Battery pack lower shell with exhaust channel and battery pack

Abstract

The utility model discloses a battery pack lower shell with an exhaust passage and a battery pack, and relates to the technical field of battery pack design, the battery pack lower shell is composed of a bottom plate and boundary beams vertically fixed along the periphery of the bottom plate, and a plurality of battery cells are sequentially and tightly placed in the lower shell; a plurality of exhaust holes are uniformly distributed in the inner side walls of the edge beams on the left side and the right side of the lower shell in sequence, and the exhaust holes directly face the battery cell explosion-proof valves on the two sides of the battery cell; exhaust channels are formed in the edge beams on the left side and the right side of the lower shell, and the exhaust holes communicate with the exhaust channels; a cavity communicated with the exhaust channel is formed in the front side edge beam or the rear side edge beam of the lower shell, and a hole is formed in the outer side wall of the front side edge beam or the rear side edge beam of the lower shell to install a battery pack anti-explosion valve. According to the utility model, the exhaust channel is reasonably designed in the lower shell of the battery pack, so that generated gas and foreign matters are discharged out of the battery pack in time, the risk caused by thermal runaway is reduced, and meanwhile, the cost can be controlled, the energy density is improved, and the product competitiveness is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery pack design, and particularly relates to a battery pack lower housing with an exhaust passage and a battery pack. Background Art

[0002] The statements herein only provide background art related to the utility model and do not necessarily constitute prior art.

[0003] With the rapid development of new energy technologies, lithium-ion power batteries are increasingly widely and commonly used in electric vehicles, and the safety performance of battery packs has received extensive attention. When lithium-ion power batteries are under conditions such as mechanical damage, thermal management failure, overcharging and over-discharging, they may trigger thermal runaway. When the battery cells experience thermal runaway, a large amount of high-temperature combustible mixed gas and foreign substances (such as electrolyte, dust, etc.) will be generated. If the gas cannot be discharged in time or the foreign substances block the explosion-proof valve of the battery pack, the air pressure inside the battery pack will rapidly increase, and even fire and explosion may occur, endangering the safety of the vehicle and passengers.

[0004] Currently, the existing battery pack designs often increase the distance between the explosion-proof valve of the battery cell and the side beam of the battery pack lower housing to increase the exhaust space. However, this method will increase the weight and cost of the lower housing, reduce the energy density of the battery pack, and the competitiveness of the corresponding products is relatively weak. Summary of the Utility Model

[0005] Aiming at the above problems and defects existing in the prior art, the utility model provides a battery pack lower housing with an exhaust passage and a battery pack. By reasonably designing the exhaust passage in the battery pack lower housing, the generated gas and foreign substances can be discharged from the battery pack in time, the risk of thermal runaway is reduced, the cost can be controlled, the energy density is improved, and the competitiveness of the product is enhanced.

[0006] To achieve the above object, the utility model adopts the following technical solutions:

[0007] In the first aspect, the utility model provides a battery pack lower housing with an exhaust passage.

[0008] A battery pack lower housing with an exhaust passage is composed of a bottom plate and side beams vertically fixed along the four sides of the bottom plate. A plurality of battery cells are sequentially and closely placed inside the lower housing.

[0009] A plurality of exhaust holes are sequentially and evenly arranged on the inner side walls of the side beams on the left and right sides of the lower housing, and the exhaust holes are opposite to the explosion-proof valves on both sides of the battery cells. Exhaust passages are provided inside the side beams on the left and right sides of the lower housing, and a plurality of exhaust holes are communicated with the exhaust passages. A cavity communicated with the exhaust passage is provided inside the front or rear side beam of the lower housing, and an explosion-proof valve of the battery pack is installed by opening a hole on the outer side wall of the front or rear side beam of the lower housing.

[0010] Further technical solution: no exhaust holes are provided at the corresponding positions on the inner side wall of the front or rear side beam of the lower housing where the explosion-proof valve of the battery pack is installed.

[0011] Further technical solution: the area of each exhaust hole is 1 to 2 times the breathable area of the explosion-proof valve of the battery pack.

[0012] Further technical solution: a louver structure that can be unfolded inwardly is provided on the inner side surface of each exhaust hole, and the louver structure is used to guide the gas to flow in the discharge direction and prevent the gas from rebounding to adjacent battery cells.

[0013] Further technical solution: a protective cover is provided at the outlet of the explosion-proof valve of the battery pack.

[0014] Further technical solution: the distances between the explosion-proof valves of the battery cells on both sides of the battery cells and the left and right side beams of the lower housing are both 5 mm respectively.

[0015] Further technical solution: a plurality of non-communicating exhaust channels are provided in sequence from top to bottom inside the left and right side beams of the lower housing.

[0016] Further technical solution: one side of each exhaust channel is communicated with the cavity, and each exhaust channel is communicated with a plurality of exhaust holes evenly arranged horizontally in sequence.

[0017] Further technical solution: the distance between two adjacent exhaust holes in the horizontal direction is 50 to 100 mm, and the distance between two adjacent exhaust holes in the vertical direction is 10 to 20 mm.

[0018] In the second aspect, the present utility model provides a battery pack.

[0019] A battery pack adopts the lower housing of the battery pack with an exhaust channel as described in the first aspect.

[0020] Compared with the prior art, the present utility model has the following beneficial effects:

[0021] 1. The present utility model provides a lower housing of a battery pack with an exhaust channel and a battery pack. An explosion-proof valve is still installed on the lower housing of the battery pack to discharge the gas and foreign matters inside the battery pack. The difference is that no exhaust holes are provided inside the installation beam of the explosion-proof valve of the battery pack to prevent the foreign matters generated by thermal runaway from blocking the explosion-proof valve of the battery pack and affecting the normal opening and exhaust of the explosion-proof valve of the battery pack. Instead, exhaust channels communicating with the inner cavity of the installation beam are provided in the left and right side beams of the lower housing. The exhaust holes of the exhaust channels are directly opposite to the explosion-proof valves of the battery cells. When the battery cells are in thermal runaway, the gas generated can be quickly discharged through the exhaust channels of the side beams of the lower housing. Moreover, while realizing the rapid discharge of gas, the space between the battery cells and the side beams of the lower housing can be reduced, the weight of the lower housing can be reduced, the cost can be reduced, and the energy density can be increased.

[0022] 2. The battery pack lower housing and the battery pack with an exhaust passage proposed by the present utility model rationally design the exhaust passage in the battery pack lower housing, timely discharge the generated gas and foreign matters from the battery pack, reduce the risk of thermal runaway, and at the same time can control the cost, improve the energy density, and enhance the product competitiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The schematic diagrams of the accompanying drawings constituting a part of the present utility model are used to provide a further understanding of the present utility model. The schematic embodiments and descriptions thereof of the present utility model are used to explain the present utility model and do not constitute an improper limitation to the present utility model.

[0024] Figure 1 It is a schematic structural diagram of placing battery cells in the battery pack lower housing with an exhaust passage in the present utility model;

[0025] Figure 2 It is a vertical sectional view of the battery pack lower housing with battery cells placed therein in the present utility model;

[0026] Figure 3 It is a vertical sectional view of the battery pack lower housing with battery cells placed therein in the present utility model;

[0027] Figure 4 It is a front structural schematic diagram of the battery pack lower housing with an exhaust passage in the present utility model;

[0028] Figure 5 It is a back structural schematic diagram of the battery pack lower housing with an exhaust passage in the present utility model;

[0029] Figure 6 It is a schematic diagram of the exhaust holes on the two side beams on the inner side of the battery pack lower housing in the present utility model;

[0030] Figure 7 It is a schematic diagram of the battery cells placed inside the battery pack lower housing in the present utility model;

[0031] Figure 8 It is a schematic diagram of the battery pack explosion-proof valve provided on the battery pack lower housing in the present utility model.

[0032] Among them, 1. Side beam; 2. Battery cell; 3. Battery pack explosion-proof valve; 4. Battery cell explosion-proof valve; 5. Exhaust hole; 6. Exhaust passage; 7. Battery pack lower housing. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] It should be noted that the following detailed descriptions are all illustrative and are intended to provide further explanations for the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0035] Embodiment 1

[0036] The utility model discloses a battery pack lower housing with an exhaust channel, as Figure 1 shown, the battery pack lower housing 7 is composed of a bottom plate and side beams 1 vertically fixed around the bottom plate, and a plurality of battery cells 2 are sequentially and closely placed inside the lower housing. As Figure 4 shown, a plurality of exhaust holes 5 are sequentially and evenly arranged on the inner side walls of the side beams 1 on the left and right sides of the lower housing. Combining Figure 2 and Figure 7 shown, exhaust channels 6 are provided inside the side beams on the left and right sides of the lower housing, and a plurality of exhaust holes 5 are communicated with the exhaust channels 6, and the exhaust holes 5 are directly opposite to the battery cell explosion-proof valves 4 on both sides of the battery cells. In addition, a cavity communicated with the exhaust channel 6 is provided inside the front or rear side beam of the lower housing, and a battery pack explosion-proof valve 3 is installed by opening a hole on the outer side wall of the front or rear side beam of the lower housing. Moreover, as Figure 5 shown, no exhaust holes are provided at the corresponding positions on the inner side walls of the front or rear side beams of the lower housing where the battery pack explosion-proof valve 3 is installed.

[0037] Through the above settings, when high-temperature mixed combustible gas and foreign matters such as dust are generated due to thermal runaway of the battery cells, the gas and foreign matters are ejected through the battery cell explosion-proof valves, enter the exhaust holes directly opposite to the battery cell explosion-proof valves, and then enter the exhaust channels. The gas and foreign matters are quickly transported and discharged through the exhaust channels; the exhaust channels are communicated with the cavities, and the transportation distance is increased as much as possible, which is beneficial to reducing the temperature of the combustible gas and also beneficial to the attachment of foreign matters such as dust to the inner wall of the channels, reducing the blockage degree at the battery pack explosion-proof valves. Moreover, no exhaust holes are provided inside the installation beams of the battery pack explosion-proof valves (i.e., the front or rear side beams of the above-mentioned lower housing), which can prevent foreign matters generated by thermal runaway from blocking the battery pack explosion-proof valves and affecting the normal opening and exhaust of the battery pack explosion-proof valves. In addition, through the above design, the space between the battery cells and the side beams of the lower housing can be reduced, and the hollow design can reduce the weight of the lower housing, reduce costs, and improve the energy density.

[0038] Furthermore, as Figure 3As shown, the spacing between the battery explosion-proof valves 4 on both sides of the battery cell 2 and the left and right side beams of the lower shell is 5 mm respectively (the battery cells with a certain spacing can be fixed by setting long strip blocks on the bottom plate, or by other methods). Through this design, while ensuring rapid exhaust inside the battery pack, the space between the battery cell and the side beam of the lower shell can be reduced, thereby improving the energy density.

[0039] Furthermore, the area of ​​each exhaust hole 5 is 1 to 2 times the ventilation area of ​​the battery pack explosion-proof valve 3. Specifically, the area of ​​the exhaust hole is set according to the specific situation. When the exhaust hole area is small, it will affect the final exhaust effect. Since the beam space is limited, the exhaust hole area is also affected by the beam space and will not be set very large. In this embodiment, it is set to 1 to 2 times the ventilation area of ​​the battery pack explosion-proof valve, and the exhaust effect is optimal.

[0040] As another embodiment, considering that after the explosion-proof valve of the battery cell ejects high-temperature gas and foreign matter, the gas enters the exhaust channel through the exhaust hole, and the gas flows along the exhaust channel. Usually, it does not flow out along other exhaust holes connected to the exhaust channel, but directly enters the cavity and is then discharged by the explosion-proof valve of the battery pack. Preferably, in this embodiment, a shutter structure that can be deployed inward is provided on the inner side of each exhaust hole to guide the gas to flow in the exhaust direction and prevent the gas from being discharged from other exhaust holes, thereby preventing the gas from rebounding to the adjacent battery cell.

[0041] Further, such as Figure 8 As shown, the battery pack explosion-proof valve 3 is arranged on the side away from the battery cell 2, and is used to discharge combustible gas and some foreign matter such as dust to the outside of the battery pack shell to prevent the battery pack from exploding; a protective cover is provided at the outlet of the battery pack explosion-proof valve to prevent the discharged combustible gas and dust from being directly sprayed onto external personnel, vehicles or structures to achieve the purpose of protection.

[0042] like Figure 2 As shown, multiple exhaust channels 6 that are not interconnected are sequentially arranged inside the side beams 1 on the left and right sides of the lower shell from top to bottom (three exhaust channels are arranged in upper, middle and lower in this embodiment). The provision of multiple exhaust channels is conducive to the rapid discharge of gas. At the same time, in order to ensure the structural strength of the cross beam, the multiple exhaust channels are not interconnected; one side of each exhaust channel is connected to the cavity, and each exhaust channel is connected to multiple exhaust holes that are uniformly arranged horizontally in sequence.

[0043] Further, such as Figure 6As shown, the distance between two adjacent exhaust holes 5 in the horizontal direction is 50 - 100 mm, the distance between two adjacent exhaust holes in the vertical direction is 10 - 20 mm, and the size of the exhaust hole is 100×15 mm. Further, the relevant parameters of the exhaust hole 5 can be adjusted according to specific situations. Through the design of the above exhaust channels and exhaust holes, the side beam can be lightened by 10%, effectively reducing costs.

[0044] Embodiment 2

[0045] The present utility model provides a battery pack, which adopts the battery pack lower housing with an exhaust channel as described in Embodiment 1.

[0046] For the battery pack lower housing with an exhaust channel and the battery pack proposed by the present utility model above, by reasonably designing the exhaust channel in the battery pack lower housing, the generated gas and foreign matters can be discharged from the battery pack in a timely manner, reducing the risk of thermal runaway. At the same time, the cost can be controlled, the energy density can be improved, and the product competitiveness can be enhanced.

[0047] Although the specific implementation manners of the present utility model are described above in conjunction with the drawings, it is not a limitation to the protection scope of the present utility model. Those skilled in the art should understand that based on the technical solutions of the present utility model, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present utility model.

Claims

1. A battery pack lower shell with an exhaust channel, characterized in that: It is composed of a bottom plate and side beams fixed vertically around the bottom plate, and multiple battery cells are closely placed inside the lower shell in sequence; A plurality of exhaust holes are evenly arranged on the inner walls of the left and right side beams of the lower shell, and the exhaust holes are directly opposite to the battery cell explosion-proof valves on both sides of the battery cell; an exhaust channel is arranged inside the left and right side beams of the lower shell, and a plurality of exhaust holes are connected to the exhaust channel; a cavity connected to the exhaust channel is arranged inside the front or rear side beam of the lower shell, and a hole is opened on the outer wall of the front or rear side beam of the lower shell to install the battery pack explosion-proof valve.

2. The battery pack lower housing with an exhaust channel according to claim 1, characterized in that: No exhaust hole is provided on the inner wall of the front or rear side beam of the lower shell at a position corresponding to the installation position of the battery pack explosion-proof valve.

3. The battery pack lower housing with an exhaust channel according to claim 1, characterized in that: The area of ​​each exhaust hole is 1 to 2 times the ventilation area of ​​the battery pack explosion-proof valve.

4. The battery pack lower housing with an exhaust channel according to claim 1, characterized in that: The inner side surface of each exhaust hole is provided with a shutter structure that can be movably expanded inwards, and the shutter structure is used to guide the gas to flow in the exhaust direction and prevent the gas from rebounding to the adjacent battery core.

5. The battery pack lower housing with an exhaust channel according to claim 1, characterized in that: A protective cover is provided at the outlet of the battery pack explosion-proof valve.

6. The battery pack lower housing with an exhaust channel according to claim 1, characterized in that: The distances between the battery cell explosion-proof valves on both sides of the battery cell and the left and right side beams of the lower shell are 5mm respectively.

7. The battery pack lower housing with an exhaust channel according to claim 1, characterized in that: A plurality of mutually unconnected exhaust passages are arranged in sequence from top to bottom inside the side beams on the left and right sides of the lower shell.

8. The battery pack lower housing with an exhaust channel according to claim 7, characterized in that: One side of each exhaust channel is communicated with the mold cavity, and each exhaust channel is communicated with a plurality of exhaust holes which are uniformly arranged in sequence horizontally.

9. The battery pack lower housing with an exhaust channel according to claim 8, characterized in that: The spacing between two exhaust holes in the horizontal direction is 50 to 100 mm, and the spacing between two exhaust holes in the vertical direction is 10 to 20 mm.

10. A battery pack, characterized in that: A battery pack lower shell with an exhaust channel as described in any one of claims 1 to 9 is used.

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