Battery

Abstract

The utility model discloses a battery and belongs to the technical field of lithium batteries. The battery comprises a battery cover plate, a shell and a plurality of vertical strip grooves, the battery cover plate comprises a base plate, wherein the base plate is provided with a flat plate part and a convex part along a first direction, and the convex part and the edge of the flat plate part are spaced by a set distance; the shell can be buckled with the battery cover plate, and when the shell is buckled with the battery cover plate, the inner wall of the shell is attached to the outer edge of the convex part. The multiple vertical strip grooves are formed in the outer edge of the convex part at intervals in the circumferential direction. By adopting the technology provided by the utility model, a metal molten pool is deeper in the welding process of the battery cover plate and the shell, so that the welding strength between the battery cover plate and the shell is effectively enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a battery. Background Art

[0002] Laser welding is to focus the laser beam in a small area by shaping the optical path, forming a highly concentrated heat source area in the welded part in a very short time, melting the welded objects, and thus producing strong welds and welds. At present, the welding methods between the cover and the shell of square batteries mainly use top laser welding and side laser welding.

[0003] Among them, the weld of the top laser welding is located on the top of the cover plate, and the requirements for equipment integration are relatively low. However, since the laser is facing the weld during top welding, it is easy for light to leak through the gap and burn the internal battery cells. Although side laser welding is less likely to damage the internal battery cells than top laser welding, it has higher requirements for the weld, and its welding efficiency is much lower than top laser welding. In addition, both of the above two welding methods require the formation of a heat source area with highly concentrated energy, which can easily cause deformation of the shell cover during welding.

[0004] Based on this, the current mainstream improvement methods are mostly to improve the welding method, such as increasing the welding process to at least two consecutive welding steps, adjusting the power of the welding equipment for continuous welding or adjusting the position of the heat source area formed by continuous welding to avoid the above problems, but it also leads to higher costs for battery production. Utility Model Content

[0005] The utility model provides a battery to solve the problem in the prior art that the battery is easily damaged due to top laser welding and side laser welding.

[0006] In order to solve the above technical problems, the technical solution adopted by the utility model is to provide a battery, which includes: a battery cover, a shell and a plurality of vertical grooves.

[0007] The battery cover includes a substrate, the substrate is provided with a flat plate portion and a convex portion spaced apart from the edge of the flat plate portion by a set distance along a first direction; the shell can be buckled with the battery cover, wherein when the shell is buckled with the battery cover, the inner wall of the shell is in contact with the outer edge of the convex portion. A plurality of vertical grooves are spaced apart along the circumferential direction at the outer edge of the convex portion.

[0008] Compared with the prior art, the technical solution provided by the utility model has the following beneficial effects:

[0009] By arranging a plurality of vertical grooves on the outer edge of the convex portion of the battery cover, during the welding process of the battery cover and the shell, the solder used for welding can penetrate deeper into the shell along the vertical grooves, that is, the metal molten pool is deeper during the welding process, thereby effectively enhancing the welding strength between the battery cover and the shell.

[0010] Among them, setting up multiple vertical grooves can also effectively increase the weld area, allowing more liquid metal to penetrate into the weld, making the molten weld pool fuller, thereby effectively making the battery weld easier to meet the requirements of side laser welding and improving the efficiency of side laser welding.

[0011] In addition, compared with the current method of adjusting the welding process and changing the power of the welding equipment, providing vertical grooves at the fitting part between the convex part of the battery cover and the shell can effectively enhance the welding effect and reduce the production cost of the battery.

[0012] In some embodiments, when the battery cover is buckled with the shell, the flat plate portion of the battery cover protrudes from the shell by 0.1 mm to 0.5 mm along the first direction.

[0013] By adopting the above technical solution, the thickness of the flat plate part of the battery cover is increased, so that the flat plate part is 0.1mm to 0.5mm higher than the shell after the battery cover is buckled with the shell, which can effectively avoid deformation of the battery cover caused by the heat source area with highly concentrated energy during welding.

[0014] In some embodiments, the protrusion of the battery cover includes a first step and a second step, the outer edge of the first step is bent and connected to the outer edge of the second step, and the first step is away from the flat plate portion along the first direction; wherein the vertical groove runs along the first step through the second step to the flat plate portion.

[0015] The above technical solution is adopted, and the first step and the second step are connected in a bent manner, that is, the connection between the first step and the second step is set as a bevel, so that when the convex part of the battery cover is buckled into the shell, it can be more easily pressed into the shell and firmly connected with the shell. Among them, the vertical groove extends along the bevel to the flat plate part, which is also more convenient for the infiltration of liquid metal during the welding process.

[0016] In some embodiments, the projection shape of the vertical groove along the first direction is V-shaped or water drop-shaped.

[0017] With the above technical solution, the shape of the vertical groove can be a V-shaped groove or a teardrop-shaped groove, wherein the V-shaped groove has a larger area where the liquid metal fits inside the shell (i.e., a larger weld), and the teardrop-shaped groove has more liquid metal inside the shell, and has a smaller area where the liquid metal fits inside the shell (i.e., a smaller weld) than the V-shaped groove. By adjusting the shape of the vertical groove, the size of the weld area can be effectively controlled.

[0018] In some embodiments, when the vertical groove is V-shaped, the depth of the vertical groove located at the second step along the second direction is 0.1 mm to 0.3 mm.

[0019] In some embodiments, when the vertical groove is a teardrop shape, the depth of the vertical groove located on the second step along the second direction is 0.2 mm to 0.4 mm.

[0020] In some embodiments, a plurality of the vertical grooves are located at the outer edge of the protrusion and are arranged at the same interval.

[0021] In some embodiments, when the shell is welded to the battery cover, the angle between the shell and the external laser head is 30° to 70°.

[0022] By adopting the above technical solution, when the angle between the laser head and the shell is set to 30° to 70°, the light spot can be effectively elongated, so that the weld area covered by the laser is wider, thereby reducing the problem of laser entering the shell and burning the battery inside the shell due to refraction of the laser in the gap.

[0023] In some embodiments, the battery cover plate includes a positive electrode cover plate and a negative electrode cover plate, the positive electrode cover plate includes a fixing bracket and a welding copper plate, the fixing bracket is connected to the protrusion of the substrate along the first direction, the welding copper plate is located on the side away from the flat plate portion along the first direction and is fixed to the fixing bracket; the negative electrode cover plate and the positive electrode cover plate are respectively buckled on both sides of the shell along the first direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work, among which:

[0025] Figure 1 It is a three-dimensional structural schematic diagram of an embodiment of a battery provided by the utility model;

[0026] Figure 2This is a fracture view of an embodiment of a battery cover of a battery provided by the utility model;

[0027] Figure 3 It is a three-dimensional structural schematic diagram of an embodiment of a battery cover plate of a battery provided by the utility model;

[0028] Figure 4 yes Figure 3 A magnified view of the local structure of part A;

[0029] Figure 5 It is a structural schematic diagram of an embodiment of a V-shaped vertical groove of a battery provided by the utility model;

[0030] Figure 6 It is a structural schematic diagram of an embodiment of a water drop-shaped vertical groove of a battery provided by the utility model;

[0031] Figure 7 The utility model is a top view of an embodiment of a positive electrode cover plate of a battery provided by the utility model.

[0032] In the figure:

[0033] Battery cover plate—10; substrate—11; flat plate portion—110; convex portion—111; first step—112; second step—113; positive electrode cover plate—12; fixing bracket—120; welding copper plate—121; negative electrode cover plate—13; shell—20; vertical groove—30. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, rather than all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0035] In order to facilitate the subsequent description, before describing the specific structure of the battery, this application first combines Figure 1 A first direction (Y), a second direction (Z), and a third direction (X) are defined. The first direction is the length direction of the battery when it is normally placed, such as the Y direction; the second direction is the height direction of the battery when it is normally placed, such as the Z direction; and the third direction is the width direction of the battery when it is normally placed, such as the X direction. In this application, the first direction (Y), the second direction (Z), and the third direction (X) are perpendicular to each other.

[0036] It can be understood that the mutual perpendicularity in the present application is not absolute perpendicularity, and the approximate perpendicularity caused by processing errors and assembly errors (for example, the angle between two structural features is 89.9°) is also within the range of mutual perpendicularity in the present application.

[0037] See also Figures 1 to 3 As shown, Figure 1 A schematic diagram of the three-dimensional structure of an embodiment of a battery provided by the present application is shown; Figure 2 A fracture view of an embodiment of a battery cover plate 10 of a battery provided by the present application is shown; Figure 3 A three-dimensional structural schematic diagram of an embodiment of a battery cover plate 10 of a battery provided in the present application is shown.

[0038] In some embodiments, in combination Figure 1 to Figure 2 As shown, the battery includes: a battery cover 10 , a shell 20 and a plurality of vertical grooves 30 .

[0039] The battery cover 10 includes a substrate 11, which is provided with a flat plate portion 110 and a convex portion 111 spaced apart from the edge of the flat plate portion 110 along a first direction; the housing 20 can be buckled with the battery cover 10, wherein when the housing 20 and the battery cover 10 are buckled, the inner wall of the housing 20 is in contact with the outer edge of the convex portion 111. A plurality of vertical grooves 30 are spaced apart along the circumferential direction at the outer edge of the convex portion 111.

[0040] In the present application embodiment, combined Figure 2 and Figure 3 As shown, by arranging a plurality of vertical grooves 30 on the outer edge of the protrusion 111 of the battery cover plate 10, during the welding process of the battery cover plate 10 and the shell 20, the solder used for welding can penetrate deeper into the shell 20 along the vertical grooves 30, that is, the metal molten pool is deeper during the welding process, thereby effectively enhancing the welding strength between the battery cover plate 10 and the shell 20.

[0041] Among them, providing a plurality of vertical grooves 30 can also effectively increase the weld area, allowing more liquid metal to penetrate into the weld, making the molten weld pool fuller, thereby effectively making the battery weld easier to meet the requirements of side laser welding and improving the efficiency of side laser welding.

[0042] In addition, compared with the current method of adjusting the welding process and changing the power of the welding equipment, providing vertical grooves 30 at the fitting portion between the protrusion 111 of the battery cover 10 and the shell 20 can effectively enhance the welding effect and reduce the production cost of the battery.

[0043] Exemplarily, the battery cover 10 includes a positive electrode cover 12 and a negative electrode cover 13, and the negative electrode cover 13 and the positive electrode cover 12 are respectively buckled on both sides of the housing 20 along the first direction. However, the present application does not limit the battery cover 10, for example, the housing 20 has only one side opening, and the positive and negative electrodes of the battery are arranged on the battery cover 10 at the same time.

[0044] In some embodiments, in combination Figure 1 As shown, when the battery cover 10 is buckled with the housing 20, the flat plate portion 110 of the battery cover 10 protrudes out of the housing 20 by 0.1 mm to 0.5 mm along the first direction.

[0045] In the embodiment of the present application, the flat plate portion 110 of the battery cover plate 10 is thickened so that the flat plate portion 110 of the welded battery cover plate 10 protrudes from the shell 20 by 0.1mm to 0.5mm, for example, 0.3mm. For example, the flat plate portion 110 of the battery cover plate 10 can be widened so that when the battery cover plate 10 and the shell 20 are buckled, it can protrude from the outer edge of the shell 20 by a set width, thereby effectively avoiding the deformation of the battery cover plate 10 caused by the heat source area with highly concentrated energy during the welding process.

[0046] The cooperation between the flat plate portion 110 of the battery cover 10 and the vertical grooves 30 can effectively allow more liquid metal to penetrate, and further avoid problems such as welding explosion caused by the laser being refracted into the shell 20.

[0047] See also Figure 4 As shown, Figure 4 for Figure 3 A magnified view of the local structure of part A.

[0048] In some embodiments, the protrusion 111 of the battery cover 10 includes a first step 112 and a second step 113, the outer edge of the first step 112 is bent and connected to the outer edge of the second step 113, and the first step 112 is away from the flat plate portion 110 along a first direction; wherein the vertical groove 30 passes through the second step 113 along the first step 112 to the flat plate portion 110.

[0049] In the embodiment of the present application, the first step 112 and the second step 113 are bent and connected, that is, the connection between the first step 112 and the second step 113 is set as a bevel, so that when the convex portion 111 of the battery cover 10 is buckled into the shell 20, it can be more easily pressed into the shell 20 and firmly connected with the shell 20. Among them, the vertical groove 30 extends along the bevel to the flat plate portion 110, which is also more convenient for the infiltration of liquid metal during the welding process.

[0050] See also Figures 5 and 6 As shown, Figure 5 A schematic structural diagram of an embodiment of a V-shaped vertical groove 30 of a battery provided by the present application is shown; Figure 6 A schematic structural diagram of an embodiment of a teardrop-shaped vertical groove 30 of a battery provided by the present application is shown.

[0051] In some embodiments, the projection shape of the vertical groove 30 along the first direction is V-shaped or teardrop-shaped.

[0052] In the embodiment of the present application, the shape of the vertical groove 30 can be a V-shaped groove or a water drop-shaped groove, wherein, in combination with Figure 5 As shown, when the vertical groove 30 is V-shaped, the liquid metal in the V-shaped groove has a larger contact area with the inside of the shell 20 (ie, a larger weld). The depth of the vertical groove 30 located at the second step 113 along the second direction is 0.1 mm to 0.3 mm, that is, Figure 5 The length of the line segment a shown is 0.1 mm to 0.3 mm. For example, when the vertical groove 30 is V-shaped, the groove depth is 0.2 mm, and the tool radius R0.1 is applicable.

[0053] Combination Figure 6 As shown, the liquid metal in the water drop-shaped groove is more located inside the shell 20, and the fitting area between the water drop-shaped groove and the inside of the shell 20 is smaller than that of the V-shaped groove (i.e., the weld is smaller). By adjusting the shape of the vertical groove 30, the area of ​​the weld can be effectively controlled. For example, when the vertical groove 30 is a water drop shape, the depth of the vertical groove 30 located on the second step 113 along the second direction is 0.2 mm to 0.4 mm, i.e. Figure 6 The length of the line segment b shown is 0.2 mm to 0.4 mm. For example, the depth of the teardrop-shaped vertical groove 30 is 0.3 mm, and the width of the groove formed with the second step 113 is 0.2 mm, and the tool radius R0.1 is applicable.

[0054] See also Figure 7 As shown, Figure 7 A top view of an embodiment of a positive electrode cover plate 12 of a battery provided in the present application is shown.

[0055] In some embodiments, a plurality of vertical grooves 30 are located at the outer edge of the protrusion 111 and are arranged at the same interval.

[0056] For example, in combination Figure 7 As shown, two adjacent vertical grooves 30 are arranged at the same distance, for example, the distance between two adjacent vertical grooves 30 is 4 mm.

[0057] In some embodiments, the positive electrode cover plate 12 includes a fixing bracket 120 and a welding copper plate 121 , the fixing bracket 120 is connected to the protrusion 111 of the substrate 11 along the first direction, the welding copper plate 121 is located on the side away from the flat plate portion 110 along the first direction and is fixed to the fixing bracket 120 .

[0058] In some embodiments, when the shell 20 is welded to the battery cover 10, the angle between the shell 20 and the external laser head is 30° to 70°.

[0059] In the embodiment of the present application, when the angle between the laser head and the shell 20 is set to 30° to 70°, the light spot can be effectively elongated so that the weld area covered by the laser is wider, thereby reducing the problem of laser entering the shell 20 and burning the internal battery cells of the shell 20 due to refraction of laser light in the gap.

[0060] The above description is only an implementation method of the present utility model, and does not limit the patent scope of the present utility model. Any equivalent structure or equivalent process transformation made using the contents of the specification and drawings of the present utility model, or directly or indirectly used in other related technical fields, should be included in the protection scope of the present utility model.

Claims

1. A battery, characterized in that: include: A battery cover, the battery cover comprising a substrate, the substrate being provided with a flat plate portion and a convex portion spaced a set distance from an edge of the flat plate portion along a first direction; A shell, the shell being capable of being buckled with the battery cover, wherein when the shell is buckled with the battery cover, the inner wall of the shell is in contact with the outer edge of the protrusion; A plurality of vertical grooves are arranged at intervals along the circumferential direction on the outer edge of the protrusion.

2. The battery according to claim 1, characterized in that When the battery cover is buckled with the shell, the flat plate portion of the battery cover protrudes from the shell by 0.1 mm to 0.5 mm along the first direction.

3. The battery according to claim 1, characterized in that The convex portion of the battery cover plate includes a first step and a second step, the outer edge of the first step is bent and connected to the outer edge of the second step, and the first step is away from the flat plate portion along the first direction; wherein the vertical groove runs along the first step through the second step to the flat plate portion.

4. The battery according to claim 1, characterized in that The projection shape of the vertical groove along the first direction is V-shaped or water drop-shaped.

5. The battery according to claim 3 or 4, characterized in that: When the vertical groove is V-shaped, the depth of the vertical groove located on the second step along the second direction is 0.1 mm to 0.3 mm.

6. The battery according to claim 3 or 4, characterized in that: When the vertical groove is a teardrop shape, the depth of the vertical groove located on the second step along the second direction is 0.2 mm to 0.4 mm.

7. The battery according to claim 1, characterized in that The plurality of vertical grooves are arranged at the outer edge of the convex portion at the same interval.

8. The battery according to claim 1, characterized in that When the shell is welded to the battery cover, the angle between the shell and the external laser head is 30° to 70°.

9. The battery according to claim 1, characterized in that The battery cover plate includes a positive cover plate and a negative cover plate, the positive cover plate includes a fixing bracket and a welding copper plate, the fixing bracket is connected to the protrusion of the substrate along the first direction, the welding copper plate is located on the side away from the flat plate portion along the first direction and is fixed to the fixing bracket; the negative cover plate and the positive cover plate are respectively buckled on both sides of the shell along the first direction.

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