Battery pack

Abstract

Provided in the present application is a battery pack, comprising a case body (1), a battery module (2), a maintenance cover (3) and a fire extinguisher (4). An accommodating cavity (11) for accommodating the battery module is provided in the case body (1), and the case body (1) is provided with a maintenance port (13). The maintenance cover (3) is configured to seal the maintenance port (13), and the maintenance cover (3) comprises a bottom plate (31), a support portion (32) and a connection portion (33), wherein a support portion (32) is provided around the outer edge of the bottom plate (31) on the side of the bottom plate (31) facing the battery module, and the support portion (32) encloses a mounting cavity (34) for accommodating the fire extinguisher (4); and the connection portion (33) is provided on the peripheral wall of the support portion (32), and the connection portion (33) is detachably connected to the case body (1).

Description

Battery pack

[0001] This application claims priority to Chinese Patent Application No. 202521133431.5, filed with the Chinese Patent Office on June 4, 2025, the entire contents of which are incorporated herein by reference.

[0002] Technical Field

[0003] This application relates to the field of battery technology, specifically to a battery pack.

[0004] Background Technology

[0005] With the increasing development of new energy sources, battery energy storage technology has become a key technology. The basic structure of battery energy storage is a battery pack, which consists of a battery box and multiple battery modules built into the battery box. During the charging and discharging process of the battery modules, a large amount of heat is generated, so air cooling or liquid cooling is required to dissipate heat and reduce the possibility of thermal runaway.

[0006] Technical issues

[0007] As battery pack energy density increases, fire safety protection against thermal runaway becomes increasingly important. For traditional battery packs, if fire-fighting devices need to be installed inside the battery box, it will squeeze the space of the battery modules and affect the battery pack capacity.

[0008] Technical solutions

[0009] In a first aspect, embodiments of this application provide a battery pack, including a housing, a battery module, a maintenance cover, and a fire extinguisher. The housing has a receiving cavity for accommodating the battery module. The housing has mounting surfaces arranged along a first direction. The mounting surfaces have a maintenance opening communicating with the receiving cavity. The maintenance cover is configured to block the maintenance opening. The maintenance cover includes a base plate, a support portion, and a connecting portion. The support portion is arranged around the outer edge of the base plate on the side facing the battery module. The support portion encloses and forms a mounting cavity for accommodating the fire extinguisher. The connecting portion is arranged around the outer edge of the outer peripheral wall of the support portion, and the connecting portion is adjacent to the side of the support portion away from the base plate. The connecting portion is detachably connected to the housing.

[0010] Beneficial effects

[0011] By providing a maintenance port on the mounting surface of the enclosure, the detachable maintenance cover can be easily opened to access and maintain the battery modules and other components inside the enclosure. The maintenance cover is easy to install and remove, effectively improving the convenience and efficiency of battery pack maintenance. Furthermore, by providing a ring-shaped support on the bottom plate of the maintenance cover to form an enclosure for accommodating fire extinguishers, the fire extinguishers are kept separate from the battery modules, preventing them from occupying the battery module's storage space and ensuring the battery pack's capacity. The rational layout of the fire extinguishers also enhances the battery pack's fire protection capabilities and improves its overall safety.

[0012] Attached Figure Description

[0013] Figure 1 is a schematic diagram of the structure of the battery pack according to an embodiment of this application;

[0014] Figure 2 is an exploded schematic diagram of the battery pack according to an embodiment of this application;

[0015] Figure 3 is a schematic diagram of the structure of the maintenance cover according to an embodiment of this application;

[0016] Figure 4 is a cross-sectional view of the maintenance cover according to an embodiment of this application;

[0017] Figure 5 is a schematic diagram of the cooperation between the maintenance cover and the fire extinguisher according to an embodiment of this application;

[0018] Figure 6 is an explosion diagram of the maintenance cover and fire extinguisher according to an embodiment of this application.

[0019] In the picture:

[0020] 1. Housing; 11. Receiving cavity; 12. Mounting surface; 13. Maintenance port; 2. Battery module; 3. Maintenance cover; 31. Base plate; 32. Support part; 33. Connecting part; 331. First through hole; 332. First limiting groove; 333. Second limiting groove; 34. Mounting cavity; 35. Mounting column; 36. Pressure relief hole; 361. First explosion-proof hole; 362. Second explosion-proof hole; 37. First reinforcing rib; 38. Weight reduction groove; 4. Fire extinguisher; 5. First sealing ring; 6. Second sealing ring; 7. Explosion-proof valve.

[0021] Embodiments of the present invention

[0022] As shown in Figures 1 to 6, the battery pack of this embodiment includes a housing 1, a battery module 2, a maintenance cover 3, and a fire extinguisher 4. The housing 1 has a receiving cavity 11 for accommodating the battery module 2. The housing 1 has mounting surfaces 12 arranged along a first direction (the first direction is the X direction shown in the figure). The mounting surfaces 12 have a maintenance opening 13 communicating with the receiving cavity 11. The maintenance cover 3 is configured to block the maintenance opening 13. The maintenance cover 3 includes a base plate 31, a support portion 32, and a connecting portion 33. A ring of support portions 32 is arranged around the outer edge of the base plate 31 on the side facing the battery module 2. The support portions 32 enclose... An installation cavity 34 for accommodating the fire extinguisher 4 is formed. A connecting portion 33 is provided around the outer edge of the support portion 32 on the outer peripheral wall of the support portion 32. That is, a supporting portion 32 is formed around the outer edge of the bottom plate 31 facing the battery module 2. The length of the supporting portion 32 extends along the first direction. A connecting portion 33 is formed around the outer edge of the support portion 32 on the outer peripheral wall of the support portion 32. The length of the connecting portion 33 extends along the thickness direction of the support portion 32. The connecting portion 33 is adjacent to the side of the support portion 32 away from the bottom plate 31. The connecting portion 33 is detachably connected to the housing 1.

[0023] By providing a maintenance port 13 on the mounting surface 12 of the housing 1, it is easy to open the detachable maintenance cover 3 and pass through the maintenance port 13 to inspect and maintain the battery module 2 and other components inside the housing 1. The maintenance cover 3 is easy to install and remove, which can effectively improve the maintenance convenience and efficiency of the battery pack. By providing an annular support part 32 on the bottom plate 31 of the maintenance cover 3 to form an installation cavity 34 for accommodating the fire extinguisher 4, it is possible to ensure that the fire extinguisher 4 is separated from the battery module 2, avoid the fire extinguisher 4 occupying the storage space of the battery module 2 inside the housing 1, ensure the capacity of the battery pack, and the reasonable layout of the fire extinguisher 4 can enhance the fire protection function of the battery pack and improve the overall safety of the battery pack.

[0024] In this embodiment, the maintenance cover 3 is integrally injection molded from insulating material, that is, the base plate 31, the support part 32, and the connecting part 33 are integrally injection molded. This results in high structural strength. Compared to traditional sheet metal parts, which require multiple processes such as bending, welding, and painting, integral injection molding offers higher production efficiency. Furthermore, the cost of insulating material is lower, and it is less prone to rust and corrosion. In addition, company names, structural markings, and other identification information can be directly injection molded onto the outer side of the base plate 31. The markings have high connection strength and are not easily detached, reducing the investment in traditional labels.

[0025] In some embodiments, as shown in Figures 2 and 3, the mounting surface 12 has multiple first connecting holes, all of which surround the maintenance port 13. The connecting part 33 has multiple first through holes 331. Bolts pass through the first through holes 331 and are screwed into the first connecting holes to connect the connecting part 33 to the housing 1. In this embodiment, the first connecting holes are threaded holes. The bolts pass through the first through holes 331 and are screwed into the threaded holes to achieve the connection. That is, the bolt screwing clamps the connecting part 33 between the bolt head and the housing 1. The bolt thread connection provides strong clamping force and can withstand high loads, ensuring the connection stability between the maintenance cover 3 and the housing 1 and reducing the risk of loosening or failure. The bolt connection is convenient to install and remove, and has low replacement costs.

[0026] As shown in Figures 4 and 5, the battery pack also includes a first sealing ring 5 and a second sealing ring 6. Both the first sealing ring 5 and the second sealing ring 6 are disposed between the connecting part 33 and the mounting surface 12, and both surround the maintenance opening 13. The first through hole 331 is located between the first sealing ring 5 and the second sealing ring 6. The two sealing rings effectively enhance the sealing between the maintenance cover 3 and the housing 1, thereby effectively preventing external moisture, dust, or other impurities from entering the battery pack and improving its sealing performance. Furthermore, the arrangement of the first sealing ring 5 and the second sealing ring 6 around the maintenance opening 13 is simple in structure and easier to install compared to a structure where each bolt has a sealing ring around its circumference. The first through hole 331 is located between the two sealing rings, meaning the bolt is located between the two sealing rings, effectively ensuring the sealing of the bolt's periphery and reducing the possibility of gaps in a single sealing ring or premature wear leading to a poor seal.

[0027] In some embodiments, as shown in FIG6, the connecting portion 33 is provided with a first limiting groove 332 and a second limiting groove 333 at intervals, and both the first limiting groove 332 and the second limiting groove 333 are arranged around the base plate 31. The first through hole 331 is located between the first limiting groove 332 and the second limiting groove 333. The first sealing ring 5 is partially inserted into the first limiting groove 332, and the second sealing ring 6 is partially inserted into the second limiting groove 333. By setting the limiting groove, the installation position accuracy of the sealing ring is effectively improved. Moreover, compared with a single surface abutting against the sealing ring, the groove wall and bottom of the limiting groove have a larger sealing contact surface with the sealing ring, resulting in a better sealing effect.

[0028] The first sealing ring 5 is positioned adjacent to the service port 13. The compression ratio of the first sealing ring 5 is C1, and the compression ratio of the second sealing ring 6 is C2, where C1 > C2. Since the battery module 2 generates heat during operation, causing an increase in air pressure within the receiving cavity 11, the first sealing ring 5, which is adjacent to the service port 13 and in contact with the receiving cavity 11, must adapt to the pressure changes within the receiving cavity 11 to ensure its sealing effect. Of course, the second sealing ring 6 is in contact with the atmosphere, and the material selection for the second sealing ring 6 should place greater emphasis on dustproofing and resistance to air humidity.

[0029] In some embodiments, as shown in FIG4, the cross-sectional diameter of the first sealing ring 5 is D1, and the cross-sectional diameter of the second sealing ring 6 is D2, where D1 > D2. The cross-sectional diameter is the outer diameter minus the inner diameter of the sealing ring. By increasing the cross-sectional diameter of the first sealing ring 5, the compressible deformation size of the first sealing ring 5 and the sealing contact surface are ensured, thus ensuring the sealing effect between the maintenance cover 3 and the housing 1. The second sealing ring 6 is in long-term contact with the external environment and is more prone to corrosion and aging. Therefore, the smaller size of the second sealing ring 6 can achieve double sealing protection, and the replacement cost of the second sealing ring 6 is lower, thus the maintenance cost is also lower than that of the traditional single-ring sealing method.

[0030] Furthermore, the cross-sectional diameter D of the first sealing ring 5 and the second sealing ring 6 satisfies: 0.2mm ≤ D ≤ 0.5mm. For example, the cross-sectional diameter D of the first sealing ring 5 and the second sealing ring 6 can be 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, etc. If the cross-sectional diameter of the sealing ring is too large, it occupies too much space, the connection part 33 will be wider, and the production cost will be high. If the cross-sectional diameter of the sealing ring is too small, it is easy to cause poor sealing, poor durability, and easy damage. The sealing rings in this design have moderate dimensions, good sealing effect, and long service life.

[0031] In some embodiments, as shown in Figures 5 and 6, a plurality of mounting posts 35 protrude from the base plate 31 toward the battery module 2, and the fire extinguisher 4 is detachably connected to the mounting posts 35. That is, a plurality of mounting posts 35 are integrally injection molded on the side of the base plate 31 toward the battery module 2, resulting in a stable, integrally formed structure that is easier to manufacture than traditional sheet metal welded nut posts. In this embodiment, the fire extinguisher 4 includes a fire extinguishing body, a detector, and a fire extinguishing agent. The fire extinguishing body has a plurality of second through holes, and the mounting posts 35 have second connection holes, i.e., second threaded holes. Bolts pass through the second through holes and are screwed into the second threaded holes to achieve a detachable connection between the fire extinguisher 4 and the mounting posts 35. The fire extinguishing body is equipped with a mechanism for detecting thermal runaway within the containment cavity 11, so that the triggering mechanism can promptly spray the fire extinguishing agent within the fire extinguishing body to extinguish the fire and achieve the fire extinguishing purpose. Of course, the fire extinguisher 4 can also be connected to liquid cooling media, external water sources, or pneumatic fire extinguishing structures via other pipes, and no limitations are imposed here.

[0032] As shown in Figures 1, 2, and 3, the battery pack also includes an explosion-proof valve 7. The maintenance cover 3 has a pressure relief hole 36 communicating with the receiving cavity 11, and the explosion-proof valve 7 is located at the pressure relief hole 36. The explosion-proof valve 7 is designed to allow high-pressure gas inside the battery pack to break through the valve and release pressure through the pressure relief hole 36 in the event of thermal runaway. This prevents gas accumulation or excessive internal pressure due to overcharging, overheating, or short circuits, thus improving the safety of the battery pack.

[0033] The explosion-proof valve 7 and the maintenance cover 3 are detachably connected. The battery pack also includes a third sealing ring, which is located between the explosion-proof valve 7 and the maintenance cover 3. A third limiting groove is provided on one side of the two adjacent sides of the explosion-proof valve 7 and the maintenance cover 3, and a limiting protrusion is provided on the other side. The third sealing ring is engaged between the limiting protrusion and the bottom of the third limiting groove. The explosion-proof valve 7 has multiple third through holes, and the maintenance cover 3 has multiple third threaded holes spaced around the pressure relief hole 36. Bolts are passed through the third through holes and screwed into the third threaded holes to achieve a detachable connection between the explosion-proof valve 7 and the maintenance cover 3. The threaded connection is secure, and the detachable connection between the explosion-proof valve 7 and the maintenance cover 3 also allows for maintenance in the event of thermal runaway of the battery pack, where only the explosion-proof valve 7 needs to be removed and replaced, reducing the maintenance cost of battery pack thermal runaway.

[0034] Of course, the third sealing ring effectively ensures the sealing of the connection between the explosion-proof valve 7 and the maintenance cover 3. In this embodiment, the explosion-proof valve 7 is connected to the base plate 31. A third limiting groove is arranged around the side of the explosion-proof valve 7 facing the base plate 31, and a limiting protrusion is arranged around the pressure relief hole 36 on the base plate 31. The third sealing ring is placed in the third limiting groove and clamped between the limiting protrusion and the bottom of the third limiting groove. On the one hand, this can enhance the installation and positioning accuracy of the third sealing ring, and on the other hand, it can increase the sealing contact area of ​​the third sealing ring and ensure the compression effect of the third sealing ring when the explosion-proof valve 7 is connected to the base plate 31, thereby ensuring the sealing effect of the third sealing ring.

[0035] In some embodiments, the pressure relief hole 36 includes a first explosion-proof hole 361 and a plurality of second explosion-proof holes 362 communicating with the first explosion-proof hole 361. All the second explosion-proof holes 362 are evenly distributed along the outer edge of the first explosion-proof hole 361. This structural layout of the pressure relief hole 36 can effectively ensure the pressure relief area. In this embodiment, the third threaded hole is disposed between two adjacent second explosion-proof holes 362, which not only ensures the pressure relief area but also effectively ensures the tightness of the fit between the third threaded hole and the pressure relief hole 36, reducing structural damage to the maintenance cover 3 and ensuring the structural strength of the maintenance cover 3.

[0036] In other embodiments, as shown in Figures 4, 5, and 6, multiple first reinforcing ribs 37 are spaced apart on the side of the base plate 31 away from the battery module 2. The length of the first reinforcing ribs 37 extends along a second direction (the second direction is the Y direction shown in the figure), and the first direction and the second direction are set at an angle. That is, multiple first reinforcing ribs 37 are integrally injection molded on the side of the base plate 31 away from the battery module 2. Since the maintenance cover 3 has a large area, the setting of the first reinforcing ribs 37 can strengthen the structural strength of the base plate 31, enhance the compressive strength, bending strength, and deformation resistance of the base plate 31, and reduce the possibility of damage to the battery module 2 or other components in the receiving cavity 11 due to deformation caused by external impact. Of course, multiple weight-reducing grooves 38 are provided on the side of the base plate 31 adjacent to the battery module 2, corresponding to the multiple first reinforcing ribs 37. The length of the weight-reducing grooves 38 extends along the second direction, and part of the weight-reducing grooves 38 extends into the first reinforcing ribs 37, so as to strengthen the structural strength of the maintenance cover 3 while reducing the weight of the overall structure.

[0037] In addition to the weight-reducing groove 38, the side of the base plate 31 adjacent to the battery module 2 can also have multiple second reinforcing ribs spaced apart. The length of the second reinforcing ribs extends along a third direction (the third direction is the Z direction shown in the figure), and the first and second directions are respectively set at angles with the third direction. By setting the second reinforcing ribs on the side of the base plate 31 adjacent to the battery module 2, and the second reinforcing ribs are set at an angle with the first reinforcing ribs 37, the structural strength of the base plate 31 can be strengthened, preventing the maintenance cover 3 from deforming or being damaged when the battery pack is subjected to external impact or pressure, thereby improving the overall pressure resistance and protection performance of the battery pack. Furthermore, the protrusion of the second reinforcing ribs can increase the heat exchange contact area between the base plate 31 and the high-temperature gas in the accommodating cavity 11, and the protrusion of the first reinforcing ribs 37 can increase the heat exchange area between the base plate 31 and the external environment, thereby improving the overall heat exchange effect between the maintenance cover 3 and the external environment.

Claims

1. A battery pack, comprising a housing (1), a battery module (2), a maintenance cover (3), and a fire extinguisher (4), wherein the housing (1) is provided with a receiving cavity (11) for accommodating the battery module (2), the housing (1) having a mounting surface (12) arranged along a first direction, the mounting surface (12) having a maintenance port (13) communicating with the receiving cavity (11), the maintenance cover (3) being configured to block the maintenance port (13), the maintenance cover (3) comprising a base plate (31), a support portion (32), and a connecting portion (33). A support portion (32) is provided around the outer edge of the base plate (31) facing the battery module (2). The support portion (32) forms an installation cavity (34) for accommodating the fire extinguisher (4). A connecting portion (33) is provided around the outer edge of the support portion (32) on the outer peripheral wall of the support portion (32). The connecting portion (33) is adjacent to the side of the support portion (32) away from the base plate (31). The connecting portion (33) is detachably connected to the housing (1).

2. The battery pack of claim 1, wherein, The mounting surface (12) is provided with a plurality of first connection holes, all of which are arranged around the maintenance port (13). The connecting part (33) is provided with a plurality of first through holes (331). Bolts are passed through the first through holes (331) and screwed into the first connection holes to realize the connection between the connecting part (33) and the housing (1).

3. The battery pack according to claim 2 further includes a first sealing ring (5) and a second sealing ring (6), the first sealing ring (5) and the second sealing ring (6) are both disposed between the connecting part (33) and the mounting surface (12), and the first sealing ring (5) and the second sealing ring (6) are both disposed around the maintenance port (13), and the first through hole (331) is located between the first sealing ring (5) and the second sealing ring (6).

4. The battery pack of claim 3, wherein, The connecting part (33) is provided with a first limiting groove (332) and a second limiting groove (333) at intervals, and the first limiting groove (332) and the second limiting groove (333) are both arranged around the bottom plate (31). The first through hole (331) is located between the first limiting groove (332) and the second limiting groove (333). The first sealing ring (5) is partially inserted into the first limiting groove (332), and the second sealing ring (6) is partially inserted into the second limiting groove (333).

5. The battery pack of claim 3, wherein, The first sealing ring (5) is disposed adjacent to the maintenance port (13), the compression ratio of the first sealing ring (5) is C1, the compression ratio of the second sealing ring (6) is C2, C1 > C2; and / or, The cross-sectional diameter of the first sealing ring (5) is D1, and the cross-sectional diameter of the second sealing ring (6) is D2, where D1 > D2; and / or, The cross-sectional diameter D of the first sealing ring (5) and / or the second sealing ring (6) satisfies: 0.2mm≤D≤0.5mm.

6. The battery pack of any one of claims 1-5, wherein, The base plate (31) has multiple mounting posts (35) protruding from the side facing the battery module (2), and the fire extinguisher (4) is detachably connected to the mounting posts (35).

7. The battery pack according to any one of claims 1-5 further includes an explosion-proof valve (7), wherein the maintenance cover (3) is provided with a pressure relief hole (36) communicating with the receiving cavity (11), and the explosion-proof valve (7) is provided at the pressure relief hole (36).

8. The battery pack of claim 7, wherein, The explosion-proof valve (7) is detachably connected to the maintenance cover (3). The battery pack also includes a third sealing ring. The third sealing ring is disposed between the explosion-proof valve (7) and the maintenance cover (3). A third limiting groove is provided on one side of the two adjacent sides of the explosion-proof valve (7) and the maintenance cover (3), and a limiting protrusion is provided on the other side. The third sealing ring is engaged between the limiting protrusion and the bottom of the third limiting groove.

9. The battery pack of claim 7, wherein, The pressure relief hole (36) includes a first explosion-proof hole (361) and a plurality of second explosion-proof holes (362) communicating with the first explosion-proof hole (361). All the second explosion-proof holes (362) are evenly distributed along the outer edge of the first explosion-proof hole (361).

10. The battery pack of any one of claims 1-5, wherein, The base plate (31) is provided with a plurality of first reinforcing ribs (37) at intervals on the side away from the battery module (2). The length of the first reinforcing ribs (37) extends along the second direction, and the first direction is set at an angle to the second direction.

11. The battery pack of claim 10, wherein, The base plate (31) is provided with multiple second reinforcing ribs at intervals on the side adjacent to the battery module (2). The length of the second reinforcing ribs extends along a third direction, and the first direction and the second direction are respectively set at an angle to the third direction.

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