 are stacked along the height direction within the accommodating cavity of the module frame 10, the support structure of the CCS component 30 is connected to a side plate 11 of the module frame 10 by a snap-fit ​​mechanism. Figure 1 The side plate 11 located on the left side is connected as a whole. The support structure is provided with multiple first grooves, which are used to precisely limit and electrically isolate each battery cell 20. The side plate 11 is provided with multiple second grooves, which are used to position each battery cell 20 as a whole. The multiple first grooves and multiple second grooves together realize the limiting function of each battery cell 20.

[0036] The cold plate 40 contacts the battery cell 20 for heat dissipation, and thermally conductive adhesive 70 is filled between the cold plate 40 and the battery cell 20. For cylindrical battery cells, as an example, ... Figure 1 As shown, there are multiple cold plates 40, which are arranged parallel to each other along the height direction within the accommodating cavity of the module frame 10. One cold plate 40 is placed between every two rows of battery cells 20, ensuring that each row of battery cells 20 is in contact with the cold plate 40. Thermally conductive adhesive 70 is filled between the cold plate 40 and the battery cells 20, as well as between adjacent battery cells 20. Figure 1 The section marked with an index shows a cross-section of the thermally conductive adhesive 70 between adjacent cells 20 in the same row. The ends of multiple cold plates 40 can be connected via pipes, connectors, or connecting structures, allowing the flow channels of the multiple cold plates 40 to be connected in parallel or series. For square cells, cold plates 40 can be installed at the bottom or side of the module frame 10, with the cold plates 40 directly contacting the bottom or side of the cell 20 via the thermally conductive adhesive 70.

[0037] A thermal runaway isolation plate 50 is disposed between the surface of the explosion-proof valves 22 of the multiple battery cells 20 and the inner wall surface of the module frame 10 near the explosion-proof valves 22. Specifically, one side of the thermal runaway isolation plate 50 is in direct contact with the surface of the explosion-proof valves 22 of the multiple battery cells 20, and the other side of the thermal runaway isolation plate 50 is supported by multiple spaced isolation plate supports 60 to maintain a certain distance from the corresponding inner wall surface of the module frame 10. These isolation plate supports 60 can ensure the stable fixation of the thermal runaway isolation plate 50 and form a uniform gap, thereby forming an exhaust channel 80. This exhaust channel 80 is used to discharge high-temperature gases or other harmful substances generated when the battery cells 20 experience thermal runaway, and its minimum width should meet the design requirements to ensure that the gases can be discharged quickly. The exhaust channel 80 can lead directly to the outside of the module frame 10, which is suitable for scenarios with a high risk of thermal runaway; or it can be connected to the outside through an exhaust port opened on the module frame 10, which is suitable for scenarios that require additional control of the exhaust path. The specific choice depends on the design requirements and safety assessment results of the battery module 100.

[0038] Among them, the thermal runaway isolation plate 50 can be made of thermal insulation materials such as ceramic fiber board and glass fiber composite material; the isolation plate support 60 can be made of thermal insulation materials such as fireproof foam and phenolic foam, and its shape can be a block.

[0039] Figure 3 This is a schematic diagram of the structure of a thermal runaway isolation plate 50 provided in an embodiment of this application, as shown below. Figure 3 As shown, the thermal runaway isolation plate 50 includes a substrate 51 and multiple blocking plates 52. The substrate 51 has multiple vent holes corresponding to the explosion-proof valves 22 of the multiple battery cells 20. Each blocking plate 52 corresponds to one of the multiple vent holes, and the edge of each blocking plate 52 is detachably connected to the edge of its corresponding vent hole, with the blocking plate 52 covering the explosion-proof valve 22 at the corresponding position. When the blocking plate 52 is subjected to gas pressure or mechanical thrust generated inside the battery cell 20, causing its edge to separate from the edge of its corresponding vent hole, the vent hole is opened, and the explosion-proof valve 22 of the battery cell 20 communicates with the exhaust channel 80 through this vent hole.

[0040] Separable connections include, but are not limited to: forming fine cracks or slits through pre-cutting; reducing the thickness of the connection through physical thinning; connecting with adhesives; forming easy-tear lines through mechanical indentation; and forming weakening lines through heat sealing processes.

[0041] As an example, in the case where the battery cell 20 is a cylindrical battery cell and multiple battery cells 20 are stacked in multiple rows along the height direction in the accommodating cavity of the module frame 10, multiple rows of vent holes are opened on the substrate 51. Each vent hole in each row is circular and corresponds to the explosion-proof valve 22 of the battery cell 20. The shape of the blocking plate 52 is also circular. The edge of each blocking plate 52 and the edge of the corresponding vent hole are pre-cut to form a small cut.

[0042] The working principle of this battery module 100 to prevent thermal runaway is as follows: When a cell 20 experiences thermal runaway, the corresponding blocking plate 52 on the thermal runaway isolation plate 50 will be subjected to gas pressure or mechanical thrust generated inside the cell 20. Since the blocking plate 52 and the substrate 51 are designed to be separable, when the blocking plate 52 is pushed open by the gas pressure or mechanical thrust generated inside the cell 20, the corresponding vent hole of the blocking plate 52 is opened. At this time, the explosion-proof valve 22 of the cell 20 is connected to the venting channel 80 formed between the thermal runaway isolation plate 50 and the inner wall of the module frame 10 through the vent hole. High-temperature gas can flow directionally outside the battery module 100 through the venting channel 80. Simultaneously, the substrate 51 of the thermal runaway isolation plate 50 and the blocking plates 52 at other locations can prevent high-temperature gas from spreading to other cells 20. In this way, thermal runaway protection is achieved inside the battery module 100, and the gas and residue generated during cell thermal runaway can be directionally discharged, effectively preventing thermal runaway in the subsequent battery system.

[0043] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this application, and these should all be included within the scope of protection of this application.

Claims

1. A battery module with heat propagation prevention, characterized in that, include: Module framework; Multiple battery cells are disposed within the module frame, and each battery cell includes an explosion-proof valve; A thermal runaway isolation plate is disposed within the module frame. One side of the thermal runaway isolation plate is in contact with the surface where the explosion-proof valves of the multiple battery cells are located. The other side of the thermal runaway isolation plate is kept at a certain distance from the inner wall surface of the module frame near the explosion-proof valve through the isolation plate support member, forming an exhaust channel. The thermal runaway isolation plate includes a substrate and multiple blocking plates. The substrate has multiple vent holes corresponding to the explosion-proof valves of the multiple battery cells. The edges of the multiple blocking plates are detachably connected to the edges of the multiple vent holes. Each blocking plate covers the explosion-proof valve at the corresponding position.

2. The battery module for preventing heat propagation according to claim 1, characterized in that, The separable connection includes at least one of the following: pre-cutting to form fine cracks or slits, reducing the thickness of the connection by physical thinning, bonding with adhesive, forming an easy-tear line by mechanical indentation, or forming a weakening line by heat sealing.

3. The battery module for preventing heat propagation according to claim 1, characterized in that, The exhaust channel leads directly to the outside of the module frame, or the exhaust channel is connected to the outside through an exhaust port opened on the module frame.

4. The battery module for preventing heat propagation according to claim 1, characterized in that, Each of the battery cells also includes a tab, and the tab and the explosion-proof valve are respectively disposed on different surfaces of the battery cell, with the tabs and explosion-proof valves of multiple battery cells facing different inner wall surfaces of the module frame.

5. The battery module for preventing heat propagation according to claim 4, characterized in that, The battery cell is a cylindrical battery cell, the tab is located at the top of the battery cell, and the explosion-proof valve is located at the bottom of the battery cell.

6. The battery module for preventing heat propagation according to claim 5, characterized in that, Multiple battery cells are stacked in multiple rows along the height direction, with the tabs and explosion-proof valves of the multiple battery cells facing the opposite inner wall surfaces of the module frame.

7. The battery module for preventing heat propagation according to claim 6, characterized in that, Also includes: Multiple cold plates, with at least one cold plate between every two rows of the battery cells; Thermally conductive adhesive is used to fill the space between the cold plate and the battery cell, as well as between adjacent battery cells.

8. The battery module for preventing heat propagation according to claim 1, characterized in that, The module frame includes two end plates, two side plates, and a bottom plate arranged opposite each other. The two end plates, the two side plates, and the bottom plate are connected by bolts and enclose a cavity for accommodating other components.

9. The battery module for preventing heat propagation according to claim 1, characterized in that, Also includes: The CCS component is electrically connected to multiple battery cells. The CCS component includes an FPC and a bus. The FPC is used for the acquisition and transmission of temperature and voltage signals of the battery cells, and the bus is used for the series and parallel connection between the battery cells to realize current transmission.

10. The battery module for preventing heat propagation according to claim 9, characterized in that, The CCS component also includes a support structure, which is integrated with the module frame. The support structure and / or the module frame are provided with a limiting structure for restricting the displacement of the battery cell.

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