Battery case and battery pack

Abstract

A battery case and a battery pack. The battery case comprises a case body (1), a bottom protection plate (2), a holder (3) and a suction cup (4), wherein the case body (1) has an accommodating cavity (11); an opening in communication with the accommodating cavity (11) is provided in one side of the case body (1) in a first direction; the bottom protection plate (2) is detachably connected at the opening; the holder (3) is mounted on a cavity wall of the accommodating cavity, and the holder (3) and the bottom protection plate (2) are spaced apart to form a pressure relief channel (12); the pressure relief channel (12) is configured to relieve the pressure from gas generated by the thermal runaway of a battery cell assembly on the holder (3); and the suction cup (4) is provided on the side of the holder (3) facing the bottom protection plate (2), and the suction cup (4) abuts against the bottom protection plate (2).

Description

Battery boxes and battery packs

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on March 28, 2024, with application number 202420636011.8. The entire contents of the above application are incorporated by reference into this application.

[0002] Technical Field

[0003] The present application relates to the field of battery technology, for example, to a battery box and a battery pack.

[0004] Background Art

[0005] With the rapid development of the new energy vehicle industry, lithium battery modules are widely used in new energy vehicles. Lithium battery modules include a battery case and a cell module. The cell module is installed in the battery case. In order to prevent the safety of other cells in the lithium battery module from being affected by thermal runaway of individual cells, a corresponding thermal runaway design is usually configured. In related technologies, the thermal runaway design of lithium battery modules is to set a pressure relief channel on the battery case to quickly discharge the thermal runaway gas of a single cell, thereby preventing the thermal runaway from affecting other cells.

[0006] Technical issues

[0007] The pressure relief channel is usually formed by the tray supporting the battery cell module and the bottom guard plate of the battery box. Only the edge of the bottom guard plate is connected to the frame of the box, and the middle part of the bottom guard plate is suspended in the air, and the connection strength and impact strength are poor.

[0008] Technical Solutions

[0009] In the first aspect, an embodiment of the present application provides a battery box, comprising a box body, a bottom guard plate, a bracket and a suction cup, the box body having a accommodating cavity, an opening communicating with the accommodating cavity being provided on one side of the box body along a first direction, the bottom guard plate being detachably connected to the opening, the bracket being mounted on the cavity wall of the accommodating cavity, and a pressure relief channel being formed between the bracket and the bottom guard plate, the pressure relief channel being configured to relieve the thermal runaway gas of the battery cell assembly on the bracket, the suction cup being provided on the side of the bracket facing the bottom guard plate, and the suction cup being in contact with the bottom guard plate.

[0010] In a second aspect, an embodiment of the present application provides a battery pack, comprising a cell assembly and a battery box according to the first aspect, wherein the cell assembly is mounted on a bracket of the battery box, and the cell assembly is located on a side of the bracket away from the bottom guard plate.

[0011] Beneficial effects

[0012] In some embodiments of the present application, by arranging a detachable connection between the bottom guard plate and the box body, the production convenience of the battery box can be effectively improved, and the subsequent replacement of the bottom guard plate is facilitated, thereby reducing the maintenance cost of the battery box; the bracket is connected to the bottom guard plate by a suction cup, which is convenient for disassembly and assembly, and effectively improves the connection strength of the middle area of ​​the bottom guard plate. The support of the bottom guard plate by the suction cup can also improve the resistance of the bottom guard plate and reduce the deformation of the bottom guard plate under external impact. When the thermal runaway gas of the battery cell assembly enters the pressure relief channel, the increase in air pressure in the pressure relief channel enables the suction cup to be separated from the connection with the bottom guard plate. The bottom guard plate bulges outward in the direction away from the bracket under the push of the air pressure of the thermal runaway gas to increase the volume of the pressure relief channel, thereby improving the safety of the battery box.

[0013] BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG1 is a schematic structural diagram of a battery box according to some implementations of the present application;

[0015] FIG2 is a cross-sectional view of a battery box according to some implementations of the present application;

[0016] FIG3 is a schematic diagram of a partial structure of a battery box in some implementations of the present application.

[0017] In the picture:

[0018] 1. Box body; 11. Accommodating chamber; 12. Pressure relief channel; 13. Exhaust port; 14. Guide groove; 2. Bottom guard plate; 3. Bracket; 31. Connecting hole; 32. Connecting slot; 33. Support part; 4. Suction cup; 5. Pressure plate.

[0019] Modes for Carrying Out the Invention

[0020] The embodiments of the present application will be described below in conjunction with the accompanying drawings. The described embodiments are some related embodiments of the present application.

[0021] In the description of this application, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and can refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0022] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first feature being in direct contact with the second feature, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or may indicate that the first feature is at a higher level than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly below and obliquely below the second feature, or may indicate that the first feature is at a lower level than the second feature.

[0023] The embodiments of the present application provide a battery box and a battery pack, which have a simple structure and high connection strength and impact strength of the bottom guard plate.

[0024] As shown in Figures 1 and 2, the battery box of an embodiment of the present application includes a box body 1, a bottom guard plate 2, a bracket 3 and a suction cup 4. The box body 1 has a accommodating cavity 11. An opening communicating with the accommodating cavity 11 is provided on one side of the box body 1 along the first direction. The bottom guard plate 2 is detachably connected to the opening. The bracket 3 is installed on the cavity wall of the accommodating cavity 11, and the bracket 3 and the bottom guard plate 2 are spaced apart to form a pressure relief channel 12. The pressure relief channel 12 is configured to relieve the thermal runaway gas of the battery cell assembly on the bracket 3. A suction cup 4 is provided on the side of the bracket 3 facing the bottom guard plate 2, and the suction cup 4 is in contact with the bottom guard plate 2.

[0025] When the battery box is in normal use, the bottom guard plate 2 is located at the bottom, and the first direction is the height direction. By detachably connecting the bottom guard plate 2 and the box body 1, that is, splitting a complex integral component into multiple simple parts for production, the production convenience of the battery box can be effectively improved, and it is convenient to replace the bottom guard plate 2 when it is damaged by impact, thereby reducing the maintenance cost of the battery box; the bracket 3 is connected to the bottom guard plate 2 by using the suction cup 4. On the one hand, it is convenient to disassemble and assemble, and compared with detachable connection methods such as bolt connection, the connection is convenient, the operation intensity is reduced, and the sealing performance at the connection position is good, which ensures the sealing performance of the pressure relief channel 12 and reduces moisture or other impurities from entering the battery box and affecting the battery cells. The component is used normally; on the other hand, it can effectively improve the connection strength of the middle area of ​​the bottom guard plate 2, and the support of the suction cup 4 to the bottom guard plate 2 can also improve the impact strength of the bottom guard plate 2, that is, when the bottom guard plate 2 is impacted by the outside, the supporting force provided by the suction cup 4 can alleviate part of the impact force, reduce the deformation of the bottom guard plate 2 under the external impact, and when the thermal runaway gas of the battery cell component enters the pressure relief channel 12, the increase in the air pressure in the pressure relief channel 12 enables the suction cup 4 to be separated from the connection with the bottom guard plate 2, and the bottom guard plate 2 bulges outward in the direction away from the bracket 3 under the push of the air pressure of the thermal runaway gas, so as to increase the volume of the pressure relief channel 12, thereby improving the safety of the battery box.

[0026] For example, a first threaded hole is provided at the bottom of the box body 1, and a plurality of first through holes are provided on the bottom guard plate 2. A first bolt is passed through the first through hole and screwed into the first threaded hole to connect the bottom guard plate 2 to the box body 1. The threaded connection is convenient for assembly and disassembly and provides a stable connection. In other embodiments, a buckle can be provided on the bottom guard plate 2 and a slot can be provided on the box body 1, and the buckle and the slot can be connected by means of a snap connection.

[0027] In some embodiments, as shown in Figures 2 and 3, a plurality of communication holes 31 are provided through the bracket 3. The number of communication holes 31 corresponds to the number of cells in the battery assembly, and the communication holes 31 are arranged directly opposite the explosion-proof valves of the battery cells. The provision of communication holes 31 allows the gas generated when a battery cell experiences thermal runaway to be quickly transferred to the pressure relief channel 12. Each battery cell's pressure relief valve is provided with a corresponding communication hole 31, shortening the pressure relief distance and reducing the impact of the high temperature spread of thermal runaway gas on other battery cells.

[0028] In some embodiments, as shown in Figures 2 and 3 , a plurality of insertion slots 32 are recessed on one side of the bracket 3 away from the bottom guard plate 2 . Communication holes 31 extend through the bottoms of the insertion slots 32 , which are configured to accommodate battery cells. The insertion slots 32 facilitate positioning of the battery cells during installation on the bracket 3 , improving the accuracy of cell installation. Furthermore, the walls of the insertion slots 32 define the perimeter of the battery cells, enhancing the connection strength of the installed cells.

[0029] In some embodiments, as shown in FIG2 , the bracket 3 is provided with a plurality of support portions 33 protruding at intervals toward one side of the bottom guard plate 2, and each support portion 33 is provided with at least one suction cup 4. The provision of the support portions 33 ensures that the bottom guard plate 2 and the bracket 3 are spaced apart from each other, and the suction cup 4 is connected to the bottom guard plate 2, thereby strengthening the support provided by the bracket 3 to the suction cup 4.

[0030] In some embodiments, as shown in FIG1 , an exhaust port 13 is provided on the housing 1 , and the exhaust port 13 is connected to the pressure relief channel 12 . The provision of the exhaust port 13 allows the thermal runaway gas generated by the battery cell to be quickly discharged outside the housing 1 , thereby preventing the thermal runaway gas from accumulating and exploding within the pressure relief channel 12 . In this embodiment, the exhaust port 13 is provided on the side wall of the housing 1 . Compared to providing the exhaust port 13 on the bottom guard plate 2 , this prevents the exhaust port 13 from facing the ground during daily use, thereby reducing the possibility of impurities or moisture entering the pressure relief channel 12 .

[0031] In some embodiments, the battery case further includes an explosion-proof disc configured to block the exhaust port 13. The explosion-proof disc can rupture when the thermal runaway gas reaches a certain pressure, thereby opening the exhaust port 13 and allowing the pressure relief passage 12 to communicate with the outside. The explosion-proof disc can block the exhaust port 13 during daily use, ensuring the tightness of the pressure relief passage 12 and preventing external impurities from entering the pressure relief passage 12 and affecting the use of the battery cells, thereby improving the safety of the battery case 1.

[0032] In some embodiments, the thickness of the explosion-proof plate at the center is less than the thickness at the edge. This design can ensure the connection strength between the explosion-proof plate and the box body 1, and can also enable the explosion-proof plate to explode preferentially from the weak area under the impact of thermal runaway gas, thereby ensuring the safety of the explosion-proof plate.

[0033] In some embodiments, the bracket 3 is detachably connected to the wall of the accommodating chamber 11. This detachable arrangement facilitates the production of the battery box, reducing production costs. Furthermore, during subsequent maintenance, the bracket 3 and the housing 1 can be replaced separately, resulting in low maintenance costs. In this embodiment, a second through hole is provided on the bracket 3, and a second threaded hole is provided on the housing 1. A second bolt passes through the second through hole and is screwed into the second threaded hole, thereby fixing the bracket 3 to the housing 1, providing a secure connection and ensuring the stability of the bracket 3 connection. In other embodiments, the bracket 3 can also be connected by other detachable means such as snap-fitting.

[0034] In some embodiments, a guide groove 14 is recessed in the wall of the accommodating cavity 11, and the length of the guide groove 14 extends along the first direction. The bracket 3 is provided with a guide portion, which is inserted into the guide groove 14. The cooperation between the guide portion and the guide groove 14 can enhance the guidance of the bracket 3 during installation, thereby improving the installation accuracy of the bracket 3.

[0035] As shown in Figures 1 to 3, embodiments of the present application further provide a battery pack comprising a cell assembly and a battery box according to any of the above embodiments. The cell assembly is mounted on a bracket 3 of the battery box, with the cell assembly located on a side of the bracket 3 away from the bottom guard plate 2. In the battery pack, the bracket 3 and the bottom guard plate 2 are separated to form a pressure relief channel 12 to facilitate the discharge of gas from the battery cells during thermal runaway, thereby improving the safety of the battery pack.

[0036] In some embodiments, the battery pack further includes a pressure plate 5. A mounting opening communicating with the accommodating cavity 11 of the battery box 1 is provided on the side of the battery box body 1 away from the bottom guard plate 2. A pressure plate 5 is provided at the mounting opening, and the pressure plate 5 is configured to press against the battery cell assembly. It is understandable that the installation order of the battery cell module is as follows: first, the bottom guard plate 2 is installed on the box body 1 to block the opening of the box body 1, and then the bracket 3 provided with the battery cell assembly is installed into the accommodating cavity 11. During installation, it is only necessary to install the bracket 3 and adsorb the suction cup 4 onto the bottom guard plate 2 to complete the reinforced connection of the middle position of the bottom guard plate 2. Finally, the pressure plate 5 is installed into the box body 1 to press against the battery cell assembly to ensure the installation stability of the battery cell assembly.

[0037] In some embodiments, an avoidance hole is provided on the pressure plate 5 corresponding to the position of the protruding pole of each battery cell in the battery cell assembly. The setting of the avoidance hole reduces the space occupied by the protruding pole of the battery cell, improves the space utilization in the accommodating cavity 11, and the restriction of the hole wall of the avoidance hole on the pole can enhance the installation stability of the battery cell.

[0038] In some embodiments, during the battery pack assembly process, potting glue can be injected into the pressing plate 5 and the bracket 3 to enhance the installation stability of the battery cell assembly and the thermal insulation between the battery cells.

[0039] In some embodiments, a cold gel pad may be further provided on the side of the bottom guard plate 2 facing the bracket 3 . The cold gel pad has good thermal conductivity and can accelerate the heat dissipation of the battery cell assembly or the cooling of the thermal runaway gas.

[0040] In the description of this article, it should be understood that the terms "upper", "lower" and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation.

[0041] In the description of this specification, the description of reference terms such as "embodiment" means that the specific features, structures, materials or characteristics of the embodiment are included in at least one embodiment or example of the present application. In this specification, the schematic representation of terms does not necessarily refer to the same embodiment.

[0042] In addition, it should be understood that although this specification is described in terms of implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. A battery box, comprising a box body, a bottom guard plate, a bracket and a suction cup, the box body having a accommodating cavity, a side of the box body along a first direction is provided with an opening communicating with the accommodating cavity, the bottom guard plate is detachably connected to the opening, the bracket is mounted on the cavity wall of the accommodating cavity, and the bracket and the bottom guard plate are spaced to form a pressure relief channel, the pressure relief channel is configured to relieve thermal runaway gas of the battery cell assembly on the bracket, the suction cup is provided on a side of the bracket facing the bottom guard plate, and the suction cup abuts against the bottom guard plate.

2. The battery box according to claim 1, wherein: The bracket is provided with a plurality of communication holes, the number of the communication holes corresponds to the number of the battery cells of the battery cell assembly, and the communication holes are arranged opposite to the explosion-proof valves of the battery cells.

3. The battery box according to claim 2, wherein: A plurality of plug-in slots are recessed on one side of the bracket away from the bottom guard plate, the connecting holes are arranged through the bottoms of the plug-in slots, and the plug-in slots are arranged to supply the battery cells.

4. The battery box according to any one of claims 1 to 3, wherein: The bracket is provided with a plurality of support parts protruding at intervals toward one side of the bottom guard plate, and each of the support parts is provided with at least one suction cup.

5. The battery box according to any one of claims 1 to 3, wherein: An exhaust port is provided on the box body, and the exhaust port is communicated with the pressure relief channel.

6. The battery box according to claim 5, further comprising an explosion-proof plate, wherein the explosion-proof plate is configured to block the exhaust port.

7. The battery box according to any one of claims 1 to 3, wherein: The bracket is detachably connected to the cavity wall of the accommodating cavity.

8. The battery box according to claim 7, wherein: A guide groove is recessed on the cavity wall of the accommodating cavity, and the length of the guide groove extends along the first direction. A guide portion is provided on the bracket, and the guide portion is inserted into the guide groove.

9. A battery pack, comprising a battery cell assembly and a battery box as described in any one of claims 1 to 8, wherein the battery cell assembly is mounted on a bracket of the battery box, and the battery cell assembly is located on a side of the bracket away from the bottom guard plate.

10. The battery pack according to claim 9 further includes a pressure plate, and a mounting opening communicating with the accommodating cavity of the box body is provided on a side of the box body of the battery box away from the bottom guard plate, and the pressure plate is provided at the mounting opening, and the pressure plate is configured to press against the battery cell assembly.

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