Battery shell and electric equipment

Abstract

The utility model discloses a battery case and electric equipment, the battery case comprises: a case in which an accommodating cavity is arranged; the cover plate is connected with the shell to seal the containing cavity, an extension part is arranged on the side, facing the shell, of the cover plate, the extension part is located in the containing cavity, and the extension part is connected with the inner circumferential wall of the shell; at least one groove is formed in one of the inner peripheral wall of the shell and the outer peripheral wall of the extension part, at least one bulge is arranged on the other one, and the groove is matched with the bulge. According to the battery shell disclosed by the utility model, one of the inner peripheral wall and the extension part of the shell is provided with at least one groove, and the other one of the inner peripheral wall and the extension part of the shell is provided with at least one bulge, so that when the cover plate and the shell are assembled, the shell and the cover plate can be further connected in a limiting manner through the bulge and the groove, and the matching precision of the shell and the cover plate is improved; the cover plate is effectively prevented from rotating and misplacing relative to the shell, occlusion damage and gouge deformation are avoided, and the yield of the welding procedure of the shell and the cover plate is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of battery manufacturing, and more specifically, to a battery case and an electrical equipment using the same. Background Art

[0002] In the prior art, the housing and the cover are directly installed without other limiting structures, and the welding quality completely depends on the cooperation between the housing and the cover. The risk of misalignment between the housing and the cover is high, and the welding yield is low. Or a thread is provided on the side surface of the cover for thread engagement with the inner wall thread of the housing, but bite damage and bruise deformation are likely to occur. Summary of the Utility Model

[0003] An object of the utility model is to provide a new technical solution for a battery case and an electrical equipment using the same, which can at least solve the problems of high risk of misalignment between the housing and the cover and easy occurrence of bite damage in the prior art.

[0004] In a first aspect of the utility model, there is provided a battery case, including: a housing having a receiving cavity therein; a cover plate connected to the housing to enclose the receiving cavity, an extension portion being provided on a side of the cover plate facing the housing, the extension portion being located in the receiving cavity and connected to an inner peripheral wall of the housing; at least one groove is provided on one of the inner peripheral wall of the housing and the outer peripheral wall of the extension portion, and at least one protrusion is provided on the other, and the groove and the protrusion are adapted to each other.

[0005] Optionally, at least one of the grooves is provided on the outer peripheral wall of the extension portion, and at least one of the protrusions is provided on the inner peripheral wall of the housing, and the groove and the protrusion are adapted to each other.

[0006] Optionally, the protrusion extends in a first direction, and the groove extends in the first direction, and the first direction is the direction in which the cover plate faces the housing.

[0007] Optionally, the extension length of the protrusion is not less than the extension length of the groove.

[0008] Optionally, the extension length of the groove is denoted as H1, where 1 mm ≤ H1 ≤ 5 mm, and / or the extension length of the protrusion is denoted as H2, where 1 mm ≤ H2 ≤ 5 mm.

[0009] Optionally, the cross-sectional width of the groove is denoted as W1, where 0 mm < W1 ≤ 0.2 mm, and the cross-sectional width of the protrusion is denoted as W2, where 0 mm < W2 ≤ 0.2 mm.

[0010] Optionally, the depth of the groove is denoted as D1, where 0.1 mm ≤ D1 ≤ 0.2 mm, and the depth of the protrusion is denoted as D2, where 0.1 mm ≤ D2 ≤ 0.2 mm.

[0011] Optionally, the included angle between the edge of the groove and the arc section of the extension part is denoted as β1, where 45° ≤ β1 ≤ 90°, and the included angle between the edge of the protrusion and the tangent line of the inner surface of the housing is denoted as β2, where 45° ≤ β2 ≤ 90°.

[0012] Optionally, the concave angle of the groove is denoted as α1, where 0° < α1 ≤ 180°, and the convex angle of the protrusion is denoted as α2, where 0° ≤ α2 ≤ 180°.

[0013] Optionally, the shape of the groove is semi-circular, triangular or trapezoidal, and the shape of the protrusion corresponds to the shape of the groove.

[0014] Optionally, the numbers of the grooves and the protrusions are both multiple. The multiple grooves are evenly distributed at intervals along the outer peripheral surface of the extension part, and the multiple protrusions are evenly distributed at intervals along the inner peripheral surface of the housing.

[0015] In the second aspect of the present utility model, there is provided an electrical device including the battery housing described in the above embodiment.

[0016] In the battery housing of the present utility model, by providing at least one groove on one of the inner peripheral wall of the housing and the extension part, and at least one protrusion on the other, when the cover plate is assembled with the housing, the housing and the cover plate can be further limited and connected through the protrusion and the groove, improving the matching accuracy between the housing and the cover plate, effectively preventing the cover plate from rotating and misaligning relative to the housing, avoiding bite damage and bruising deformation, and improving the yield rate of the welding process between the housing and the cover plate.

[0017] Other features and advantages of the present utility model will become clear through the following detailed description of the exemplary embodiments of the present utility model with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings incorporated in and constituting a part of this specification illustrate embodiments of the present utility model and, together with the description, serve to explain the principles of the present utility model.

[0019] Figure 1 is an exploded view of the structure of a battery housing according to Embodiment 1 of the present utility model;

[0020] Figure 2 is another exploded view of the structure of a battery housing according to Embodiment 1 of the present utility model;

[0021] Figure 3 is a sectional view of a battery housing according to Embodiment 2 of the present utility model;

[0022] Figure 4 is a schematic structural view of the housing according to Embodiment 2 of the present utility model;

[0023] Figure 5 is a sectional view of the cover plate according to Embodiment 2 of the present utility model;

[0024] Figure 6 is a sectional view of the housing according to Embodiment 2 of the present utility model.

[0025] Reference numerals:

[0026] housing 10;

[0027] cover plate 20; extension portion 21;

[0028] protrusion 31; groove 32. Detailed implementation manners

[0029] Now, various exemplary embodiments of the present utility model will be described in detail with reference to the accompanying drawings. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present utility model.

[0030] The following description of at least one exemplary embodiment is merely illustrative in nature and in no way serves as a limitation on the present utility model and its application or use.

[0031] Techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the said techniques, methods, and devices should be regarded as part of the specification.

[0032] In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

[0033] It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0034] In the description and claims of the present utility model, features related to the terms "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "a plurality" is two or more. In addition, "and / or" in the description and claims means at least one of the connected objects, and the character " / " generally means an "or" relationship between the associated objects before and after.

[0035] In the description of the present utility model, it should be understood that if terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are involved, the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0036] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" involved should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0037] The following specifically describes the battery case according to the embodiments of the present utility model with reference to the drawings.

[0038] As Figures 1 to 4 shown, the battery case according to the embodiments of the present utility model includes a housing 10 and a cover plate 20.

[0039] Specifically, a receiving cavity is provided inside the housing 10; the cover plate 20 is connected to the housing 10 to close the receiving cavity. An extension portion 21 is provided on the side of the cover plate 20 facing the housing 10. The extension portion 21 is located in the receiving cavity and is connected to the inner peripheral wall of the housing 10. At least one groove 32 is provided on one of the inner peripheral wall of the housing 10 and the outer peripheral wall of the extension portion 21, and at least one protrusion 31 is provided on the other, and the groove 32 and the protrusion 31 are adapted to each other.

[0040] In other words, referring to Figures 1 to 4, the battery case according to the embodiment of the present utility model mainly consists of a housing 10 and a cover plate 20. Among them, a receiving cavity for accommodating other battery structures is provided inside the housing 10. The cover plate 20 is connected to the housing 10 to enclose the receiving cavity. An extension portion 21 is provided on one side of the cover plate 20 facing the housing 10, and the extension portion 21 can be designed as a stepped structure. When the cover plate 20 is covered on the housing 10, the extension portion 21 is located in the receiving cavity of the housing 10. The extension portion 21 can be connected to the inner peripheral wall of the housing 10. Among them, the inner peripheral wall of the housing 10 can be understood as the wall surface of the housing 10 facing the enclosed receiving cavity, and the inner peripheral wall faces the extension portion 21. The outer peripheral wall of the extension portion 21 can be understood as the wall surface of the extension portion 21 facing the inner peripheral wall of the housing 10.

[0041] At least one groove 32 is provided on one of the inner peripheral wall of the housing 10 and the outer peripheral wall of the extension portion 21, and at least one protrusion 31 is provided on the other. For example, referring to Figure 1 and Figure 2 as shown, at least one groove 32 is provided on the inner peripheral wall of the housing 10, and at least one protrusion 31 is provided on the outer peripheral wall of the extension portion 21. Or, referring to Figure 3 and Figure 4 , at least one protrusion 31 is provided on the inner peripheral wall of the housing 10, and at least one groove 32 is provided on the outer peripheral wall of the extension portion 21. Each groove 32 and each protrusion 31 correspond to each other and are adaptively connected to realize the connection between the cover plate 20 and the housing 10. It should be noted that the adaptation between the groove 32 and the protrusion 31 includes but is not limited to the adaptation of shape, quantity, position, etc.

[0042] In the present utility model, the cover plate 20 can be covered on the housing 10. When the cover plate 20 is covered on the housing 10, the extension portion 21 extends into the housing 10. By providing at least one groove 32 on one of the inner peripheral wall of the housing 10 and the extension portion 21, and at least one protrusion 31 on the other, during the process of the housing 10 and the cover plate 20 being covered and connected, the limiting of the housing 10 and the cover plate 20 is further realized, the matching accuracy between the housing 10 and the cover plate 20 is improved, effectively preventing the cover plate 20 from rotating and misaligning relative to the housing 10, and there will be no bite damage and knock damage and deformation, improving the yield rate of the welding process between the housing 10 and the cover plate 20.

[0043] In the present utility model, through the cooperation between the protrusion 31 and the groove 32, it is ensured that the assembly of the housing 10 and the cover plate 20 is more convenient, and the thickness of the matching part of the housing 10 is the same as that of the whole housing 10. There is no weak area in the housing 10, improving the structural strength after the subsequent welding of the housing 10 and the cover plate 20.

[0044] Thus, for the battery case according to the embodiment of the present utility model, by providing at least one groove 32 on one of the inner peripheral wall of the housing 10 and the extension portion 21, and at least one protrusion 31 on the other, when the cover plate 20 is assembled with the housing 10, the housing 10 and the cover plate 20 can be further limited and connected through the protrusion 31 and the groove 32, improving the matching accuracy between the housing 10 and the cover plate 20, effectively preventing the cover plate 20 from rotating and misaligning relative to the housing 10, avoiding bite damage and bruise deformation, and improving the yield rate of the welding process between the housing 10 and the cover plate 20.

[0045] According to an embodiment of the present utility model, at least one groove 32 is provided on the outer peripheral wall of the extension portion 21, and at least one protrusion 31 is provided on the inner peripheral wall of the housing 10, and the groove 32 and the protrusion 31 are adapted to each other.

[0046] That is to say, as Figure 3 and Figure 4 shown, at least one groove 32 is provided on the outer peripheral wall of the extension portion 21, and at least one protrusion 31 is provided on the inner peripheral wall of the housing 10, and the groove 32 and the protrusion 31 are adapted to each other. When the cover plate 20 is covered on the housing 10, the extension portion 21 on the cover plate 20 extends into the housing 10, and the groove 32 on the extension portion 21 is correspondingly connected with the protrusion 31 on the inner peripheral surface of the housing 10, realizing further limitation between the housing 10 and the cover plate 20, improving the matching accuracy between the housing 10 and the cover plate 20, effectively preventing the cover plate 20 from rotating and misaligning relative to the housing 10, avoiding bite damage and bruise deformation, and improving the yield rate of the welding process between the housing 10 and the cover plate 20.

[0047] In the present utility model, the protrusion 31 of the housing 10 is matched with the groove 32 of the cover plate 20, ensuring that the assembly of the housing 10 and the cover plate 20 is more convenient, and the thickness of the matching part of the housing 10 is the same as that of the whole housing 10. There is no weak area in the housing 10, improving the structural strength after the subsequent welding of the housing 10 and the cover plate 20.

[0048] According to an embodiment of the present utility model, the protrusion 31 can extend along a first direction, and the groove 32 can extend along the first direction, where the first direction can be understood as the direction in which the cover plate 20 faces the housing 10.

[0049] In the present utility model, referring to Figure 1 , the housing 10 and the cover plate 20 are respectively configured as cylinders, and this battery case can be applied to cylindrical batteries, for example, cylindrical lithium-ion power batteries. The first direction can be understood as the circumferential direction of the housing 10 (such as Figure 1In the direction of the arrow (in the figure), the protrusion 31 can extend along the axial direction of the housing 10, and the groove 32 can extend along the axial direction of the cover plate 20. When the cover plate 20 is covered on the housing 10, the extension portion 21 on the cover plate 20 extends into the housing 10, and the groove 32 on the extension portion 21 is correspondingly connected to the protrusion 31 on the inner peripheral surface of the housing 10, realizing further limitation of the housing 10 and the cover plate 20, improving the matching accuracy between the housing 10 and the cover plate 20, effectively preventing the cover plate 20 from rotating and misaligning relative to the housing 10, avoiding bite damage and bruise deformation, and improving the yield of the welding process of the housing 10 and the cover plate 20.

[0050] According to an embodiment of the present invention, the extension length of the protrusion 31 is not less than the extension length of the groove 32, ensuring that the protrusion 31 can effectively limit the groove 32, improving the matching accuracy between the housing 10 and the cover plate 20, effectively preventing the cover plate 20 from rotating and misaligning relative to the housing 10, avoiding bite damage and bruise deformation, and improving the yield of the welding process of the housing 10 and the cover plate 20.

[0051] According to an embodiment of the present invention, the extension length of the protrusion 31 is equal to the extension length of the groove 32. The extension length of the groove 32 is understood as the depth of the groove 32. By setting the extension lengths of the protrusion 31 and the groove 32 to be the same, the most effective limitation of the cover plate 20 and the housing 10 is ensured, and the material cost is saved.

[0052] According to an embodiment of the present invention, the extension length of the groove 32 is denoted as H1, where 1 mm ≤ H1 ≤ 5 mm, and the extension length of the protrusion 31 is denoted as H2, where 1 mm ≤ H2 ≤ 5 mm.

[0053] That is to say, as Figure 4 and Figure 5 shown, the extension portion 21 of the cover plate 20 is recessed to form a groove 32, and the height dimension range of the groove 32 between the upper and lower surfaces of the extension portion 21 is 1 mm ≤ H1 ≤ 5 mm. The dimension range of the protrusion 31 on the inner ring of the housing 10 in the height of the housing 10 (the extension length of the protrusion 31) is 1 mm ≤ H2 ≤ 5 mm. In the present invention, the height dimensions of the groove 32 and the protrusion 31 can be determined according to the overall thickness of the cover plate 20, facilitating the assembly of the housing 10 and the cover plate 20. It should be noted that the height dimensions of the groove 32 and the protrusion 31 can be as small as possible. Therefore, the height dimension range can be 1 mm ≤ H ≤ 5 mm. Exceeding the upper limit of 5 mm will affect the convenience of assembling the housing 10 and the cover plate 20. At the same time, considering that the overall thickness of the cover plate 20 cannot be too thick, otherwise it will affect the overall energy density of the battery.

[0054] In some specific embodiments of the present utility model, the cross-sectional width of the groove 32 is denoted as W1, where 0 mm < W1 ≤ 0.2 mm, and the cross-sectional width of the protrusion 31 is denoted as W2, where 0 mm < W2 ≤ 0.2 mm.

[0055] In other words, as Figure 4 and Figure 5 shown, the width range of the groove 32 is 0 mm < W1 ≤ 0.2 mm, and the width range of the protrusion 31 is 0 mm < W2 ≤ 0.2 mm. The widths of the groove 32 and the protrusion 31 can be as small as possible because the stamping technology is used in the manufacturing process of the housing 10 and the cover plate 20, and the groove 32 formed by large-area stamping will affect the rigidity of the overall structure.

[0056] According to an embodiment of the present utility model, the depth of the groove 32 is denoted as D1, where 0.1 mm ≤ D1 ≤ 0.2 mm, and the depth of the protrusion 31 is denoted as D2, where 0.1 mm ≤ D2 ≤ 0.2 mm.

[0057] That is to say, as Figure 4 and Figure 5 shown, the depth range of the groove 32 is 0.1 mm ≤ D1 ≤ 0.2 mm, and the depth range of the protrusion 31 is 0.1 mm ≤ D2 ≤ 0.2 mm. The depths of the groove 32 and the protrusion 31 can be kept consistent. Since the gap is about 0.1 - 0.2 mm after the cylindrical pole core is assembled into the housing 10, therefore, within the range of 0.1 mm ≤ D1 ≤ 0.2 mm for the depths of the groove 32 and the protrusion 31, it does not affect the assembly of the pole core.

[0058] According to an embodiment of the present utility model, the angle between the edge of the groove 32 and the arc tangent plane of the extension part 21 is denoted as within the range of β1, where 45° ≤ β1 ≤ 90°, and the angle between the edge of the protrusion 31 and the tangent line of the inner surface of the housing 10 is denoted as β2, where 45° ≤ β2 ≤ 90°.

[0059] That is to say, referring to Figure 4 and Figure 5 , the angle range between the edge of the groove 32 and the arc tangent plane of the extension part 21 can be 45° ≤ β1 ≤ 90°. The angle between the edge of the protrusion 31 and the tangent line of the inner surface of the housing 10 can be 45° ≤ β2 ≤ 90°. This angle range facilitates the assembly of the cover plate 20 and the housing 10 and improves the assembly efficiency of the cover plate 20 and the housing 10.

[0060] According to an embodiment of the present utility model, the concave angle of the groove 32 is denoted as α1, where 0° < α1 ≤ 180°, and the convex angle of the protrusion 31 is denoted as α2, where 0° ≤ α2 ≤ 180°.

[0061] In other words, the range of the concave angle of the groove 32 on the cover plate 20 can be 0° ≤ α1 ≤ 180°, and the range of the protruding angle of the protrusion 31 in the housing 10 can be 0° ≤ α2 ≤ 180° (see Figure 6 ), which facilitates having a certain inclination angle of the groove 32 and the protrusion 31 relative to the plane, and improves the stability of the assembly connection between the cover plate 20 and the housing 10.

[0062] According to an embodiment of the present invention, the shape of the groove 32 can be semi-circular, triangular or trapezoidal, and the shape of the protrusion 31 corresponds to the shape of the groove 32. By setting the groove 32 as semi-circular, triangular or trapezoidal, the stability of the assembly connection between the cover plate 20 and the housing 10 is further improved. Of course, the shapes of the groove 32 and the protrusion 31 are not limited to semi-circular, triangular or trapezoidal, and other shapes that are convenient for improving the assembly stability between the cover plate 20 and the housing 10 should also fall within the protection scope of the present invention.

[0063] According to an embodiment of the present invention, the numbers of the groove 32 and the protrusion 31 are both multiple. The multiple grooves 32 are evenly distributed at intervals along the outer peripheral surface of the extension part 21, and the multiple protrusions 31 are evenly distributed at intervals along the inner peripheral surface of the housing 10.

[0064] In other words, the numbers of the groove 32 and the protrusion 31 can both be set to be multiple. The multiple grooves 32 can be evenly distributed at intervals along the outer peripheral surface of the extension part 21, and the multiple protrusions 31 can be evenly distributed at intervals along the inner peripheral surface of the housing 10.

[0065] In the present invention, the number of the grooves 32 on the cover plate 20 can be determined according to the distribution angle. The range of the distribution angle can be 30° ≤ γ ≤ 120° (see Figure 6 ), and the corresponding distribution number can be 3 ≤ Z ≤ 12. The distribution angle and number of the protrusion 31 are the same as those of the groove 32. By providing multiple grooves 32 and protrusions 31, the assembly of the cover plate 20 and the housing 10 can be further facilitated, and at the same time, the cooperation between the two can be ensured to be reliable, which is convenient for subsequent welding and sealing. The cover plate 20 and the housing 10 of the present invention are firmly connected through the one-way guiding action of the protrusion 31 and the groove 32, greatly improving the accuracy of the shell-cover cooperation, avoiding the risk of shell-cover misalignment, and effectively improving the yield rate of the shell-cover welding process.

[0066] Moreover, the multiple protrusions 31 of the housing 10 cooperate with the multiple grooves 32 of the cover plate 20, which can achieve a simpler cooperation. And the thickness of the part of the housing 10 for cooperation is the same as the overall thickness of the housing 10. There is no weak area in the housing 10, and the strength of the weld seam after welding is stronger than that of the threaded connection method.

[0067] In summary, for the battery case according to the embodiment of the present utility model, by providing at least one groove 32 on one of the inner peripheral wall of the housing 10 and the extension portion 21, and at least one protrusion 31 on the other, when the cover plate 20 is assembled with the housing 10, the housing 10 and the cover plate 20 can be further limited and connected through the protrusion 31 and the groove 32, improving the fitting accuracy between the housing 10 and the cover plate 20, effectively preventing the cover plate 20 from rotating and misaligning relative to the housing 10, avoiding bite damage and bruising deformation, and improving the yield rate of the welding process between the housing 10 and the cover plate 20.

[0068] Of course, for those skilled in the art, other structures and working principles of the battery case are understandable and achievable, and will not be elaborated in detail in the present utility model.

[0069] According to the second aspect of the present utility model, there is provided an electrical device including the battery case in the above embodiment. Since the battery case according to the embodiment of the present utility model has the above technical effects, the electrical device according to the embodiment of the present utility model should also have corresponding technical effects, that is, by adopting this battery case, the electrical device of the present utility model can effectively improve the fitting accuracy between the housing 10 and the cover plate 20, effectively prevent the cover plate 20 from rotating and misaligning relative to the housing 10, avoid bite damage and bruising deformation, improve the yield rate of the welding process between the housing 10 and the cover plate 20, and improve the finished product yield rate and service life of the electrical device.

[0070] Of course, for those skilled in the art, other structures and working principles of the electrical device are understandable and achievable, and will not be elaborated in detail in the present utility model.

[0071] Although some specific embodiments of the present utility model have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration purposes and not for limiting the scope of the present utility model. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present utility model. The scope of the present utility model is defined by the appended claims.

Claims

1. A battery shell, characterized in that: include: A housing, wherein a receiving cavity is provided in the housing; A cover plate, the cover plate is connected to the shell to close the accommodating cavity, the cover plate is provided with an extension portion on a side facing the shell, the extension portion is located in the accommodating cavity, and the extension portion is connected to the inner peripheral wall of the shell; At least one groove is arranged on one of the inner peripheral wall of the shell and the outer peripheral wall of the extension part, and at least one protrusion is arranged on the other, and the groove and the protrusion are matched.

2. The battery case according to claim 1, characterized in that: At least one groove is provided on the outer peripheral wall of the extension portion, and at least one protrusion is provided on the inner peripheral wall of the shell, and the groove is matched with the protrusion.

3. The battery case according to claim 1, characterized in that: The protrusion extends along a first direction, and the groove extends along the first direction, and the first direction is a direction in which the cover plate faces the housing.

4. The battery case according to claim 3, characterized in that: The extension length of the protrusion is not less than the extension length of the groove.

5. The battery case according to claim 3, characterized in that: The extension length of the groove is recorded as H1, wherein 1mm≤H1≤5mm, and / or the extension length of the protrusion is recorded as H2, wherein 1mm≤H2≤5mm.

6. The battery case according to claim 3, characterized in that: The cross-sectional width of the groove is recorded as W1, wherein 0mm<W1≤0.2mm, and the cross-sectional width of the protrusion is recorded as W2, wherein 0mm<W2≤0.2mm.

7. The battery case according to claim 3, characterized in that: The depth of the groove is recorded as D1, wherein 0.1 mm≤D1≤0.2 mm, and the depth of the protrusion is recorded as D2, wherein 0.1 mm≤D2≤0.2 mm.

8. The battery case according to claim 3, characterized in that: The angle between the edge of the groove and the arc section of the extension portion is recorded as β1, where 45°≤β1≤90°, and the angle between the edge of the protrusion and the tangent of the inner surface of the shell is recorded as β2, where 45°≤β2≤90°.

9. The battery case according to claim 3, characterized in that: The concave angle of the groove is recorded as α1, wherein 0°<α1≤180°, and the protruding angle of the protrusion is recorded as α2, wherein 0°≤α2≤180°.

10. The battery case according to claim 1, characterized in that: The shape of the groove is semicircular, triangular or trapezoidal, and the shape of the protrusion corresponds to the shape of the groove.

11. The battery case according to claim 1, characterized in that: There are multiple grooves and multiple protrusions. The multiple grooves are evenly distributed along the outer circumference of the extension portion, and the multiple protrusions are evenly distributed along the inner circumference of the shell.

12. An electrical equipment, characterized in that: A battery case comprising the battery case according to any one of claims 1 to 11.

Images