Battery and electronic device

Abstract

The utility model provides a battery and an electronic device, and relates to the technical field of batteries. The cover plate seals the opening, the part, close to the edge, of the cover plate protrudes towards the inner cavity of the shell to form a boss, the side, back on to the inner cavity of the shell, of the boss comprises a groove, the part, located on the radial outer side of the boss, of the cover plate forms a connecting edge, the boss is embedded into the opening, and the connecting edge is in lap joint with the end of the shell. A welding mark formed by welding is arranged between the connecting edge and the end part of the shell, and the sectional dimension of the welding mark is gradually reduced in the direction from the radial outer side to the radial inner side of the cover plate; the inner wall of the groove comprises a bottom wall and an outer groove wall surrounding the periphery of the bottom wall, and a stamping groove formed through stamping is formed in the connecting position of the bottom wall and the outer groove wall. According to the battery disclosed by the utility model, when the shell of the battery is sealed and welded, laser can be prevented from irradiating the electrode assembly, so that the electrode assembly is prevented from being damaged, and the product yield is ensured.

Description

Technical Field

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

[0002] With the development of social economy, more and more electrical equipment uses batteries as energy storage and supply devices, such as new energy vehicles, communication base stations, energy storage containers, etc.

[0003] At present, when some models of batteries are sealed by laser welding, there is a certain gap between the side wall and the outer shell due to the boss formed by stamping the edge of the cover. This makes it easy for the incident laser to reflect in the gap and reach the electrode assembly inside the outer shell, causing damage to the electrode assembly and leading to product quality problems. Utility Model Content

[0004] In view of the above problems, the utility model provides a battery and an electronic device, which can prevent laser irradiation to the electrode assembly when sealing and welding the battery shell, thereby avoiding damage to the electrode assembly and ensuring product yield.

[0005] The utility model provides a battery, comprising: a shell, comprising an opening; a cover plate, closing the opening, a portion of the cover plate adjacent to an edge protruding toward an inner cavity of the shell to form a boss, the boss comprising a groove on a side facing away from the inner cavity of the shell, a portion of the cover plate located radially outside the boss constituting a connecting edge, the boss being embedded in the opening, the connecting edge overlapping the end of the shell, and a weld mark formed by welding between the connecting edge and the end of the shell, the cross-sectional size of the weld mark gradually decreasing in a direction from the radial outer side of the cover plate toward the radial inner side, the cross-sectional size being determined by the central axis of the cover plate and any one radial line; the inner wall of the groove comprising a bottom wall and an outer groove wall surrounding the outer periphery of the bottom wall, a stamping groove formed by stamping being provided at the connection between the bottom wall and the outer groove wall.

[0006] In some embodiments, the outer groove wall includes a straight wall portion extending along the thickness direction of the cover plate, and in the radial direction of the cover plate, the outermost end of the stamping groove does not exceed the straight wall portion.

[0007] In some embodiments, the stamping groove has a groove cross section taken along a reference plane, wherein the reference plane is determined by the central axis of the cover plate and any radial line, and the groove cross section is a symmetrical structure on either side of the central axis along the radial direction of the cover plate.

[0008] In some embodiments, the stamping groove has a groove cross-section taken along a reference surface, wherein the reference surface is determined by the central axis of the cover plate and any radial line, and the groove cross-section is an asymmetric structure on any side of the central axis along the radial direction of the cover plate, and the deepest part of the stamping groove is located on the side of the center line L of the groove cross-section of the stamping groove in its own width direction close to the outer groove wall.

[0009] In some embodiments, the height H1 of the cover plate at the boss is in the range of 0.8mm≤H1≤5mm; and / or the depth H2 of the groove in the thickness direction of the cover plate is in the range of 0.1mm≤H2≤4.5mm; and / or the depth H3 of the stamping groove in the thickness direction of the cover plate is in the range of 0.05mm≤H3≤0.4mm; and / or the outer side surface of the boss includes a straight extension portion that is in contact with the inner wall of the outer shell, and the height H4 of the straight extension portion in the thickness direction of the cover plate is in the range of H4≥0.1mm; and / or, in the radial direction of the cover plate, the width W1 of the stamping groove and the width W2 of the groove satisfy the following relationship: 0.05≤W1 / W2≤0.2; and / or, an outer chamfer is also provided at the connection between the outer side surface and the bottom surface of the boss, and the radius R1 of the outer chamfer is in the range of 0.1mm≤R1≤1.2mm.

[0010] In some embodiments, the battery further includes: an electrode assembly, the electrode assembly being disposed in the outer shell, and a pole ear being provided at one end of the electrode assembly facing the cover plate; a portion of the bottom wall other than the stamping groove is provided with a welding area, and the cover plate is electrically connected to the pole ear through the welding area.

[0011] In some embodiments, the battery further includes: a current collecting plate, the current collecting plate is disposed between the cover plate and the pole lug, the current collecting plate is welded to the welding area of ​​the cover plate and the pole lug respectively, and the boss abuts against the current collecting plate.

[0012] In some embodiments, along the radial direction of the cover plate, a minimum spacing T between the stamping groove and the welding area satisfies: 0.2 mm ≤ T ≤ 1 mm.

[0013] In some embodiments, the hardness of the cover plate is greater than or equal to 100 HV.

[0014] A second aspect of the present invention provides an electronic device, comprising: the battery described in the first aspect of the present invention.

[0015] According to the battery of the utility model, a boss is arranged at the edge of the cover plate so that the boss can be embedded in the opening of the shell, the boss is provided with a connecting edge overlapped and welded with the end face of the shell along the radial outer side, the boss is provided with a groove on the side facing away from the electrode assembly, and a stamping groove formed by stamping is provided in the groove. During the forming process of the stamping groove, the pressure generated by the stamping will squeeze the metal at the connection between the bottom wall of the groove and the outer groove wall to flow to the outer side of the boss, so that the chamfer of the boss facing the inner wall of the shell can be reduced, the straight extension part of the outer side of the boss is lengthened, the outer side of the boss and the inner wall of the shell are better fitted, and the boss can better block the laser. In this way, when the gap between the connecting edge and the end face of the shell is welded by laser welding equipment, after the laser enters the inner side of the shell, the laser can be prevented from being reflected in the gap between the outer side of the boss and the inner wall of the shell, thereby preventing the laser from being irradiated to the electrode assembly and causing damage to the electrode assembly, which can improve the welding quality of the battery and ensure the product yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 It is a schematic diagram of the structure of batteries in some embodiments of the utility model;

[0018] Figure 2 For along Figure 1 Sectional view of the middle groove section AA;

[0019] Figure 3 for Figure 2 The middle circle shows an enlarged view of site B;

[0020] Figure 4 A schematic diagram of cover plate material flow during the stamping groove forming process of some embodiments of the utility model;

[0021] Figure 5 Schematic diagram of cover plate material flow during the stamping groove forming process of other embodiments of the utility model;

[0022] Figure 6 It is a partial structural schematic diagram of a battery in some embodiments of the utility model;

[0023] Figure 7 Schematic diagram of the structure of electrode assemblies of some embodiments of the present invention.

[0024] Description of reference numerals:

[0025] 100-battery;

[0026] 1-housing; 11-side wall; 12-top wall;

[0027] 2-cover plate; 21-boss; 210-outer side surface; 211-outer chamfer; 212-straight extension portion; 213-bottom surface; 22-groove; 221-inner chamfer; 222-bottom wall; 223-outer groove wall; 2231-straight wall portion; 224-welding area; 23-stamping groove; 24-connecting edge; 25-welding stamp;

[0028] 3-electrode assembly; 31-ear; 32-positive electrode sheet; 321-positive electrode current collector; 322-positive electrode active coating; 323-positive electrode ear; 33-negative electrode sheet; 331-negative electrode current collector; 332-negative electrode active coating; 34-diaphragm;

[0029] 4-current collecting plate; 5-positive current collecting plate; 6-pole; L-center line. DETAILED DESCRIPTION

[0030] In order to make the above-mentioned purposes, features and advantages of the embodiments of the present application more obvious and understandable, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work belong to the scope of protection of this application.

[0031] With the development of social economy, more and more electrical equipment uses batteries as energy storage and supply devices, such as new energy vehicles, communication base stations, energy storage containers, etc. At present, some models of batteries will use stamping technology to set a boss on the edge of the cover plate, the boss is embedded in the shell, and then the shell is sealed by laser welding. However, for steel shell batteries or other batteries with higher shell strength, the cover plate is difficult to form during stamping due to its high strength, which easily makes the chamfer of the side wall used to match the shell on the stamped boss larger. The larger chamfer will cause the straight line part on the side wall of the boss to be shorter or even no straight line part, and there will be a certain gap between the side wall of the boss and the shell. In this way, when welding the matching gap between the cover plate and the shell, the incident laser is easily reflected in the gap and reaches the electrode assembly inside the shell, causing damage to the electrode assembly and leading to product quality problems.

[0032] In view of this, the present embodiment provides a battery 100, which can be a primary battery or a secondary battery. A primary battery refers to a battery that cannot be recharged and reused after the battery is discharged, and a secondary battery refers to a battery that can be recharged to activate the active material and continue to be used after the battery is discharged. The battery can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel cadmium battery, etc., and the present embodiment of the application does not limit this.

[0033] Combination Figure 1-Figure 2 Specifically, the battery 100 of this embodiment may include: a housing 1, a cover plate 2, and an electrode assembly 3. The housing 1 has an opening at one end, and the inner cavity of the housing 1 serves as a receiving cavity for the electrode assembly 3. Taking the battery 100 as a cylindrical battery as an example, the housing 1 may be cylindrical with an opening at the top or bottom, and the inner side of the housing 1 defines a cylindrical receiving cavity. The cover plate 2 may be disposed on the opening of the housing 1 to close the opening.

[0034] refer to Figure 3 The electrode assembly 3 is arranged in the inner cavity of the shell 1, and a pole ear 31 is provided at one end of the electrode assembly 3 facing the cover plate 2, and the pole ear 31 is electrically connected to the cover plate 2. For example, the cover plate 2 can be a negative cover plate, and the pole ear 31 can be a negative pole ear. The negative cover plate and the negative pole ear can be directly welded to achieve electrical connection, or the negative cover plate and the negative pole ear are electrically connected through an intermediate adapter such as a current collecting plate 4. At this time, the negative cover plate 2 and the negative pole ear are both welded to the current collecting plate 4.

[0035] Combination Figure 2 The housing 1 further includes a side wall 11 and a top wall 12. The side wall 11 is arranged around the top wall 12. The top wall 12 is located at the end of the side wall 11 opposite to the opening. The battery 100 is also provided with a positive current collector 5 and a pole 6. The pole 6 is arranged through the top wall. A positive pole ear 323 is provided at one end of the electrode assembly 3 facing the pole 6. The positive current collector 5 is arranged between the pole 6 and the electrode assembly 3. The positive current collector 5 is welded to the pole 6 and the positive pole ear 323 of the electrode assembly 3 respectively. At this time, the above-mentioned current collector 4 can be used as the negative current collector of the battery 100, and the pole ear 31 at one end of the electrode assembly 3 facing the cover plate 2 is used as the negative pole ear of the electrode assembly 3.

[0036] Optionally, refer to Figure 7 The electrode assembly 3 may include a positive electrode sheet 32, a negative electrode sheet 33 and a separator 34, wherein the positive electrode sheet 32 ​​includes a positive electrode current collector 321 and a positive electrode active coating 322 coated on the surface of the positive electrode current collector 321, and the negative electrode sheet 33 includes a negative electrode current collector 331 and a negative electrode active coating 332 coated on the surface of the negative electrode current collector 331. Taking the battery 100 as a cylindrical battery 100 as an example, the positive electrode sheet 32, the separator 34 and the negative electrode sheet 33 are sequentially stacked and wound to form a wound electrode assembly 3.

[0037] Of course, in other possible embodiments, the battery 100 can be a square shell battery. In this case, the positive electrode sheet 32, the separator 34 and the negative electrode sheet 33 can be stacked in sequence and then wound to form a wound electrode assembly 3; or, the positive electrode sheet 32, the separator 34 and the negative electrode sheet 33 are all multi-layered, the positive electrode sheet 32 ​​and the negative electrode sheet 33 are alternately stacked, and the positive electrode sheet 32 ​​and the negative electrode sheet 33 are separated by the separator 34 to form a stacked electrode assembly 3.

[0038] refer to Figure 3 , the portion of the cover plate 2 adjacent to the edge protrudes toward the inner cavity of the shell 1 to form a boss 21, and the side of the boss 21 facing away from the inner cavity of the shell 1 includes a groove 22. For example, the boss 21 can be formed by stamping the edge of the cover plate 2. During stamping, the boss 21 is formed on the inner surface of the cover plate 2 (i.e., the side surface facing the accommodating cavity), and the groove 22 is formed on the side of the boss 21 facing away from the accommodating cavity (i.e., the outer surface of the cover plate 2). In addition, the portion of the cover plate 2 radially outside the boss 21 is formed as a connecting edge 24. When the boss 21 is embedded in the opening, the connecting edge 24 overlaps the end of the shell 1, and the connecting edge 24 is welded to the end face of the shell 1, for example, by laser welding, ultrasonic welding, etc. At this time, a weld mark 25 is formed between the connecting edge 24 and the end face of the shell 1. In the direction from the radial outer side to the radial inner side of the cover plate 2, the cross-sectional size of the weld mark 25 gradually decreases. The cross-sectional size here can be determined by the central axis of the cover plate 2 and any radial line, for example Figure 1 and Figure 2 AA section shown in .

[0039] Combination Figure 3 It should be noted that in this embodiment, the laser welding equipment can perform laser seam welding from the side of the shell 1 along the radial direction of the cover plate 2 toward the gap between the connecting edge 24 and the end face of the shell 1 (such as Figure 3 In the embodiment of the present invention, a weld mark 25 is formed between the connecting edge 24 and the outer shell 1, and the cross-sectional dimensions of the weld mark 25 such as the width of the cross section gradually decrease along the direction of the laser transmission and away from the welding equipment. In the present embodiment, a weld mark 25 is formed between the connecting edge 24 and the end face of the outer shell 1, and the cross-sectional dimensions of the weld mark 25 gradually decrease in the direction from the radial outer side of the cover plate 2 toward the radial inner side. By using laser butt welding to weld the matching gap between the connecting edge 24 and the outer shell 1, the gap can be better sealed, and the process is mature and reliable, which can ensure the welding quality.

[0040] refer to Figure 3The inner wall of the groove 22 includes a bottom wall 222 and an outer groove wall 223 surrounding the outer periphery of the bottom wall 222, wherein a stamping groove 23 formed by stamping is provided at the connection between the bottom wall 222 and the outer groove wall 223, that is, the stamping groove 23 is formed on the inner chamfer 221 at the connection between the bottom wall 222 and the outer groove wall 223. Optionally, the stamping groove 23 and the groove 22 can be formed simultaneously in the same stamping process.

[0041] It should be noted that, in the case where the punching groove 23 is not provided, when the cover plate 2 is punched to form the boss 21, the outer chamfer 211 at the intersection of the outer side surface 210 (opposite to the outer groove wall 223 of the groove 22) and the bottom surface (opposite to the bottom wall 222 of the groove 22) of the boss 21 is relatively large, so that the straight extension portion 212 of the outer surface of the boss 21 (the straight extension portion 212 is the portion where the outer side surface 210 of the boss 21 fits the shell 1, and the portion extends along the axial direction of the cover plate 2) is relatively short, and there is a certain gap between the outer side surface 210 of the boss 21 and the inner wall of the shell 1. In this way, when the connecting edge 24 and the end face of the shell 1 are welded to form the weld mark 25, the laser emitted by the laser welding device toward the gap between the connecting edge 24 and the end face of the shell 1 is easily reflected in the gap between the outer side surface 210 of the boss 21 and the inner wall of the shell 1 after entering the accommodating cavity, and finally reflected on the electrode assembly 3, causing damage to the electrode assembly 3. In this embodiment, a stamping groove 23 is provided at the connection between the bottom wall 222 and the outer groove wall 223 of the groove 22. During the forming process of the stamping groove 23, the stamping equipment squeezes the inner wall of the groove 22, so that the material at the connection between the bottom wall 222 and the outer groove wall 223 flows and deforms toward the side of the shell 1, so that the outer chamfer 211 of the boss 21 becomes smaller, and the straight extension portion 212 of the outer side surface 210 of the boss 21 is lengthened, so that the outer side surface 210 of the boss 21 fits better with the inner wall of the shell 1. In this way, even if the laser enters the inner side of the shell 1 from the gap between the connecting edge 24 and the end face of the shell 1, the boss 21 can block the laser to prevent the laser from being reflected to the electrode assembly 3 and causing damage to the electrode assembly 3.

[0042] According to the battery 100 of the embodiment of the utility model, a boss 21 is provided at the edge of the cover plate 2 so that the boss 21 can be embedded in the opening of the shell 1. The boss 21 is provided with a connecting edge 24 that overlaps and welds with the end face of the shell 1 along the radial outer side. The boss 21 is provided with a groove 22 on the side facing away from the electrode assembly 3. The connection between the bottom wall 222 of the groove 22 and the outer groove wall 223 is provided with a stamping groove 23 formed by stamping. During the forming process of the stamping groove 23, the pressure generated by the stamping equipment will squeeze the metal at the connection between the bottom wall 222 of the groove 22 and the outer groove wall 223 to flow toward the outer side of the boss, so that the chamfer of the boss 21 facing the inner wall of the shell 1 becomes smaller, the straight extension part 212 of the outer side surface 210 of the boss 21 is lengthened, and the outer side surface 210 of the boss 21 has a better fit with the inner wall of the shell 1, so that the boss 21 can better block the laser. In this way, when using laser welding equipment to weld the gap between the connecting edge 24 and the end face of the outer shell 1, after the laser enters the inner side of the outer shell 1, the laser can be prevented from being reflected in the gap between the outer side surface 210 of the boss 21 and the inner wall of the outer shell 1, thereby preventing the laser from irradiating the electrode assembly 3 and causing damage to the electrode assembly 3, which can improve the welding quality of the battery 100 and ensure the product yield.

[0043] In some embodiments, reference Figure 3 and Figure 4 The opening direction of the punching groove 23 is along the axial direction of the cover plate 2 and away from the inner cavity of the shell 1. The outer groove wall 223 of the groove 22 includes a straight wall portion 2231 extending along the thickness direction of the cover plate 2. The straight wall portion 2231 is opposite to and parallel to the straight extension portion 212 of the outer side surface 210 of the boss 21. In the radial direction of the cover plate 2, the outermost end of the punching groove 23 does not exceed the straight wall portion 2231. In this way, it is only necessary to set a protruding structure adapted to the punching groove 23 on the punching equipment, and the punching equipment can be used to form the groove 22 and the punching groove 23 simultaneously, that is, when punching along the thickness direction of the cover plate 2, the protruding structure on the punching equipment and the outer groove wall 223 of the groove 22 do not interfere with each other in the thickness direction of the cover plate 2. After the punching groove 23 is processed, the punching equipment is more likely to withdraw from the groove 22.

[0044] In addition, the opening direction of the groove 22 is roughly the same as the opening direction of the stamping groove 23, so that the stamping equipment only needs to perform one stamping along the thickness direction of the cover plate 2 to form the stamping groove 23 and the groove 22, making the manufacturing process of the cover plate 2 simpler and more efficient; of course, it is understandable that two stamping steps can also be used, that is, first stamping out the groove 22 and then stamping out the stamping groove 23.

[0045] The punching groove 23 has a Figure 1 and Figure 2The reference plane can be determined by the central axis and any radial line of the cover plate 2. In other words, the reference plane passes through the central axis and the radial line of the cover plate 2. Since the punching groove 23 is a ring around the cover plate 2, the groove cross section of the punching groove 23 at the reference plane includes two parts, which are respectively located on both sides of the central axis of the cover plate 2.

[0046] Reference Figure 3 In this embodiment, the groove cross section on either side of the central axis along the radial direction of the cover plate 2 is a symmetrical structure. For example, the groove cross section of the punching groove 23 on either side of the radial direction of the central axis of the cover plate 2 can be formed into a V-shaped, U-shaped or other symmetrical structure, so that during the punching process, the cover plate material corresponding to the punching groove 23 can flow evenly toward the circumference to reduce the outer chamfer of the boss 21 and increase the length of the straight extension portion 212 on the outer side surface 210 of the boss 21.

[0047] In other embodiments, reference Figure 4 , the portion of the groove cross section on any side of the central axis along the radial direction of the cover plate 2 can be an asymmetric structure, and the deepest part of the stamping groove 23 is located on the side of the center line L of the groove cross section in its width direction close to the outer groove wall 223, where the width direction of the stamping groove 23 is parallel to the radial direction of the cover plate 2. In this way, compared with the solution in which the stamping groove 23 is a symmetrical structure, when processing the stamping groove 23, this embodiment can make the cover plate 2 material between the inner chamfer 221 and the outer chamfer 211 flow and deform mainly toward one side of the shell 1, reducing the flow deformation of the material in other directions, so as to more efficiently reduce the outer chamfer 211 of the boss 21, increase the length of the straight extension part 212 on the outer side surface 210 of the boss 21, which can not only improve the forming efficiency of the stamping groove 23, but also ensure the tightness of the fit between the boss 21 and the shell 1.

[0048] In some embodiments, in combination Figure 6, the range of the height H1 of the cover plate 2 at the boss 21 is: 0.8mm≤H1≤5mm, where the height H1 of the cover plate 2 at the boss 21 is the sum of the height of the boss 21 and the thickness of the non-boss part of the cover plate 2. For example, the value of the height H1 of the cover plate 2 at the boss 21 can be 0.8mm, 1mm, 1.5mm, 2mm, 2.5mm, 3.5mm, 4mm, 4.5mm or 5mm. Of course, the utility model does not limit this. The height H1 of the cover plate 2 at the boss 21 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it is avoided that the height of the boss 21 is too small, for example, when it is less than 0.8mm, the depth of the boss 21 embedded in the shell 1 is too small, the boss 21 cannot effectively block the laser, and the cover plate 2 cannot form a stable match with the shell 1. On the other hand, it is avoided that the height of the boss 21 is too large, for example, when it is greater than 5mm, the boss 21 occupies too much internal space of the shell 1, which is not conducive to improving the internal space utilization rate and energy density of the battery 100.

[0049] In some embodiments, in combination Figure 6 , the depth H2 of the groove 22 in the thickness direction of the cover plate 2 has a value range of: 0.1mm≤H2≤4.5mm. For example, the depth H2 of the groove 22 in the thickness direction of the cover plate 2 can be 0.1mm, 0.2mm, 0.5mm, 0.8mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm or 4.5mm. Of course, the present invention does not limit this. The depth H2 of the groove 22 in the thickness direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it is avoided that when the depth of the groove 22 is too small, for example, less than 0.1mm, the height of the boss 21 is too small, the boss 21 cannot effectively block the laser, and form a stable fit with the shell 1. On the other hand, it is avoided that when the depth of the groove 22 is too large, for example, greater than 4.5mm, the boss 21 occupies too much internal space of the shell 1, which is not conducive to improving the internal space utilization and energy density of the battery 100. It can be understood that the depth of the groove 22 is always smaller than the thickness of the cover plate 2 at the boss 21 .

[0050] In some embodiments, in combination Figure 6The depth H3 of the stamping groove 23 in the thickness direction of the cover plate 2 is in the range of 0.05mm≤H3≤0.4mm. For example, the depth H3 of the stamping groove 23 in the thickness direction of the cover plate 2 can be 0.05mm, 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm or 0.4mm. Of course, the utility model is not limited to this. The depth H3 of the stamping groove 23 in the thickness direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, when the depth of the punching groove 23 is too small, for example, less than 0.05mm, the material of the cover plate 2 between the inner chamfer 221 and the outer chamfer 211 is squeezed too little during the forming process of the punching groove 23, the outer chamfer 211 of the boss 21 is not effectively reduced, and the outer side surface 210 of the boss 21 cannot form an effective fit with the inner wall of the shell 1, so that the laser blocking effect of the boss 21 is limited. On the other hand, when the depth of the punching groove 23 is too large, for example, greater than 0.4mm, the bottom wall 222 of the groove 22 is pressed through, causing the cover plate 2 to be damaged and scrapped. It can be understood that the depth of the punching groove 23 is always less than the wall thickness of the boss 21.

[0051] In some embodiments, in combination Figure 6 The outer side surface 210 of the boss 21 includes a straight extension portion 212. For example, the portion of the outer side surface 210 of the boss 21 other than the chamfer is formed as a straight extension portion 212. The height H4 of the straight extension portion 212 in the thickness direction of the cover plate 2 has a value range of: 0.1mm≤H4≤2mm. For example, the height H4 of the straight extension portion 212 in the thickness direction of the cover plate 2 can be 0.1mm, 0.2mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm or 2mm. Of course, the utility model does not limit this. The height H4 of the straight extension portion 212 in the thickness direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it is possible to avoid the height of the straight extension portion 212 being too small, for example, when it is less than 0.1 mm, the depth of the boss 21 embedded in the outer shell 1 is too small, which is not conducive to better shielding the laser at the weld mark 25 between the connecting edge 24 and the end face of the outer shell 1. On the other hand, it is possible to avoid the height of the straight extension portion 212 being too large, for example, greater than 2 mm, which causes the boss 21 to occupy too much internal space of the outer shell 1, which is not conducive to improving the internal space utilization and energy density of the battery 100.

[0052] In some embodiments, in combination Figure 6, along the radial direction of the cover plate 2, the width W1 of the punching groove 23 and the width W2 of the groove 22 satisfy: 0.1≤W1 / W2≤1. For example, the ratio of W1 to W2 can be 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 1. When the ratio is 1, the width W1 of the punching groove 23 in the radial direction of the cover plate 2 is the same as the width W2 of the groove 22. Of course, the utility model does not limit this, and the ratio of W1 to W2 can be reasonably selected within the above range according to actual needs. In this way, it can be ensured that the processing equipment can smoothly extend into the groove 22 to process the stamping groove 23, and it can be ensured that when processing the stamping groove 23, the cover plate material at the stamping groove 23 can be pushed to better flow toward the outer groove wall 223 of the groove 22, so as to reduce the outer chamfer 211 of the boss 21 and increase the length of the straight extension portion 212 on the outer side surface 210 of the boss 21. In this way, when laser butt welding is performed between the connecting edge 24 of the cover plate 2 and the end of the shell 1, the boss 21 can better block the laser.

[0053] In some embodiments, in combination Figure 6 , an outer chamfer 211 is also provided at the connection between the outer side surface 210 and the bottom surface 213 of the boss 21. The outer chamfer 211 is opposite to the inner chamfer 221. The radius R1 of the outer chamfer 211 has a value range of: 0.1mm≤R1≤1.2mm. For example, the radius R1 of the outer chamfer 211 can be 0.1mm, 1.2mm, 0.4mm, 0.5mm, 0.8mm, 1mm, 1.2mm. Of course, the utility model does not limit this. The radius R1 of the outer chamfer 211 can be reasonably selected within the above range according to actual needs. That is to say, after the stamping groove 23 is processed, the radius of the outer chamfer 211 of the boss 21 facing the side of the shell 1 is within the above range, which can ensure that the outer side surface 210 of the boss 21 fits well with the inner wall of the shell 1 to block the laser.

[0054] In some embodiments, the bottom wall 222 of the groove 22 is provided with a welding area 224 except for the stamping groove 23. The welding area 224 is a welding trace formed by welding the cover plate 2 and the internal components of the battery; the cover plate 2 can be electrically connected to the pole lug 31 through the welding area 224. For example, the welding area 224 and the pole lug 31 can be directly welded to achieve electrical connection between the cover plate 2 and the pole lug 31. Alternatively, the welding area 224 can also be electrically connected to the pole lug 31 through an intermediate adapter such as a current collecting plate 4. In this way, the connection method between the cover plate 2 and the pole lug 31 is diverse and can be reasonably selected according to actual needs.

[0055] In a specific example, the battery 100 may further include: a current collecting plate 4. The current collecting plate 4 is disposed between the cover plate 2 and the pole lug 31, and the current collecting plate 4 is welded to the welding area 224 of the cover plate 2 and the pole lug 31 respectively. In other words, the cover plate 2 and the pole lug 31 are transitionally connected through the current collecting plate 4, and the current collecting plate 4 serves as an intermediate adapter between the cover plate 2 and the pole lug 31. At this time, the boss 21 can be in contact with the collecting disk 4. In this way, on the one hand, the boss 21 can be used to press the collecting disk 4, thereby ensuring that the positions of the collecting disk 4 and the electrode assembly 3 in the outer shell 1 are fixed. On the other hand, since the boss 21 is a part of the structure of the cover plate 2 and is a metal part, even if the boss 21 is not electrically connected to the collecting disk 4 (such as the middle area of ​​the collecting disk 4 is welded to the cover plate 2, and the boss 21 and the welding area 224 are radially spaced apart), the boss 21 can be used to conduct heat; and in some possible embodiments, the boss 21 can be directly welded to the collecting disk 4 to achieve conduction between the cover plate 2 and the collecting disk 4. At this time, the boss 21 can achieve both electrical connection and thermal conduction.

[0056] It can be understood that when the bottom wall 222 of the groove 22 and the collector plate 4 are welded by laser penetration welding, the laser irradiation direction is the same as the thickness direction of the cover plate 2. The laser energy density when the laser is irradiated on the surface of the object to be welded is related to the distance from the laser focus to the welding surface. Since the inner wall surface of the stamping groove 23 is not a plane perpendicular to the laser, if welding is performed inside the stamping groove 23, different welding positions have different distances from the laser focus, resulting in different laser energy densities at different points, which may lead to inconsistent welding depths at various points, and it is impossible to ensure that an effective connection is formed between the stamping groove 23 and the collector plate 4. In this embodiment, the welding area 224 is set on the straight part of the bottom wall 222, so that the welding area 224 avoids the stamping groove 23, which can ensure that the laser energy is better focused and penetrates the cover plate 2 to reach the collector plate 4, so that an effective and reliable connection is formed between the boss 21 and the collector plate 4.

[0057] In some embodiments, in combination Figure 6, the width W2 of the groove 22 in the radial direction of the cover plate 2 has a value range of: 2mm≤W2≤15mm. For example, the width W2 of the groove 22 in the radial direction of the cover plate 2 can be 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm or 15mm. Of course, the utility model does not limit this, and the width W2 of the groove 22 in the radial direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it can be avoided that the width of the groove 22 is too small, for example, when it is less than 2mm, it is difficult for the welding equipment to extend into the groove 22 for welding operations, and it is difficult for the processing equipment to extend into the groove 22 to process the stamping groove 23; on the other hand, it can be avoided that the width of the groove 22 is too large, for example, when it is greater than 15mm, the area of ​​the surface of the cover plate 2 used for thermal contact with the module heat dissipation system is too small, which is not conducive to the external heat dissipation of the battery 100.

[0058] In some embodiments, in combination Figure 3 and Figure 6 , the width W3 of the welding area 224 in the radial direction of the cover plate 2 has a value range of: 0.5mm≤W3≤13mm. For example, the width W3 of the welding area 224 in the radial direction of the cover plate 2 can be 0.5mm, 1mm, 2mm, 4mm, 6mm, 8mm, 10mm, 12mm or 13mm. Of course, the utility model does not limit this. The width W3 of the welding area 224 in the radial direction of the cover plate 2 can be reasonably selected within the above range according to actual needs. In this way, on the one hand, it can be avoided that the width of the welding area 224 is too small. For example, when it is less than 0.5mm, the welding area between the boss 21 and the collecting plate 4 is too small, resulting in a large resistance at the welding point and poor current carrying capacity. On the other hand, it can be avoided that the width of the welding area 224 is too large. For example, when it is greater than 13mm, the welding area is too large and it is difficult to ensure the welding quality.

[0059] In some embodiments, reference Figure 3 , along the radial direction of the cover plate 2, the minimum spacing T between the stamping groove 23 and the welding area 224 satisfies: 0.2mm≤T≤1mm. For example, the minimum spacing T between the stamping groove 23 and the welding area 224 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm or 1mm. Of course, the utility model does not limit this. The minimum spacing T between the stamping groove 23 and the welding area 224 can be reasonably selected within the above range according to actual needs. In this way, it can avoid the welding energy being transferred to the stamping groove 23 due to too small a spacing, resulting in the phenomenon of welding explosion points. At the same time, it can avoid mutual interference between the stamping groove 23 and the welding area 224, and it is also conducive to releasing stress during the welding process.

[0060] In some embodiments, the hardness of the cover plate 2 is greater than or equal to 100 HV, so that the cover plate 2 can be ensured to have sufficient strength and good pressure resistance. For example, the cover plate 2 can be a steel structure, such as the cover plate 2 can be a general cold-rolled carbon steel sheet and steel strip (SPCC).

[0061] The electronic device according to the second embodiment of the present invention is described below.

[0062] The electronic device of this embodiment can be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, etc. The vehicle can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc.: the spacecraft includes an airplane, a rocket, a space shuttle and a spacecraft, etc.: the electric toy includes a fixed or mobile electric toy, for example, a game console, an electric car toy, an electric ship toy and an electric airplane toy, etc.; the electric tool includes a metal cutting electric tool, a grinding electric tool, an assembly electric tool and an electric tool for railways, for example, an electric drill, an electric grinder, an electric wrench, an electric screwdriver, an electric hammer, an impact drill, a concrete vibrator and an electric planer, etc.; the electronic device can also be a battery module, a battery pack, etc. The embodiment of this application does not impose any special restrictions on the above-mentioned electronic devices.

[0063] The electronic device may include: a device body and the battery 100 in the above embodiment. The device body may include a battery compartment, the battery 100 is disposed in the battery compartment and is electrically connected to the device body, for example, the battery compartment may be provided with a power supply interface, and the battery 100 may be connected to the power supply interface.

[0064] The electronic device of the embodiment of the utility model is provided with the battery 100 in the above embodiment, and the welding quality of the battery 100 is better, which is beneficial to improving the user experience.

[0065] It should be noted that the embodiments represented by "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments", etc. mentioned in the specification may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, such phrases do not necessarily refer to the same embodiment. In addition, when describing specific features, structures or characteristics in conjunction with an embodiment, it is within the knowledge of those skilled in the art to implement such features, structures or characteristics in conjunction with other embodiments that are explicitly or not explicitly described.

[0066] In general, terms should be understood, at least in part, by the context in which they are used. For example, the term "one or more" as used herein may be used to describe any feature, structure, or characteristic in a singular sense, or may be used to describe a combination of features, structures, or characteristics in a plural sense, depending, at least in part, on the context. Similarly, terms such as "a," "an," or "the" may also be understood to convey singular usage or to convey plural usage, depending, at least in part, on the context.

[0067] It should be easily understood that “on,” “above,” and “over” in the present disclosure should be interpreted in the broadest manner, so that “on” not only means “directly on something,” but also includes the meaning of “on something” with intervening features or layers therebetween, and “above” or “over” not only includes the meaning of “above” or “over,” but also may include the meaning of “above” or “over something” with no intervening features or layers therebetween (i.e., directly on something).

[0068] In addition, spatially relative terms, such as "below," "below," "beneath," "above," "above," etc., may be used herein for ease of description to describe the relationship of one element or feature relative to other elements or features as shown in the figures. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. The device may have other orientations (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein may likewise be interpreted accordingly.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A battery, characterized in that: include: a housing, including an opening; A cover plate closes the opening, a portion of the cover plate adjacent to an edge protrudes toward the inner cavity of the shell to form a boss, a side of the boss facing away from the inner cavity of the shell comprises a groove, and a portion of the cover plate located radially outside the boss constitutes a connecting edge, The boss is embedded in the opening, the connecting edge overlaps the end of the shell, and a weld mark formed by welding is provided between the connecting edge and the end of the shell, and the cross-sectional size of the weld mark gradually decreases in the direction from the radial outer side to the radial inner side of the cover plate, and the cross-sectional size is determined by the central axis of the cover plate and any radial line; The inner wall of the groove comprises a bottom wall and an outer groove wall surrounding the outer circumference of the bottom wall, and a stamping groove formed by stamping is provided at the connection between the bottom wall and the outer groove wall.

2. The battery according to claim 1, characterized in that The outer groove wall includes a straight wall portion extending in the thickness direction of the cover plate, In the radial direction of the cover plate, the outermost end of the punched groove does not exceed the straight wall portion.

3. The battery according to claim 2, characterized in that The punching groove has a groove cross section taken along a reference plane, wherein the reference plane is determined by the central axis of the cover plate and any radial line. The groove cross section has a symmetrical structure at a portion on either side of the central axis along the radial direction of the cover plate.

4. The battery according to claim 2, characterized in that The punching groove has a groove cross section taken along a reference plane, wherein the reference plane is determined by the central axis of the cover plate and any radial line. The groove cross section is an asymmetric structure at a portion on either side of the central axis along the radial direction of the cover plate. Furthermore, the deepest part of the punching groove is located on a side of the center line L of the groove cross section of the punching groove in its width direction, close to the outer groove wall.

5. The battery according to claim 1, characterized in that The height H1 of the cover plate at the boss is in the range of: 0.8 mm ≤ H1 ≤ 5 mm; and / or, The depth H2 of the groove in the thickness direction of the cover plate is in the range of: 0.1 mm ≤ H2 ≤ 4.5 mm; and / or, The depth H3 of the punching groove in the thickness direction of the cover plate is in the range of: 0.05 mm ≤ H3 ≤ 0.4 mm; and / or, The outer side surface of the boss includes a straight extension portion that fits the inner wall of the shell, and the height H4 of the straight extension portion in the thickness direction of the cover plate is in the range of: H4 ≥ 0.1 mm; and / or, In the radial direction of the cover plate, the width W1 of the stamping groove and the width W2 of the groove satisfy: 0.05≤W1 / W2≤0.2; and / or, An outer chamfer is also provided at the connection between the outer side surface and the bottom surface of the boss, and the radius R1 of the outer chamfer is in the range of 0.1 mm ≤ R1 ≤ 1.2 mm.

6. The battery according to any one of claims 1 to 5, characterized in that Also includes: An electrode assembly, wherein the electrode assembly is disposed in the housing, and an electrode lug is disposed at one end of the electrode assembly facing the cover plate; A welding area is provided on a portion of the bottom wall except the stamping groove, and the cover plate is electrically connected to the tab via the welding area.

7. The battery according to claim 6, characterized in that Also includes: A current collecting plate is provided between the cover plate and the pole lug, the current collecting plate is welded to the welding area of ​​the cover plate and the pole lug respectively, and the boss abuts against the current collecting plate.

8. The battery according to claim 6, characterized in that Along the radial direction of the cover plate, a minimum spacing T between the stamping groove and the welding area satisfies: 0.2 mm ≤ T ≤ 1 mm.

9. The battery according to any one of claims 1 to 5, characterized in that The hardness of the cover plate is greater than or equal to 100 HV.

10. An electronic device, characterized in that: include: The battery according to any one of claims 1 to 9.

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