Cover plate assembly, battery and battery module

Abstract

Cover plate assembly comprising: A cover plate (200); An insulating piece (100) comprising a connecting section (1) and a guide section (2), wherein the connecting section (1) is attached to the cover plate (200); the guide section (2) is annular and is connected to a side of the connecting section (1) facing away from the cover plate (200) in a first direction, wherein the guide section (2) comprises a cavity (3), wherein the guide section (2) comprises a guide running surface (21) facing away from the cavity (3), wherein the guide running surface (21) is an inclined surface; wherein an orthogonal projection of the guide running surface (21) lies completely within the connecting section (1) in a first direction, the first direction being perpendicular to the cover plate (200).

Description

TECHNICAL FIELDThe present application relates to the technical field of batteries, particularly to a cover plate assembly, a battery, and a battery module.PRIOR ARTIn the relevant art, the lower annular plastic standing surface of the cover plate assembly of the battery is designed as a straight surface and does not have a guide for insertion into the housing.DISCLOSURE OF THE INVENTIONFirst, the present application provides a cover plate assembly comprising: a cover plate; an insulator including a connecting portion and a guiding portion, the connecting portion being attached to the cover plate; the guiding portion being annular and being connected to a side of the connecting portion facing away from the lid in a first direction, the guiding portion including a cavity, the guiding portion including a guiding surface facing away from the cavity, the guiding surface being an inclined surface; wherein the orthogonal projection of the guiding surface in the first direction is entirely inside the connecting portion.Second, the present application provides a battery that includes a cover plate assembly.Third, the present application provides a battery module including a battery. Advantageous Technical EffectIn the exemplary embodiments of the present application, the arrangement of a guide running surface on the guide section has the effect that, when the cover plate is attached to the housing, the insulating piece located on the cover plate and facing the housing in the first direction initially enters the housing. In this case, the guide running surface designed as an inclined surface produces a certain distance from the housing, so that the guide section does not cause damage to the housing when it is inserted into the housing. At the same time, the insertion of the guide section into the housing ensures a precise alignment between the cover plate and the housing during the assembly process in order to avoid collisions between the cover plate and the housing, which could lead to damage and impair the assembly.SUMMARY OF THE INVENTIONFIG. 1 is a cross-sectional diagram of the cover plate assembly provided in the embodiments of the present application; FIG. 2 is a cross-sectional diagram of the insulator provided in the embodiments of the present application; FIG. 3 is an enlarged view of the region A in FIG. 2 ; FIG. 4 is a structural diagram of the insulator provided in the embodiments of the present application.Reference numerals denote reference numerals1000, Cover plate assembly; 100, insulating piece; 200, cover plate; 1, connecting portion; 2, guide portion; 3, cavity; 21, guide surface; 22, first surface; 23, pressure surface; 4, groove; 5, through hole; 6, pressure relief hole.CONCRETE EMBODIMENTSIn the specification of the present application, unless expressly stated otherwise, the term "connected", "linked" or "fixed" is to be understood in a broad sense, that is, it may be either a fixed connection or a detachable connection or a unit; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection via an intermediate medium; it may mean the communication within two elements or the alternation ratio between two elements. For a person skilled in the art, the specific meaning content of the above terms in this application will be understood depending on the concrete circumstances.In this application, unless expressly stated otherwise, a first feature "above" or "below" a second feature means both direct contact of the first and second features and contact via an additional feature between the two features. Also, "above", "above", and "above" a second feature includes that the first feature is directly above or obliquely above the second feature, and that the horizontal height of the first feature is greater than that of the second feature. "below", "below", and "below" a second feature means that the first feature is directly below or obliquely below the second feature, and that the horizontal height of the first feature is less than that of the second feature.In the description of the present exemplary embodiments, the terms "upper", "lower", "left", "right", "front", "rear", etc. refer to the orientations or positions illustrated in the drawings and serve for simplified description and handling without this indicating or suggesting that the device or element in question has a specific orientation or has to be constructed and operated in a specific orientation. Therefore, they should not be understood as limiting the present application. Moreover, the terms "first" and "second" are used merely for differentiation purposes and have no special meaning.The present application provides an insulator, and FIGS. 1 to 4 show an embodiment of the present application. As illustrated in the drawings, the X direction is the first direction. Hereinafter, the description will be made with respect to the first direction X.Referring to FIGS. 1 to 4, the cover plate assembly 1000 includes the cover plate 200 and the insulator 100, the insulator 100 including a connection portion 1 and a guide portion 2. The connecting portion 1 is mounted on the cover plate 200 of the battery; the guide portion 2 is formed annularly and connected to the housing-opposite side of the connecting portion 1 in the first direction X. The guide portion 2 has a cavity 3 and includes a guide surface 21 facing away from the cavity 3, the guide surface 21 being an inclined surface. In this case, the orthogonal projection of the guide running surface 21 in the first direction X is located completely within the connecting section 1.In the exemplary embodiments of the present application, the arrangement of the guide running surface 21 on the guide portion 2 ensures that, when the cover plate 200 is mounted on the housing, the insulating piece 100 located on the cover plate 200 and facing the housing in the first direction X first enters the housing. A certain distance is thereby created between the inclined guide running surface 21 and the housing, so that the guide section 2 does not cause any damage during the insertion into the housing. Moreover, inserting the guide portion 2 into the housing ensures the exact alignment between the cover plate 200 and the housing during the assembly process in order to avoid collisions between the cover plate 200 and the housing, which could lead to damage and impair the assembly of the cover plate 200 and the housing.It should be understood that after the battery is fully assembled, the cavity 3 of the insulator 100 provides space for components such as the battery tabs and bus bars. In this embodiment, the guide portion 2 is formed annularly and encloses, together with the connection portion 1, components such as the tabs and busbars, thereby keeping these parts spaced from the housing of the battery and the cover plate 200 to avoid the risk of the spike discharge between the tabs, busbars and the housing or the cover plate 200.The connecting portion 1 is provided with an annular groove 4 on the side facing the housing 200 in the first direction X. The groove 4 is arranged in the first direction X corresponding to the guide portion 2. The groove 4 is arranged opposite the guide portion 2 in the first direction X. During the assembly process between the cover plate 200 of the battery and the case, the guide portion 2 is pressed against the electrode core located in the case of the battery, and the groove 4 provides a deformation space when the electrode core is pressed by the guide portion 2. This prevents the guide portion 2 from expanding toward the battery case due to the pressure between the electrode core and the cover plate 200 and thus pressing the battery case, which may lead to failure in welding. In addition, this can prevent the insulator 100 from pressing the welding region between the case of the battery and the cover plate 200 by thermal expansion when welding around the cover plate 200.The exact position of the guide portion 2 and the groove 4 on the connecting portion 1 is not limited as long as it is ensured that the groove 4 is arranged opposite the guide portion 2 in the first direction X, so that the groove 4 provides the guide portion 2 with the retraction space. Therefore, the position of the groove 4 and the guide portion 2 can be located either near the center of the connecting portion 1 or near the edge of the connecting portion 1. In some embodiments of the present application, the guide portion 2 and the groove 4 are both disposed near the edge of the connecting portion 1, so that not only is it ensured that the groove 4 provides the retracting space to the guide portion 2 but also the volume of the cavity 3 is increased.In some embodiments of the present application, the guide portion 2 and the groove 4 are both located at the edge of the connecting portion 1.The structure of the groove 4 is also not limited, and may be a rectangular groove, an arc-shaped groove, or a special shape groove. In one embodiment of the present application, the groove 4 is formed in an arc shape. At this time, an arcuate groove 4 is less susceptible to cracks in the wall parts of the groove as compared with a rectangular groove when the guide portion 2 is deformed while the insulator 100 contracts.See FIG. 3 ; in some exemplary embodiments of the present application, the groove 4 is formed in an arc shape, wherein a distance from the groove bottom to the groove opening is D. The following applies here: 0.3 mm≤D≤0.5 mm. The distance D can be defined as the straight distance between the wall of the groove 4 and the surface of the groove opening at a specific location of the groove 4; it can also be the distance from the wall of the groove 4 to a specific point at the groove opening.In an embodiment of the present application, the distance of the wall of the groove 4 to point B is equal, i.e. this distance is D. If D is less than 0.3 mm, the size of the groove 4 is not sufficient to accommodate the deformation of the insulator piece 100 caused by pressure, which can lead to damage to the housing of the battery and thus to a welding defect. If D is larger than 0.5 mm, the size of the groove 4 is too large, resulting in insufficient structural strength of the insulator 100.The guide portion 2 has a length H in the first direction X; where H satisfies the following condition: 1.8 mm≤H≤2.5 mm. It is to be understood that the length H of the guide portion 2 in the first direction X influences the volume of the cavity 3 formed thereby. Therefore, the design range for H in this embodiment is between 1.8 mm and 2.5 mm, which provides an air chamber space for the insulator 100. If H is larger than 2.5 mm, it adversely affects the increase in the capacity of the battery. If H is less than 1.8 mm, overflow may occur during the battery filling process.Furthermore, the guide portion 2 is formed annularly and comprises the guide surface 21, wherein the orthogonal projection of the guide surface 21 in the first direction X lies completely within the connecting part 1. This can be understood to mean that the guide portion 2 is designed conically in the first direction X in the direction from the connecting part 1. This configuration enables the guide portion 2 to have a guiding function in mounting the lid 200 on the case of the battery.Here, an outer diameter of the guide portion 2 on a side facing the cover plate 200 in the first direction is referred to as L 1, and an outer diameter of the guide portion 2 on a side facing away from the cover plate 200 in the first direction is referred to as L 2, an angle between the guide surface 21 and the first direction is referred to as A; wherein L 1, L 2, H, and A satisfy a following condition:The values of L 1, L 2 and H allow the angle A of the guide surface 21 to be determined with respect to the first direction X.Moreover, the length L 1 corresponds to the outer diameter size of the cover 200 of the battery. Therefore, the length of L 1 can be calculated by setting the one-sided distance between the insulator 100 and the cover 200. Here, the length L 1 is the outer diameter of the guide portion 2 on the side facing the cover plate 200 in the first direction X, and is thus also the outer diameter of the insulating piece 100.The outer diameter of the cover 200 is referred to as D 1, the one-side distance between the insulating piece 100 and the cover 200 is referred to as d 1, and the coaxiality of the insulating piece 100 with the cover 200 during the assembly process is referred to as g 1. The amount of deformation occurring between the cover 200 and the housing after assembly is referred to as g2. Considering the tolerances of the outer diameter of the insulator 100 and the cover 200, the tolerance of the one-sided clearance value g3 is calculated using the root mean square method. The following applies here: 0≤gl≤0.5 mm, 0≤g2≤0.2 mm and 0≤g3≤0.1 mm. This results in the one-sided distance d1=g1+g2+g3and L1=D1-2d1.Please refer to FIGS. 2 to 3, the guide portion 2 also comprises a first surface 22 enclosing a cavity 3 and a pressing surface 23 located on the side of the guide portion facing away from the cover. The pressure surface 23 connects the first surface 22 to the guide surface 21, and a pressure surface 23 is formed on the guide portion 2. In comparison with the end formed on the side of the guide portion 2 facing away from the connection unit 1, via which the guide portion 2 is supported against the electrode core, the arrangement of the supporting surface 23 ensures that the contact area between the insulating piece 100 and the electrode core increases. This not only leads to a good fixing effect, but also reduces the pressure of the insulator 100 on the electrode core to avoid damage to the electrode core.The distance L of the connection between the pressing surface 23 and the first surface 22 and the connection between the pressing surface 23 and the guide surface 21 is L; where L satisfies the condition: 0.5 mm≤L≤0.8 mm. If L is less than 0.5 mm, the area of the pressing surface 23 is too small, resulting in that the pressure of the insulator 100 on the electrode core is too high at the time of assembly and the electrode core may be injured. If L is larger than 0.8 mm, the requirement for the assembly accuracy between the bus bar and the insulator 100 increases, which increases the risk of an assembly error.It is understood that through holes 5 for the passage of the poles and pressure relief holes 6 connected to the pressure relief valve on the cover plate 200 are also provided in the insulator 100.Referring to FIG. 1, the present application further provides a battery including a cover plate assembly. The cover plate assembly 1000 is constructed as described above. Since the battery adopts all the technical features of the above-described embodiments, it has at least the technical advantages achieved by the above-mentioned embodiments, which are not repeated here in detail.The present application also provides a battery pack including the battery. The battery is constructed as described above. Since the battery pack adopts all the technical features of the above-described embodiments, it has at least the technical advantages achieved by the above-mentioned embodiments, which are not repeated here in detail.

Claims

A cover plate assembly comprising: a cover plate (200); an insulator (100) comprising a connection portion (1) and a guide portion (2), wherein the connection portion (1) is attached to the cover plate (200); the guide portion (2) is annular and is connected to a side of the connection portion (1) facing away from the cover (200) in a first direction, wherein the guide portion (2) comprises a cavity (3), wherein the guide portion (2) comprises a guide running surface (21) facing away from the cavity (3), wherein the guide running surface (21) is an inclined surface; wherein an orthogonal projection of the guide running surface (21) in a first direction lies completely within the connection portion (1), wherein the first direction runs perpendicular to the cover plate (200).Cover plate assembly according to claim 1, wherein on the side of the connecting portion (1) facing the cover (200) in the first direction a groove (4) is provided which is formed annularly; wherein the groove (4) corresponds to the guide portion (2) in the first direction.The cover plate assembly according to claim 2, wherein the guide portion (2) and the groove (4) are both formed at the edge of the periphery of the connecting portion (1).Cover plate assembly according to claim 2 or 3, wherein the groove (4) is formed in an arc shape.The cover plate assembly according to any one of claims 1 to 4, wherein a length of the guide portion (2) in the first direction is H; wherein H satisfies a condition 1.8 mm ≤ H ≤ 2.5 mm.The cover plate assembly according to claim 5, wherein an outer diameter of the guide portion (2) on a side facing the cover plate (200) in the first direction is referred to as L1, and an outer diameter of the guide portion (2) on a side facing away from the cover plate (200) in the first direction is referred to as L2, wherein an angle between the guide surface (21) and the first direction is referred to as A; wherein L1, L2, H, and A satisfy a following condition: A = tan - 1 L 1 - L 2 2 H. The cover plate assembly according to any one of claims 1 to 6, wherein the guide portion (2) further comprises a first surface (22) enclosing the cavity (3) and a pressing surface (23) located on a side of the guide portion (2) facing away from the cover plate; wherein the pressing surface (23) connects the first surface (22) and the guide running surface (21).The cover plate assembly according to claim 7, wherein a distance between the connection of the pressure surface (23) to the first surface (22) and the connection of the pressure surface (23) to the guide tread (21) is referred to as L; wherein L satisfies a condition 0.5 mm ≤ L ≤ 0.8 mm.A battery comprising the cover plate assembly (1000) of any one of claims 1 to 8.A battery module comprising the battery of claim 9.

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