Shell assembly, battery and battery pack

Abstract

The utility model provides a shell assembly, a battery and a battery pack. The shell assembly comprises a shell and a cover plate assembly, the shell is used for containing the battery cell assembly, the cover plate assembly is connected with one end of the shell, the cover plate assembly comprises a first protruding part protruding in the direction away from the shell and a sunken part sunken in the direction close to the shell, and the sunken part is used for abutting against the battery cell assembly. The first convex part, the concave part and the shell are used for enclosing with the battery cell assembly to form a first air chamber. The first gas chamber is formed in the shell assembly, so that the first gas chamber can store the gas generated by the battery cell assembly in the shell when the shell assembly is put into use, the gas storage capacity of the shell assembly is improved, the safety of the shell assembly is improved, and the service life of the shell assembly is prolonged.

Description

Technical Field

[0001] This application relates to the field of battery technology, specifically to a housing assembly, a battery, and a battery pack. Background Technology

[0002] With the development of battery technology, the requirements for battery safety and lifespan are becoming increasingly stringent. A major cause of battery safety issues lies in the large amount of gas generated during battery use. This gas is stored in the battery casing, and when a certain pressure is reached, it can breach the casing, leading to battery failure. However, the space available for gas storage in the casing is limited in current technologies, resulting in a limited gas storage capacity and consequently, relatively poor safety for the casing. Utility Model Content

[0003] Embodiments of this application provide a housing assembly, a battery, and a battery pack, which can improve the problem of poor safety performance of the housing assembly.

[0004] In a first aspect, embodiments of this application provide a housing assembly, including:

[0005] The housing is used to hold the battery cell assembly;

[0006] A cover plate assembly is connected to one end of the housing; the cover plate assembly includes a first protrusion protruding away from the housing and a recessed portion recessed towards the housing, the recessed portion being used to abut against the cell assembly; the first protrusion, the recessed portion, and the housing are used to enclose the cell assembly to form a first air chamber.

[0007] In one embodiment, the first protrusion and the recess are annular, and the recess is located within the area enclosed by the first protrusion.

[0008] In one embodiment, a pressure relief groove is provided on the first protrusion.

[0009] In one embodiment, the pressure relief groove extends circumferentially along the first protrusion in an annular shape, and the width of the bottom of the pressure relief groove is greater than or equal to 0.02 mm and less than or equal to 0.8 mm.

[0010] In one embodiment, the angle β formed by the sidewall of the pressure relief groove and the bottom of the pressure relief groove satisfies the following relationship: 95°≤β≤165°.

[0011] In one embodiment, the cover assembly further includes a second protrusion that protrudes away from the housing, the second protrusion being located within the area enclosed by the recess; the second protrusion and the recess are used to enclose and form a second air chamber with the cell assembly.

[0012] In one embodiment, the second protrusion has a through hole that extends through the second protrusion along its thickness direction.

[0013] In one embodiment, the height of the second protrusion is less than the height of the first protrusion; the difference between the heights of the second protrusion and the first protrusion is greater than or equal to 0.3 mm and less than or equal to 1 mm.

[0014] In one embodiment, the diameter P1 of the through hole and the diameter P2 of the second protrusion satisfy the relationship: 1mm < P1 < 0.8P2.

[0015] In one embodiment, in the protrusion direction along the second protrusion, at least part of the sidewall of the through hole is inclined away from the axis of the through hole, with an inclination angle α ≤ 70°.

[0016] In one embodiment, the housing assembly further includes a seal that connects to the second protrusion and seals the through-hole; the seal includes a transition portion recessed toward the housing and extending into the through-hole.

[0017] In one embodiment, the diameter P3 of the transition portion and the diameter P1 of the through hole satisfy the relationship: 0.2P1≤P3≤P1.

[0018] Secondly, embodiments of this application provide a battery, comprising:

[0019] The housing assembly described in any of the preceding claims; and...

[0020] The battery cell assembly is located inside the housing of the housing assembly;

[0021] A terminal assembly is connected to one end of the housing away from the cover plate assembly in the housing assembly.

[0022] Thirdly, embodiments of this application provide a battery pack including the aforementioned battery.

[0023] The beneficial effects of the embodiments of this application are as follows:

[0024] In embodiments of this application, the housing assembly includes a housing and a cover assembly. The housing is used to house the battery cell assembly, and the cover assembly is connected to one end of the housing. The cover assembly includes a first protrusion protruding away from the housing and a recessed portion recessed towards the housing. The recessed portion is used to abut against the battery cell assembly. The first protrusion, the recessed portion, and the housing are used to enclose the battery cell assembly to form a first air chamber. By forming a first air chamber within the housing assembly, this application enables the housing assembly to store the gas generated by the battery cell assembly during use, thereby improving the gas storage capacity of the housing assembly and thus contributing to improved safety performance and service life. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of a housing assembly provided in an embodiment of this application;

[0027] Figure 2 This is a schematic diagram of the structure of a cover plate assembly provided in an embodiment of this application;

[0028] Figure 3 This is a schematic diagram of a pressure relief groove provided in an embodiment of this application;

[0029] Figure 4 This is a schematic diagram of different types of through holes provided on a second protrusion according to an embodiment of this application;

[0030] Figure 5 This is a schematic diagram of the mating structure of a seal and a second protrusion provided in an embodiment of this application;

[0031] Figure 6 This is a schematic diagram of the structure of a battery provided in an embodiment of this application.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Battery;

[0034] 10, housing assembly; 11, housing; 113, opening; 12, cover assembly; 121, pressure relief groove; 123, first protrusion; 124, recess; 125, second protrusion; 1251, through hole; 126, seal; 1261, transition; 14, first air chamber; 15, second air chamber;

[0035] 20. Terminal assembly;

[0036] 30, Battery cell assembly; 31, Positive current collector; 32, Negative current collector; 33, Core. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0038] First, this application provides a housing assembly, such as... Figure 1 As shown, the housing assembly 10 includes a housing 11, which has a receiving cavity for placing the battery cell assembly 30. One end of the housing 11 has an opening 113 to facilitate the insertion and assembly of the battery cell assembly 30.

[0039] The housing assembly 10 includes a cover assembly 12, which is connected to the housing 11 and seals the opening 113 to achieve sealed protection of the cell assembly 30 inside the housing 11, preventing the cell assembly 30 from being corroded by the external environment, thereby ensuring the performance of the battery 1.

[0040] The cover assembly 12 includes a first protrusion 123 protruding away from the housing 11 and a recess 124 recessed towards the housing 11. The recess 124 abuts against the cell assembly 30. The first protrusion 123, the recess 124, and the housing 11 together enclose the cell assembly 30 to form a first air chamber 14. When the cover assembly 12 is assembled with the housing 11, the recess 124 on the cover assembly 12 directly abuts against the cell assembly 30 to achieve a live design for the cover assembly 12. The first protrusion 123, the recess 124, the housing 11, and the cell assembly 30 together enclose the first air chamber 14, which stores the gas generated during the operation of the battery 1. In other words, the first air chamber 14 effectively improves the gas storage capacity of the housing assembly 10, thereby improving the safety performance and service life of the housing assembly 10, and consequently, the safety and service life of the battery 1.

[0041] In the embodiments of this application, the housing assembly 10 includes a housing 11 and a cover assembly 12. The housing 11 is used to house the battery cell assembly 30. The cover assembly 12 is connected to one end of the housing 11. The cover assembly 12 includes a first protrusion 123 protruding away from the housing 11 and a recess 124 recessed towards the housing 11. The recess 124 is used to abut against the battery cell assembly 30. The first protrusion 123, the recess 124, and the housing 11 are used to enclose the battery cell assembly 30 to form a first air chamber 14. By forming a first air chamber 14 in the housing assembly 10, this application enables the first air chamber 14 to store the gas generated by the battery cell assembly 30 inside the housing 11 during use, thereby improving the gas storage capacity of the housing assembly 10 and thus helping to improve the safety performance and service life of the housing assembly 10.

[0042] Optional, such as Figure 1 As shown, the first protrusion 123 and the recess 124 are annular, and the recess 124 is located within the area enclosed by the first protrusion 123, meaning that the first air chamber 14 is also annular. By setting the first air chamber 14 as annular, the gas stored in the first air chamber 14 is more evenly distributed within the housing assembly 10, thereby making the stress on the cover assembly 12 more even, which helps to improve the stability of the housing assembly 10 during use.

[0043] The width of the recess 124 (the difference between the outer diameter and the inner diameter) is greater than or equal to 4 mm and less than or equal to 8 mm. If the width of the recess 124 is too small, the area of ​​the recess 124 that is used to abut against the battery cell assembly 30 will be too small, which is not conducive to the live design of the cover plate assembly 12. If the width of the recess 124 is too large, the air chamber space inside the housing assembly 10 will be reduced, thereby affecting the gas storage capacity of the housing assembly 10.

[0044] In the actual manufacturing process, the width of the recess 124 can be set to 4mm, 5mm, 6mm, 7mm or 8mm, etc. The specific width value can be adjusted according to the actual design requirements, and there are no special restrictions here.

[0045] In addition, such as Figure 2 As shown, in this embodiment, the height difference P4 between the side of the first protrusion 123 facing away from the housing 11 and the side of the recess 124 facing away from the housing 11 is set to 0.5mm≤P4≤2mm. If the height difference is too small, the space of the first gas chamber 14 will be small, which is not conducive to gas storage; if the height difference is too large, the space utilization rate inside the housing assembly 10 will be low, resulting in a low energy density of the battery 1.

[0046] In the actual production process, the height difference P4 can be set to 0.5mm, 1mm, 1.5mm or 2mm, etc. The specific value can be selected and adjusted according to the actual design requirements, and there are no special restrictions here.

[0047] In some embodiments, such as Figure 1 and Figure 3 As shown, a pressure relief groove 121 is provided on the first protrusion 123. When the first protrusion 123 is arranged in a ring, the pressure relief groove 121 extends in a ring along the circumference of the first protrusion. Since a first air chamber 14 is formed below the first protrusion 123, by providing the pressure relief groove 121 on the first protrusion 123, when the gas pressure stored in the first air chamber 14 is large, it can be relieved in time through the pressure relief groove 121, thereby helping to reduce the risk of explosion of the housing assembly 10 during use.

[0048] The bottom of the pressure relief groove 121 is the part that is forced open during pressure relief. To ensure that the pressure relief groove 121 has a sufficient pressure relief area, the width of the bottom of the pressure relief groove 121 can be set to be greater than or equal to 0.02 mm and less than or equal to 0.8 mm. If the width of the bottom of the pressure relief groove 121 is too small, the pressure relief area will be too small, and the pressure required for the gas to force open the pressure relief groove 121 will be too large, thereby increasing the risk of explosion. If the width of the bottom of the pressure relief groove 121 is too large, the area of ​​the weak area on the cover plate assembly 12 will be too large, which will cause the cover plate assembly 12 to be unable to withstand sufficient gas pressure, thereby reducing the overall safety performance and service life of the housing assembly 10.

[0049] In the actual manufacturing process, the width of the bottom of the pressure relief groove 121 can be set to 0.02mm, 0.05mm, 0.1mm, 0.3mm, 0.5mm or 0.8mm, etc. The specific width value can be selected and adjusted according to the actual design requirements, and there are no special restrictions here.

[0050] In other embodiments, such as Figure 3 As shown, the angle β formed by the sidewall and bottom of the pressure relief groove 121 satisfies the relationship: 95°≤β≤165°, that is, the sidewall of the pressure relief groove 121 tends to expand so that the pressure relief groove 121 can be pulled open when pressure is released. If the angle is too large, the stamping area will be too large, making molding difficult, and the strength of the cover assembly 12 will be reduced, making it unable to withstand sufficient gas pressure, thereby reducing the overall safety performance and service life of the housing assembly 10. If the angle is too small, the pressure required for the gas to break through the pressure relief groove 121 will be too large, thereby increasing the risk of explosion. At the same time, a small angle will cause the pressure relief groove 121 to deform during the battery manufacturing process, thereby reducing safety.

[0051] In the actual production process, the included angle can be set to 95°, 110°, 125°, 150° or 165°, etc. The specific angle value can be selected and adjusted according to the actual design requirements, and there are no special restrictions here.

[0052] Optional, such as Figure 1 As shown, the cover assembly 12 also includes a second protrusion 125 protruding away from the housing 11. The second protrusion 125 is located within the area enclosed by the recess 124. The second protrusion 125 and the recess 124 are used to enclose the cell assembly 30 to form a second air chamber 15. That is, the second air chamber 15 is located near the middle area of ​​the housing assembly 10, and the second air chamber 15 is also arranged in a ring shape. By forming the second air chamber 15 within the housing assembly 10, the gas storage capacity of the housing assembly 10 can be further and effectively improved, thereby helping to improve the safety performance and service life of the housing assembly 10, and thus improving the service life of the battery 1.

[0053] Among them, such as Figure 2 As shown, the second protrusion 125 has a through hole 1251, which extends through the second protrusion 125 along its thickness direction. The through hole 1251 can serve as an injection hole to facilitate the injection of liquid during the battery manufacturing process; or, the through hole 1251 can also serve as a vent hole to facilitate the discharge of gas generated during the battery formation process, thereby helping to improve the storage capacity of the battery 1 for the generated gas during use, and thus improving the safety of the battery 1 during use.

[0054] In some embodiments, the protrusion height of the second protrusion 125 is less than the protrusion height of the first protrusion 123, that is, the second protrusion 125 is recessed relative to the first protrusion 123. This is because the second protrusion 125 has a through hole 1251, which will be sealed later. Recessing the second protrusion 125 can prevent the height of the corresponding position after the through hole 1251 is sealed from being higher than the height of the first protrusion, thereby affecting the overall height of the housing assembly 10 and the flatness of the surface of the cover assembly 12.

[0055] The height difference between the second protrusion 125 and the first protrusion 123 is greater than or equal to 0.3 mm and less than or equal to 1 mm. If the height difference between the second protrusion 125 and the first protrusion 123 is too large, the second protrusion 125 will be too high, thus affecting the overall height of the housing assembly 10. Alternatively, the height of the first protrusion may be too small, which is not conducive to the formation of the air chamber. If the height difference between the second protrusion 125 and the first protrusion 123 is too small, the height of the sealing position will be higher than the height of the first protrusion 123 after the through hole 1251 on the second protrusion 125 is sealed, thus affecting the flatness of the surface of the cover assembly 12.

[0056] In the actual manufacturing process, the height difference between the second protrusion 125 and the first protrusion 123 can be set to 0.3mm, 0.5mm, 0.8mm or 1mm, etc. The specific difference can be selected and adjusted according to the actual design requirements, and no special restrictions are imposed here.

[0057] In other embodiments, such as Figure 2 As shown, the diameter P1 of the through hole 1251 on the second protrusion 125 and the diameter P2 of the second protrusion 125 satisfy the relationship: 1mm < P1 < 0.8P2. If the diameter of the through hole 1251 is too small, it will be difficult for the gas generated during the formation of the battery 1 to be discharged. If the diameter of the through hole 1251 is too large, it will affect the overall structural strength of the cover plate assembly 12 and increase the difficulty of sealing the through hole 1251.

[0058] In some other embodiments, such as Figure 4 As shown, in the protrusion direction along the second protrusion 125, at least part of the sidewall of the through hole 1251 is inclined away from the axis of the through hole 1251, with an inclination angle α ≤ 70°. That is, in the protrusion direction along the second protrusion 125, at least part of the sidewall of the through hole 1251 has an expanding tendency to facilitate the discharge of gas.

[0059] In the protrusion direction along the second protrusion 125, the through hole 1251 may include a straight cylindrical section and an inclined section that are interconnected. The inclination angle of the inclined section is α. The inclined section facilitates the subsequent sealing operation of the through hole 1251. Alternatively, in the protrusion direction along the second protrusion 125, the sidewall of the through hole 1251 is entirely inclined, that is, the through hole 1251 is an inclined hole with an inclination angle of α. The specific structure of the through hole 1251 can be selected and adjusted according to actual design requirements, and no special restrictions are imposed here.

[0060] Optional, such as Figure 5As shown, the housing assembly 10 also includes a seal 126, which connects to the second protrusion and seals the through hole 1251. The seal 126 includes a transition portion 1261 recessed towards the housing 11, which extends into the through hole 1251, meaning the seal 126 has an overall inverted V-shaped structure. Because the seal 126 itself is relatively thin, providing the transition portion 1261 on the seal 126 helps to place the seal 126 in the through hole 1251, facilitating welding to the second protrusion 125.

[0061] The diameter P3 of the transition portion 1261 and the diameter P1 of the through hole 1251 satisfy the relationship: 0.2P1≤P3≤P1. If the diameter of the transition portion 1261 is too large, the seal 126 may not be able to be assembled into the through hole 1251, thus making it impossible to weld and seal the through hole 1251. If the diameter of the transition portion 1261 is too small, the seal 126 may not be easy to put into the through hole 1251, thus affecting the efficiency and quality of the welding seal.

[0062] In the actual manufacturing process, the specific value of the diameter of the transition part 1261 can be designed and adjusted according to the diameter of the through hole 1251, and no special restrictions are imposed here.

[0063] It should be noted that since the seal 126 is installed in the through hole 1251 of the second protrusion 125, during installation, it is necessary to ensure that the lower surface of the transition section does not exceed the lower surface of the second protrusion 125 after assembly, so as to avoid the seal 126 interfering with the battery cell assembly 30 located in the housing 11.

[0064] In some embodiments, when the through hole 1251 is a straight cylindrical hole, the welding surface (side surface) of the seal 126 can be chamfered, and the chamfered welding surface forms an acute angle with the side of the seal 126 facing the through hole 1251 (e.g., Figure 5 As shown, this allows welding to be performed through the gap between the welding surface of the seal 126 and the sidewall of the through hole 1251 during sealing, thereby ensuring the sealing effect of the seal 126.

[0065] It should be noted that, in order to ensure the welding effect between the seal 126 and the sidewall of the through hole 1251, the width of the weld surface after chamfering in the radial direction of the through hole 1251 can be set to be greater than or equal to 0.2 mm, and its height in the axial direction of the through hole 1251 can be set to be greater than or equal to 0.2 mm. The specific width and height values ​​can be selected and adjusted according to actual design requirements, and no special restrictions are imposed here.

[0066] In other embodiments, when the through hole 1251 is composed of an inclined section and a straight section, the welding surface of the seal 126 can also be chamfered. In this case, the inclined direction of the welding surface after chamfering is consistent with the inclined direction of the inclined section of the through hole 1251, so that the welding surface of the seal 126 can fit against the side wall of the inclined section, thereby facilitating the welding of the seal 126 to the side wall of the through hole 1251.

[0067] Secondly, this application provides a battery, which includes a housing assembly. The specific structure of the housing assembly is as described in the above embodiments. Since this battery adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0068] like Figure 6 As shown, the battery 1 includes a housing assembly 10, a cell assembly 30, and a terminal assembly 20. The cell assembly 30 is located inside the housing 11 of the housing assembly 10. The terminal assembly 20 is connected to the end of the housing 11 away from the cover plate assembly 12 in the housing assembly 10, that is, the terminal assembly 20 and the cover plate assembly 12 are respectively connected to the two ends of the housing 11.

[0069] The battery cell assembly 30 includes a positive current collector 31, a negative current collector 32, and a core 33. The positive current collector 31 is electrically connected to the positive terminal of the core 33 and the terminal assembly 20. The negative current collector 32 is electrically connected to the negative terminal of the core 33 and the housing 11. The negative current collector 32 also abuts against the cover plate assembly 12. That is, the terminal assembly 20 is insulated from the housing 11. The terminal assembly 20 is the positive terminal of the battery 1, and the housing 11 is the negative terminal of the battery 1. By placing the terminal assembly 20 and the cover plate assembly 12 at both ends of the housing 11, and by providing a pressure relief groove 121 on the cover plate assembly 12, when the battery 1 experiences thermal runaway, only the cover plate assembly 12 will be damaged, without damaging the terminal assembly 20. Furthermore, the placement of the terminal assembly 20 will not affect the pressure relief of the pressure relief groove 121, thereby helping to improve the overall safety performance of the battery 1.

[0070] Specifically, such as Figure 1As shown, the housing assembly 10 includes a housing 11 and a cover assembly 12. The housing 11 is used to house the battery cell assembly 30. The cover assembly 12 is connected to one end of the housing 11. The cover assembly 12 includes a first protrusion 123 protruding away from the housing 11 and a recess 124 recessed towards the housing 11. The recess 124 abuts against the battery cell assembly 30. The first protrusion 123, the recess 124, and the housing 11 are used to enclose the battery cell assembly 30 to form a first air chamber 14. By forming a first air chamber 14 inside the housing assembly 10, this application enables the first air chamber 14 to store the gas generated by the battery cell assembly 30 inside the housing 11 during use, thereby improving the gas storage capacity of the housing assembly 10 and thus helping to improve the safety performance and service life of the housing assembly 10.

[0071] Finally, this application embodiment also provides a battery pack, which includes a battery. The specific structure of the battery is as described in the above embodiments. Since this battery pack adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be described in detail here.

[0072] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A housing assembly, characterized by, The shell is used for placing the battery cell assembly. The cover plate assembly is connected to one end of the shell, and includes a first protruding part protruding away from the shell and a recessed part recessed towards the shell, the recessed part being used for abutting the battery cell assembly; the first protruding part, the recessed part and the shell are used for enclosing the battery cell assembly to form a first gas chamber. The first protruding part and the recessed part are annular, and the recessed part is located in an area enclosed by the first protruding part.

2. The housing assembly of claim 1, wherein, The first protruding part is provided with a pressure relief groove.

3. The housing assembly of claim 1 or 2, wherein, The pressure relief groove is annular along the circumferential direction of the first protruding part, and the width of the bottom of the pressure relief groove is greater than or equal to 0.02 mm and less than or equal to 0.8 mm.

4. The housing assembly of claim 3, wherein, The included angle β between the side wall of the pressure relief groove and the bottom of the pressure relief groove satisfies the relationship: 95°≤β≤165°.

5. The housing assembly of claim 4, wherein, The cover plate assembly further includes a second protruding part protruding away from the shell, and the second protruding part is located in an area enclosed by the recessed part; the second protruding part and the recessed part are used for enclosing the battery cell assembly to form a second gas chamber.

6. The housing assembly of claim 2, wherein, The second protruding part is provided with a through hole penetrating the second protruding part along the thickness direction of the second protruding part.

7. The housing assembly of claim 6, wherein, The protruding height of the second protruding part is less than the protruding height of the first protruding part; the difference between the height of the second protruding part and the height of the first protruding part is greater than or equal to 0.3 mm and less than or equal to 1 mm.

8. The housing assembly of claim 7, wherein, The diameter P1 of the through hole and the diameter P2 of the second protruding part satisfy the relationship: 1 mm 9. The housing assembly of claim 7, wherein, In the protruding direction of the second protruding part, the side wall of the through hole is at least partially inclined away from the axis of the through hole, and the inclination angle α is less than or equal to 70°.

10. The housing assembly of claim 7, wherein, The shell assembly further includes a sealing member connected to the second protruding part and sealing the through hole; the sealing member includes a transition part recessed towards the shell, and the transition part extends into the through hole.

11. The housing assembly of claim 7, wherein, The diameter P3 of the transition part and the diameter P1 of the through hole satisfy the relationship: 0.2P1≤P3≤P1.

12. The housing assembly of claim 11, wherein, The shell assembly of any one of claims 1 to 12; 13. A battery, characterized by The battery cell assembly is located in the shell of the shell assembly; And The terminal assembly is connected to the end of the shell away from the cover plate assembly in the shell assembly. The battery of claim 13. ​ 14. A battery pack, characterized by ​

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