Shell with anti-explosion valve and battery cell

Abstract

The utility model relates to the technical field of battery cells, and discloses a shell with an anti-explosion valve and a battery cell, the shell comprises the shell and the anti-explosion valve, the side surface of the shell is stamped from inside to outside to form at least one boss structure, a groove is correspondingly formed in the shell, a reinforcing rib is formed in the middle of the boss structure, and blast holes are formed in the two sides of the reinforcing rib; the explosion-proof valve comprises a rupture disk, the rupture disk is correspondingly installed at the position of the groove, the thickness of the rupture disk is smaller than the depth of the groove, the rupture disk is provided with a nick connecting part, the nick connecting part is correspondingly arranged at the position of the inner side face of the reinforcing rib, and the rupture disk at the position of the blast hole is provided with a nick; the boss structure and the reinforcing rib structure are cooperatively arranged, on one hand, space is provided for installation of the anti-explosion valve, on the other hand, the strength of the position, where the anti-explosion valve is located, of the shell is enhanced, and deformation of the position is reduced; and the boss structure protrudes towards the outer side of the shell, so that the explosion-proof valve does not occupy the internal space of the battery cell, the thickness of the shell does not need to be increased, and the energy density of the battery cell is not influenced by opening the explosion-proof valve on the side surface.

Description

Technical Field

[0001] The utility model relates to the technical field of battery cells, in particular to a housing and a battery cell provided with an explosion-proof valve. Background Art

[0002] With the rapid development of new energy technologies, power batteries are increasingly widely used. With the concepts of extreme performance, extreme safety, and extreme cost put forward, the extreme safety performance of battery cells is closely related to the safety of the entire vehicle and consumers. The pressure relief rate and pressure relief direction of the pressure relief mechanism of battery cells are crucial for the safety performance of battery cells. Currently, most of the explosion-proof valve structures of battery cells are arranged on the cover plate of the battery cell, in the same direction as the positive and negative electrode posts. When the explosion-proof valve is opened, a large amount of high-temperature, high-humidity, and highly corrosive gas, liquid, or solid material sprays out from the explosion-proof valve, which easily contacts the positive and negative electrode posts of adjacent battery cells or modules, triggering further short circuits, and thus the entire battery pack is more likely to get out of control.

[0003] Based on the problems existing in the arrangement of the explosion-proof valve on the cover plate of the battery cell, the design of the explosion-proof valve has also started to shift from the cover plate to the side or bottom of the housing. However, the wall thickness of the side of the housing where the explosion-proof valve is arranged will increase accordingly, which increases the weight of the housing and also reduces the internal space of the battery cell, greatly reducing the energy density of the battery cell. Without increasing the wall thickness of the housing, the strength of the housing at the position of the explosion-proof valve is unstable, which has an adverse effect on the opening pressure of the explosion-proof valve and the stability of the explosion-proof valve, resulting in a reduction in the safety performance of the battery cell. Summary of the Utility Model

[0004] Aiming at the deficiencies of the prior art, the purpose of the utility model is to provide a housing battery cell provided with an explosion-proof valve. By corresponding design of the housing structure and the explosion-proof valve structure, the housing can ensure the housing strength without thickening and without occupying the internal space of the housing due to the installation of the explosion-proof valve.

[0005] In order to achieve the above purpose, the utility model is realized by the following technical solutions:

[0006] A housing provided with an explosion-proof valve includes a housing and an explosion-proof valve. At least one convex structure is formed by stamping from the inside to the outside on the side of the housing, and a groove is correspondingly formed inside the housing. A reinforcing rib is formed at the middle position of the convex structure, and blasting holes are formed on both sides of the reinforcing rib; the explosion-proof valve includes a bursting disc, the bursting disc is correspondingly installed at the groove, the thickness of the bursting disc is less than the depth of the groove, a scoring connecting part is arranged on the bursting disc, the scoring connecting part is correspondingly arranged at the inner side of the reinforcing rib, and a score is arranged on the bursting disc at the blasting hole.

[0007] As a further implementation method, the shape of the convex structure is adapted to the shape of the bursting disc.

[0008] As a further implementation, the reinforcing rib is perpendicular to the length direction of the boss structure, and the reinforcing rib is arranged parallel to the notch connecting part.

[0009] As a further implementation, the width of the reinforcing rib is smaller than the width of the notch connecting part.

[0010] As a further implementation, the edge of the rupture disk is set as a welding area, and the rupture disk is welded at the groove through the welding area.

[0011] As a further implementation, the inner side of the welding area is a thinning area, the thickness of the thinning area is smaller than the thickness of the welding area, and notches and notch connecting parts are arranged at the thinning area.

[0012] As a further implementation, the notch includes a first notch and a second notch arranged on both sides of the notch connecting part, the first notch and the second notch are oppositely arranged and are in a U shape, and both the first notch and the second notch are exposed at the rupture hole.

[0013] As a further implementation, the distance from the first notch and the second notch to the reinforcing rib is greater than or equal to 2 mm.

[0014] As a further implementation, the housing is formed by welding after roll bending or bending, and the explosion-proof valve is arranged on the side of the housing on the non-weld side.

[0015] In a second aspect, a battery cell includes a housing, one end of the housing is welded with a positive cover plate assembly, the other end is welded with a negative cover plate assembly, and the housing adopts the housing provided with an explosion-proof valve as described in any one of the above.

[0016] The beneficial effects of the above-mentioned present invention are as follows:

[0017] 1. In the present invention, a boss structure, a reinforcing rib and a rupture hole are formed on the side surface of the housing by stamping, and a groove for installing an explosion-proof valve is correspondingly formed on the inner side of the housing. The boss structure and the reinforcing rib structure are cooperatively arranged. On the one hand, it provides space for the installation of the explosion-proof valve, and on the other hand, it strengthens the strength of the position of the explosion-proof valve on the housing, reducing the deformation of this position; and because the boss structure protrudes outward from the housing, installing the explosion-proof valve does not occupy the internal space of the battery cell, nor is it necessary to increase the thickness of the housing, and the energy density of the battery cell is not affected by opening the explosion-proof valve on the side; through the special design of the structure and the opening position of the rupture disk, it can be ensured that the reinforcing rib does not affect the opening of the explosion-proof valve.

[0018] 2. The reinforcing rib of the present invention is located outside the rupture disk, a notch connecting part is correspondingly arranged on the rupture disk, and the first notch and the second notch are located on both sides of the notch connecting part, so that when the rupture disk is opened, the first opening area and the second opening area are opened from the rupture holes on both sides of the reinforcing rib. Brief Description of the Drawings

[0019] The accompanying drawings forming 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.

[0020] Figure 1 It is a schematic diagram of the overall structure of the battery cell in an embodiment of the present utility model;

[0021] Figure 2 It is a schematic diagram of the position of the explosion-proof valve of the battery cell in an embodiment of the present utility model;

[0022] Figure 3 It is a schematic diagram of the structure of the battery cell housing in an embodiment of the present utility model;

[0023] Figure 4 It is a cross-sectional view of the battery cell housing in an embodiment of the present utility model;

[0024] Figure 5 It is a schematic diagram of the overall structure of the rupture disk in an embodiment of the present utility model.

[0025] In the figure: The distances or sizes between each part are exaggerated for showing the positions of each part, and the schematic diagram is only for illustration.

[0026] Among them: 1. Battery cell, 10. Housing, 20. Explosion-proof valve;

[0027] 101. Side of the housing, 102. Boss structure, 103. Reinforcing rib, 104. Blasting hole, 201. Rupture disk;

[0028] 2011. Second notch, 2012. First notch, 2013. Notch connection part, 2014. First opening area, 2015. Second opening area, 2016. Welding area, 2017. Thinning area. Detailed implementation manners

[0029] It should be noted that the following detailed descriptions are all exemplary and are intended to provide a further description of the present utility model. Unless otherwise specified, all technical and scientific terms used in the present utility model have the same meanings as those commonly understood by those of ordinary skill in the technical field to which the present utility model belongs.

[0030] Embodiment 1

[0031] In a typical implementation manner of the present utility model, refer to Figures 1-5As shown in the figure, a housing provided with an explosion-proof valve includes a housing 10 and an explosion-proof valve 20. A boss structure 102 is formed by stamping the side surface 101 of the housing from the inside outwards, and a groove is correspondingly formed inside the housing. A reinforcing rib 103 is formed at the middle position on the boss structure 102, and blasting holes 104 are formed on both sides of the reinforcing rib. The explosion-proof valve 20 includes a bursting disc 201, and the bursting disc 201 is correspondingly installed at the groove. A scoring connection part is provided on the bursting disc 201, and the scoring connection part 2013 is correspondingly arranged at the inner side surface of the reinforcing rib. A score is provided on the bursting disc 201 at the blasting hole 104.

[0032] In this embodiment, the outer shape of the bursting disc 201 is oblong, and its shape is adapted to the shape of the boss structure 102. The bursting disc and the boss structure both extend along the length direction of the housing.

[0033] The explosion-proof valve is located on one side of the housing. One or more explosion-proof valves 20 can be provided, and the bursting disc 201 of each explosion-proof valve is correspondingly arranged with a group of boss structures 102.

[0034] The bursting disc 201 is fixedly connected to the inner groove of the housing by welding. The cell housing is made of aluminum or steel, and can be formed by roll bending or bending and then welding. The housing 10 is a structure with both ends open. One end is welded with a positive cover assembly, and the other end is welded with a negative cover assembly. The housing 10 has a total of four surfaces, two large surfaces and two side surfaces. Among them, the explosion-proof valve 20 is arranged on the boss structure 102 of the side surface on the non-weld side. The wall thickness of the housing 10 is usually between 0.2 mm and 0.5 mm, and the wall thicknesses of the four surfaces are the same and uniform.

[0035] Considering that setting the explosion-proof valve on the side surface 101 of the housing will cause the wall thickness of the side surface 101 of the housing to increase correspondingly, which increases the weight of the housing and also reduces the internal space of the cell 1. In this embodiment, a boss structure is provided to realize the reasonable installation of the explosion-proof valve without changing the inner space of the housing.

[0036] In order to install the bursting disc 201 on the side surface 101 of the housing, it is necessary to set the blasting hole 104, and the blasting hole 104 is formed by stamping the side surface 101 of the housing from the inside outwards. As Figure 3 and Figure 4 shown, through stamping, a groove is formed inside the housing, and correspondingly, a boss structure 102 is formed outside the housing 10. The reinforcing rib 103 is formed while stamping the blasting hole.

[0037] As Figure 2 and Figure 3 shown, the reinforcing rib 103 is formed by stamping the housing. The reinforcing rib 103 is perpendicular to the length direction of the boss structure 102. The reinforcing rib 103 is located at the middle position of the boss structure, and the areas of the blasting holes on both sides of it are the same.

[0038] In this embodiment, the boss structure 102, also known as the bulging structure, is cooperatively arranged with the reinforcing rib 103. On the one hand, the formed groove provides an installation space for installing the rupture disk 201, and the thickness of the rupture disk is less than the depth of the groove. After installing the rupture disk 201, the volume inside the shell will not be significantly reduced. On the other hand, the reinforcing rib 103 improves the strength of the position of the explosion-proof valve of the shell, reduces the deformation at this position, and increases the stability of the explosion-proof valve 20.

[0039] As Figure 5 shown, the rupture disk 201 is the explosion-proof valve 20 of this embodiment and is used to be installed at the groove formed by stamping the shell 10. The edge of the rupture disk 201 is set as the welding area 2016, which is thicker at this position and is used for welding with the shell. When installing the rupture disk, the rupture disk 201 is placed at the groove, and the welding area 2016 abuts against the groove, and the rupture disk is fixed at the groove by laser welding.

[0040] The inner side of the welding area is the thinning area 2017, and the thickness of the thinning area 2017 is less than the thickness of the welding area. The thinning area 2017 can buffer the influence of the welding process on the notch.

[0041] The thinning area 2017 is provided with notches and notch connection parts. The notch connection part 2013 is formed at the middle position of the thinning area 2017. Since the thickness of the thinning area 2017 is less than the thickness of the welding area, the reinforcing rib is arranged parallel to the notch connection part, but they do not contact.

[0042] Notches are correspondingly arranged on the thinning areas 2017 on both sides of the notch connection part 2013. The notches include the first notch 2012 and the second notch 2011. The first notch 2012 and the second notch 2011 are oppositely arranged and are in a U shape, and the openings of the two notches are opposite. The first notch 2012 and the second notch 2011 are both exposed at the explosion hole.

[0043] When the internal pressure of the battery cell 1 reaches the threshold value, by setting the first notch 2012 and the second notch 2011, the pressure can be relieved in time to prevent the battery cell from exploding due to excessive internal pressure that cannot be discharged. The first opening area 2014 is formed at the first notch 2012, and the second opening area 2015 is formed at the second notch 2011. The two opening areas are the opening area of the rupture disk 201, and the size of the opening area is positively correlated with the capacity of the battery cell. When opening, the first opening area 2014 and the second opening area 2015 are opened from the explosion hole.

[0044] After the rupture disk 201 is installed on the groove, the notch connecting part 2013 is correspondingly located inside the reinforcing rib. The setting of the notch connecting part ensures that on the one hand, when the rupture disk 201 is opened, it will not bounce off entirely, causing damage to other components of the battery cell or injury to people. On the other hand, because the outer side of the notch connecting part 2013 is the reinforcing rib 103 of the housing, this position cannot be set as a notch. Because if a notch is set in this area, it will not be able to open normally. In order to enable the rupture disk to open smoothly, the width of the reinforcing rib 103 should be less than the width of the notch connecting part.

[0045] As Figure 2 shown, L1 represents the distance between the notch and the reinforcing rib 103; L2 represents the distance between the notch in the length direction and the edge of the housing; L3 represents the distance between the notch in the width direction and the edge of the housing. L1, L2, and L3 are respectively the distances from the notch to the periphery, and all three distances should be greater than or equal to 2 mm to ensure that the explosion-proof valve can open normally and will not be blocked by the housing or the reinforcing rib.

[0046] Thus, on the one hand, the design of the housing boss structure 102 combined with the reinforcing rib 103 improves the strength of the housing, reduces the welding stress of the rupture disk, protects the rupture disk, and improves the reliability and safety performance of the explosion-proof valve; on the other hand, the special design of the rupture disk notch and its cooperation with the housing ultimately ensure the normal opening and pressure relief of the explosion-proof valve and the safety of the battery cell; on the third hand, by arranging the explosion-proof valve on the side of the housing, away from the pole column, thermoelectric separation is achieved, improving the ultimate safety performance of the battery cell.

[0047] Embodiment 2

[0048] In a typical implementation manner of the present utility model, referring to Figures 1-5 shown, a battery cell, the battery cell 1 includes a housing 10, and the material of the housing 10 is not limited and can be a steel shell or an aluminum shell. The housing is a two-end-through structure. One end of the housing is welded with a positive cover plate assembly, and the other end is welded with a negative cover plate assembly. The cover plate assembly is a prior art. The housing adopts the housing with an explosion-proof valve in Embodiment 1. One or more explosion-proof valves 20 can be installed on the side 101 of the housing. Each rupture disk corresponds to a set of boss structures.

[0049] Since the housing is relatively thin, there is a risk of deformation during welding and use, resulting in unstable opening pressure of the rupture disk or cracks in the rupture disk. Therefore, the strength of the housing is strengthened for the first time through the boss structure, and at the same time, the boss structure can relieve the stress during the welding process of the rupture disk, thereby further ensuring the stability of the rupture disk. In addition, the setting of the reinforcing rib 103 strengthens the strength of the housing for the second time. Therefore, through the combination of the bulge structure and the reinforcing rib structure, the strength of the housing is ensured, thereby ensuring the stability of the rupture disk.

[0050] The above are only the preferred embodiments of the present utility model and are not intended to limit the present utility model. For those skilled in the art, various modifications and variations can be made to the present utility model. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A housing provided with an explosion-proof valve, characterized in that: The explosion-proof valve (20) comprises a shell (10) and an explosion-proof valve (20). The shell (10) is punched from the inside to the outside to form at least one boss structure (102). A groove is correspondingly formed inside the shell (10). A reinforcing rib (103) is formed in the middle of the boss structure (102). A blasting hole (104) is formed on both sides of the reinforcing rib (103). The explosion-proof valve (20) comprises a bursting disc (201). The bursting disc (201) is correspondingly installed at the groove. The thickness of the bursting disc (201) is less than the depth of the groove. A notched connecting portion (2013) is provided on the bursting disc (201). The notched connecting portion (2013) is correspondingly arranged at the inner side of the reinforcing rib (103). The bursting disc (201) at the blasting hole (104) is notched.

2. A housing with an explosion-proof valve according to claim 1, characterized in that: The shape of the boss structure (102) is adapted to the shape of the bursting disc (201).

3. A housing with an explosion-proof valve according to claim 1, characterized in that: The reinforcing rib (103) is perpendicular to the length direction of the boss structure (102), and the reinforcing rib (103) is arranged in parallel with the notched connection portion (2013).

4. A housing with an explosion-proof valve according to claim 3, characterized in that: The width of the reinforcing rib (103) is smaller than the width of the notched connecting portion (2013).

5. The housing provided with an explosion-proof valve according to claim 1, characterized in that: The edge of the bursting piece (201) is set as a welding area (2016), and the bursting piece (201) is welded to the groove through the welding area (2016).

6. A housing with an explosion-proof valve according to claim 5, characterized in that: The inner side of the welding zone (2016) is a thinning zone (2017), the thickness of the thinning zone (2017) is less than the thickness of the welding zone (2016), and a notch and a notch connecting portion (2013) are provided at the thinning zone (2017).

7. A housing with an explosion-proof valve according to claim 6, characterized in that: The notches include a first notch (2012) and a second notch (2011) disposed on both sides of the notch connection portion; the first notch (2012) and the second notch (2011) are disposed opposite to each other and are U-shaped; the first notch (2012) and the second notch (2011) are both exposed at the blasting hole (104).

8. The housing provided with an explosion-proof valve according to claim 7, characterized in that: The distances from the first notch (2012) and the second notch (2011) to the reinforcing rib (103) are greater than or equal to 2 mm.

9. The housing provided with an explosion-proof valve according to claim 1, characterized in that: The shell (10) is formed by roll bending or bending followed by welding, and the explosion-proof valve (20) is arranged on the side surface of the shell (10) on the non-weld side.

10. A battery cell, characterized in that: The battery cell (1) comprises a shell (10), one end of the shell (10) is welded with a positive electrode cover plate assembly, and the other end is welded with a negative electrode cover plate assembly, and the shell (10) is a shell provided with an explosion-proof valve as described in any one of claims 1 to 9.

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